Journal articles: 'Parthenogenesis'

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Hoffmann, Ary A., K. Tracy Reynolds, Michael A. Nash, and Andrew R. Weeks. "A high incidence of parthenogenesis in agricultural pests." Proceedings of the Royal Society B: Biological Sciences 275, no. 1650 (July 22, 2008): 2473–81. http://dx.doi.org/10.1098/rspb.2008.0685.

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Parthenogenetic species are assumed to represent evolutionary dead ends, yet parthenogenesis is common in some groups of invertebrates particularly in those found in relatively constant environments. This suggests that parthenogenetic reproduction might be common in pest invertebrates from uniform agricultural environments. Based on the evaluations of two databases from North America and Italy, we found that parthenogenetic species comprised 45 per cent (North America) or 48 per cent (Italy) of pest species derived from genera where parthenogenesis occurred, compared with an overall incidence of 10 per cent or 16 per cent in these genera. In establishing these patterns, we included only genera containing at least some member species that reproduced by parthenogenesis. The high incidence of parthenogenesis in pest species is spread across different families and several insect orders. Parthenogenetic reproduction may be favoured in agricultural environments when particular clones have a high fitness across multiple generations. Increasing the complexity and variability of agricultural environments represents one way of potentially controlling parthenogenetic pest species.

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Wang, Pengcheng, Fangyuan Yang, Zhuo Ma, and Runzhi Zhang. "Chromosome Unipolar Division and Low Expression of Tws May Cause Parthenogenesis of Rice Water Weevil (Lissorhoptrus oryzophilus Kuschel)." Insects 12, no. 4 (March 24, 2021): 278. http://dx.doi.org/10.3390/insects12040278.

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Rice water weevil (RWW) is divided into two types of population, triploid parthenogenesis and diploid bisexual reproduction. In this study, we explored the meiosis of triploid parthenogenesis RWW (Shangzhuang Town, Haidian District, Beijing, China) by marking the chromosomes and microtubules of parthenogenetic RWW oocytes via immunostaining. The immunostaining results show that there is a canonical meiotic spindle formed in the triploid parthenogenetic RWW oocytes, but chromosomes segregate at only one pole, which means that there is a chromosomal unipolar division during the oogenesis of the parthenogenetic RWW. Furthermore, we cloned the conserved sequences of parthenogenetic RWW REC8 and Tws, and designed primers based on the parthenogenetic RWW sequence to detect expression patterns by quantitative PCR (Q-PCR). Q-PCR results indicate that the expression of REC8 and Tws in ovarian tissue of bisexual Drosophila melanogaster is 0.98 and 10,000.00 times parthenogenetic RWW, respectively (p < 0.01). The results show that Tws had low expression in parthenogenetic RWW ovarian tissue, and REC8 was expressed normally. Our study suggests that the chromosomal unipolar division and deletion of Tws may cause parthenogenesis in RWW.

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MATSUDA, MUNEO, and YOSHIKO N. TOBARI. "Genetic analyses of several Drosophila ananassae-complex species show a low-frequency major gene for parthenogenesis that maps to chromosome 2." Genetical Research 83, no. 2 (April 2004): 83–89. http://dx.doi.org/10.1017/s0016672303006657.

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Parthenogenetic strains of several species have been found in the genus Drosophila. The mode of diploidization in the eggs of females has been found to be post-meiotic nuclear fusion. The genetic basis for this parthenogenesis is not understood but is believed to be under the control of a complex polygenic system. We found parthenogenetic females in an isofemale strain (LAE345) of D. pallidosa-like collected in 1981 at Lae, Papua New Guinea, and established a parthenogenetically reproducing strain. Parthenogenetic strains of D. ananassae and D. pallidosa collected at Taputimu, American Samoa had also been established by Futch (1972). D. ananassae, D. pallidosa and D. pallidosa-like are very closely related species belonging to the ananassae complex of the ananassae species subgroup of the melanogaster species group. Using these three species, we found that more than 80% of females from parthenogenetic strains produced progeny parthenogenetically and that inter-specific hybrid females also produced impaternate progeny. In the present report, we demonstrate that the mode of parthenogenesis of D. ananassae appears to be the post-meiotic nuclear doubling of a single meiotic product, and that a major gene responsible for the parthenogenesis maps to the left arm of the second chromosome of D. ananassae. We also suggest that the genetic basis for parthenogenesis capacity may be identical among the three closely related species. We discuss the function of the gene required for parthenogenesis and its significance for the evolutionary process.

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BOHN, HORST, and THOMAS KNEBELSBERGER. "Geographie parthenogenesis in the subaptera-group of Phyllodromica (Blattoptera, Blattellidae, Ectobiinae)." Insect Systematics & Evolution 34, no. 4 (2003): 427–52. http://dx.doi.org/10.1163/187631203x00054.

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AbstractKnebelsberger, T. & Bohn, H.: Geographic parthenogenesis in the subaptera-group of Phyllodromica (Blattoptera, Blattellidae, Ectobiinae). Insect Syst. Evol. 34: 427-452. Copenhagen, December 2003. ISSN 1399-560X. A new case of obligatory thelytokous parthenogenesis in Blattoptera is reported in the Mediterranean species Phyllodromica subaptera (Rambur, 1838) (Blattellidae: Ectobiinae). The females of the parthenogenetic and bisexual forms cannot be distinguished by external features; their distribution was studied by analysis of the sex of the offspring and the contents of spermathecae. The parthenogenetic strain is spread over most of the Mediterranean countries, the bisexual forms are restricted to the Iberian peninsula, a distribution which is in keeping with the term "geographic parthenogenesis".

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Martini, A. C., M. Fiol de Cuneo, R. D. Ruiz, A. A. Ponce, and J. L. Lacuara. "In vitro parthenogenesis of mouse oocytes under several experimental conditions." Zygote 8, no. 1 (February 2000): 45–49. http://dx.doi.org/10.1017/s0967199400000812.

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Although the in vitro fertilisation index is a parameter commonly employed to investigate sperm functional activity, little attention has been given to the occurrence of parthenogenesis. The purpose of this study was to study at 6 h or 22 h incubation: (a) the cleavage-related events that occur in in vitro incubated mouse oocytes, in the absence (parthenogenesis) or presence of homologous spermatozoa; (b) the effect of mineral oil, commonly used in in vitro fertilisation assays; (c) the effect of piroxicam, a prostaglandin synthesis inhibitor, on the parthenogenetic rate; and (d) the influence on parthenogenesis of spontaneous loss of the cumulus oophorus coat during incubation. Under the experimental conditions employed, there was parthenogenetic activation and activation due to fertilisation. Both increased in a time-dependent manner. The mineral oil enhanced the parthenogenetic rate at 22 h incubation. However, it did not have any effect when the oocytes were inseminated. Since we can not discriminate how much of this activation was due to fertilisation and how much to parthenogenesis we must be very careful with this comparison. Piroxicam 10-8 M did not show any effect on the mouse oocyte parthenogenetic rate at neither 6 h or 22 h incubation. Our results suggest that oocyte susceptibility to spontaneous parthenogenetic activation may be modified by the presence of the cumulus and corona radiata cells. In conclusion, we consider that further rigorous studies on these influences are necessary in order to confer more reliability on the results.

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Ramachandran, R., and C. D. McDaniel. "Parthenogenesis in birds: a review." Reproduction 155, no. 6 (June 2018): R245—R257. http://dx.doi.org/10.1530/rep-17-0728.

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Parthenogenesis or ‘virgin birth’ is embryonic development in unfertilized eggs. It is a routine means of reproduction in many invertebrates. However, even though parthenogenesis occurs naturally in even more advanced vertebrates, like birds, it is mostly abortive in nature. In fact, multiple limiting factors, such as delayed and unorganized development as well as unfavorable conditions developing within the unfertilized egg upon incubation, are associated with termination of progressive development of parthenogenetic embryos. In birds, diploid parthenogenesis is automictic and facultative producing only males. However, the mechanisms controlling parthenogenesis in birds are not clearly elucidated. Additionally, it appears from even very recent research that these mechanisms may hinder the normal fertilization process and subsequent embryonic development. For instance, virgin quail and turkey hens exhibiting parthenogenesis have reduced reproductive performance following mating. Also, genetic selection and environmental factors, such as live virus vaccinations, are known to trigger the process of parthenogenesis in birds. Therefore, parthenogenesis has a plausible negative impact on the poultry industry. Hence, a better understanding of parthenogenesis and the mechanisms that control it could benefit commercial poultry production. In this context, the aim of this review is to provide a complete overview of the process of parthenogenesis in birds.

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Osipov, F. A., V. V. Bobrov, N. N. Dergunova, M. S. Arakelyan, and V. G. Petrosyan. "Ecological niches breadth analysis of Darevskia (Lacertidae, Reptilia) parthenogenetic lizards with various scenarios of clonal lineage formation in populations." Current Studies in Herpetology 23, no. 3/4 (December 18, 2023): 108–12. http://dx.doi.org/10.18500/1814-6090-2023-23-3-4-108-112.

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In this work, we tested the conditions for fulfilling the concept of geographic parthenogenesis by a comparative analysis of the breadth of the ecological niches of parental and parthenogenetic lizards of the genus Darevskia with a various number of established hybridization events. Estimates of the breadth of ecological niches of the parthenogenetic species D. rostombekowi Nb = 0.6(±0.08) and parental bisexual species D. raddei raddei – Nb = 0.86(±0.9), D. portschinskii – Nb = 1.21(±0.17) showed that for this parthenogenetic species one of the most important conditions of geographic parthenogenesis is fulfilled, i.e. the niche breadth of the parthenogenetic species is smaller than its parental bisexual species. The niche breadth of another parthenogenetic species D. dahli Nb = 0.86(±0.12) is smaller than that of the «paternal» species D. portschinskii – Nb = 1.21(±0.17), but larger than that of the «maternal» species D. mixta Nb = 0.48 (±0.08), which only partially agrees with the condition of geographic parthenogenesis. This mismatch is due to the fact that D. dahli was formed as a result of several independent hybridization events, which resulted in the formation of multiple clonal lines derived from different parental pairs of D. portschinskii and D. mixta.

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HALES, DINAH F., ALEX C. C. WILSON, MATHEW A. SLOANE, JEAN-CHRISTOPHE SIMON, JEAN-FRANÇOIS LEGALLIC, and PAUL SUNNUCKS. "Lack of detectable genetic recombination on the X chromosome during the parthenogenetic production of female and male aphids." Genetical Research 79, no. 3 (June 2002): 203–9. http://dx.doi.org/10.1017/s0016672302005657.

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We used polymorphic microsatellite markers to look for recombination during parthenogenetic oogenesis between the X chromosomes of aphids of the tribe Macrosiphini. We examined the X chromosome because it comprises ∼25% of the genome and previous cytological observations of chromosome pairing and nucleolar organizer (NOR) heteromorphism suggest recombination, although the same is not true for autosomes. A total of 564 parthenogenetic females of Myzus clones with three distinct reproductive modes (cyclical parthenogenesis, obligate parthenogenesis and obligate parthenogenesis with male production) were genotyped at three informative X-linked loci. Also, parthenogenetically produced males from clones encompassing the full range of male-producing reproductive strategies were genotyped. These included 391 Myzus persicae males that were genotyped at three X-linked loci and 538 males from Sitobion clones that were genotyped at five informative X-linked loci. Our results show no departure from clonality in parthenogenetic generations of aphids of the tribe Macrosiphini: no recombinant genotypes were observed in parthenogenetically produced males or females.

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Dotsenko, Iryna. "On the position of parthenogenetic vertebrates in the evolutionary flow and the applicability of species concept to them." Novitates Theriologicae, no. 12 (June 16, 2021): 140–52. http://dx.doi.org/10.53452/nt1224.

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The review is devoted to the analysis of literature sources considering the concepts of "species" and its criteria, "speciation", "reticulate evolution" and "Darwinian evolution", "divergence", "hybridization", and "parthenogenesis". The evolutionary fate and place of parthenogenetic organisms (in particular, among vertebrates) in the general evolutionary flow are considered. The reasons for the predominance of bisexual reproduction despite the obvious energetic and quantitative benefits of parthenogenesis are analysed. The applicability of the term "species" to parthenogenetic organisms is considered, considering their discrepancy with the main (genetic and reproductive) species criteria according to most concepts.

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Lackmann, Alec R., Daniel C. McEwen, and Malcolm G. Butler. "Evidence of parthenogenetic populations from the Paratanytarsus laccophilus species group (Diptera: Chironomidae) in the Alaskan Arctic." CHIRONOMUS Journal of Chironomidae Research, no. 33 (September 13, 2020): 48–58. http://dx.doi.org/10.5324/cjcr.v0i33.3478.

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Parthenogenesis, reproduction without fertilization, is not common in the Chironomidae (Diptera), a family of insects with more than 6,000 described species. Nonetheless, parthenogenetic species and strains have been documented in at least three subfamilies (the Chironominae, Orthocladiinae, and Telmatogoninae), spanning 17 genera and ~30 species. One such species, Paratanytarsus laccophilus Edwards 1929, is known to be parthenogenetic in a small portion of its range in Finland, with most other European populations of this species showing evidence of sexual reproduction. We present evidence of parthenogenetic populations from the Paratanytarsus laccophilus species group in the Nearctic, specifically a High Arctic site near Utqiaġvik (formerly Barrow), Alaska. During May-July of 2015 and 2016, we sampled emerging adult chironomids and pupal exuviae daily to document insect emergence phenologies. Across 15 local populations, all 623 pupal exuviae collected from the P. laccophilus species group were female. Larvae reared from two populations under controlled temperature treatments emerged as female adults (N=37). When isolated, these reared female adults oviposited, and eggs hatched successfully. These progeny were reared for another 12-13 days, reaching second instar larvae when they were preserved at the end of our field season. Taken together, this evidence strongly indicates parthenogenesis from the P. laccophilus species group at this location. This species was not previously documented at Utqiaġvik. Although parthenogenetic, their emergence at this location was highly synchronized. In the harsh environment of arctic Alaska, the fitness rewards of parthenogenesis are likely great. Indeed, chironomid parthenogenesis in the northern hemisphere is most commonly documented from far-northern extremes and in extreme habitats.

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Pannebakker, Bart A., Laas P. Pijnacker, Bas J. Zwaan, and Leo W. Beukeboom. "Cytology of Wolbachia-induced parthenogenesis in Leptopilina clavipes (Hymenoptera: Figitidae)." Genome 47, no. 2 (April 1, 2004): 299–303. http://dx.doi.org/10.1139/g03-137.

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Parthenogenesis induced by cytoplasmatically inherited Wolbachia bacteria has been found in a number of arthropod species, mainly Hymenoptera. Previously, two different forms of diploidy restoration have been reported to underlie parthenogenesis induction in Hymenoptera by Wolbachia. Both are a form of gamete duplication, but each differs in their timing. We investigated the cytology of the early embryonic development of a Wolbachia-infected strain of the parasitoid wasp Leptopilina clavipes and compared it with that of an uninfected sexual strain. Both strains have a similar meiosis. In the infected parthenogenetic strain, diploidy is restored by anaphase restitution during the first somatic mitosis, similar to Trichogramma, but not to Muscidifurax. Our results confirm the occurrence of different cytological mechanisms of diploidy restoration associated with parthenogenesis-inducing Wolbachia in the order Hymenoptera.Key words: gamete duplication, Leptopilina clavipes, parthenogenesis, thelytoky, Wolbachia.

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Gasanov, Eugene V., and Alexey V. Katz. "Facultative Parthenogenesis in a Diamondback Water Snake (Nerodia rhombifer)." Russian Journal of Herpetology 27, no. 6 (November 21, 2020): 341–47. http://dx.doi.org/10.30906/1026-2296-2020-27-6-341-347.

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Here we describe a case of facultative parthenogenesis in a diamondback water snake (Nerodia rhombifer). An adult female N. rhombifer kept in captivity produced four unfertilized ova, one stillborn and one live neonate in July 2016. The neonates had characteristic abnormalities in morphology and were determined as males, suggestive of a parthenogenetic event. Stillborn and live neonates along with the mother and four unrelated N. rhombifer were genetically screened at twelve microsatellite loci. Results confirmed that the reproductive event represented a case of facultative parthenogenesis. In light of previous reports of facultative parthenogenesis in the genera Nerodia and Thamnophis, these results suggest that this reproductive mode may be a widespread phenomenon in the Natricinae as a whole.

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Shi-Qi, Zhou, Qian De-Qi, and Cao Xiu-Yun. "Induction of parthenogenesis, and chromosome behavior in plants of parthenogenetic origin in cotton (Gossypium hirsutum)." Genome 34, no. 2 (April 1, 1991): 255–60. http://dx.doi.org/10.1139/g91-040.

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Different chemical, physical, and biological treatments were applied to emasculated flower buds of cotton hybrids (Gossypium hirsutum, 2n = 4x = 52) of various genotypes with the purpose of inducing haploid parthenogenesis. Of the treatments applied, the most effective chemical treatment was 0.2% colchicine in 0.2% dimethyl sulfoxide (1.22% parthenogenetic seed set), the most effective physical treatment was high temperature (2.66% parthenogenetic seed set), and the most effective biological treatment was pollination with Hibiscus cannabinus pollen (2.33% parthenogenetic seed set). In the progeny of five plants of parthenogenetic origin, chromosome number and meiotic behavior were studied. All were mixoploids at the dihaploid level and yet set bolls almost like normal allotetraploids. Chromosome numbers ranged from 12 to 56 in the root tips within plants, with a somewhat less pronounced variation between pollen mother cells. At meiotic metaphase I in pollen mother cells 89.8% of the chromosomes were associated. Of the bivalents 23.3% showed AA pairing, 18.7% showed DD pairing, and 18.4% showed AD pairing. Trivalents and higher multivalents involved 29.4% of the chromosomes, and 10.2% were univalents. Anaphase I segregation was often unequal. Yet fertility was as high as in the allotetraploid. It is possible that the second generation was formed by parthenogenesis after restitution in the embryonic mother cells.Key words: Gossypium hirsutum, cotton, parthenogenesis, mixoploidy, meiosis fertility.

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Aron, S., I. Timmermans, and M. Pearcy. "Ant queens adjust egg fertilization to benefit from both sexual and asexual reproduction." Biology Letters 7, no. 4 (February 9, 2011): 571–73. http://dx.doi.org/10.1098/rsbl.2010.1189.

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An enduring problem in evolutionary biology is the near ubiquity of sexual reproduction despite the inherent cost of transmitting only half the parent's genes to progeny. Queens of some ant species circumvent this cost by using selectively both sexual reproduction and parthenogenesis: workers arise from fertilized eggs, while new queens are produced by parthenogenesis. We show that queens of the ant Cataglyphis cursor maximize the transmission rate of their genes by regulating the proportion of fertilized and parthenogenetic eggs laid over time. Parthenogenetic offspring are produced in early spring, when workers raise the brood into sexuals. After the mating period, queens lay mostly fertilized eggs that will be reared as the non-reproductive caste.

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Fujita, Matthew K., Sonal Singhal, Tuliana O. Brunes, and Jose A. Maldonado. "Evolutionary Dynamics and Consequences of Parthenogenesis in Vertebrates." Annual Review of Ecology, Evolution, and Systematics 51, no. 1 (November 2, 2020): 191–214. http://dx.doi.org/10.1146/annurev-ecolsys-011720-114900.

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Parthenogenesis is asexual reproduction without any required participation from males and, as such, is a null model for sexual reproduction. In a comparative context, we can expand our understanding of the evolution and ecology of sex by investigating the consequences of parthenogenesis. In this review, we examine the theoretical predictions of and empirical results on the evolution of asexual reproduction in vertebrates, focusing on recent studies addressing the origins and geographic spread of parthenogenetic lineages and the genomic consequences of an asexual life history. With advances in computational methods and genome technologies, researchers are poised to make rapid and significant progress in studying the origin and evolution of parthenogenesis in vertebrates, thus providing an important perspective on understanding biodiversity patterns of both asexual and sexual populations.

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Angus, Robert B., and Fenglong Jia. "Triploidy in Chinese parthenogenetic Helophorus orientalis Motschulsky, 1860, further data on parthenogenetic H. brevipalpis Bedel, 1881 and a brief discussion of parthenogenesis in Hydrophiloidea (Coleoptera)." Comparative Cytogenetics 14, no. 1 (January 13, 2020): 1–10. http://dx.doi.org/10.3897/compcytogen.v14i1.47656.

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The chromosomes of triploid parthenogenetic Helophorus orientalis Motschulsky, 1860 are described from material from two localities in Heilongjiang, China. 3n = 33. All the chromosomes have clear centromeric C-bands, and in the longest chromosome one replicate appears to be consistently longer than the other two. The chromosomes of additional triploid parthenogenetic H. brevipalpis Bedel, 1881, from Spain and Italy, are described. In one Italian population one of the autosomes is represented by only two replicates and another appears more evenly metacentric than in material from Spain and the other Italian locality. Parthenogenetic and bisexual specimens of H. orientalis are illustrated, along with Pleistocene fossil material. Parthenogenetic H. brevipalpis is also illustrated. Parthenogenesis in Hydrophiloidea is discussed. It appears to be rare and, in all cases has been detected by chromosomal analysis of populations in which males are unexpectedly scarce. Parthenogenesis is suspected in Helophorus aquila Angus et al., 2014, from northern Qinghai (China), which should be verified in further studies.

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Lamb, Richard Y., and Robert B. Willey. "Cytological mechanisms of thelytokous parthenogenesis in insects." Genome 29, no. 2 (April 1, 1987): 367–69. http://dx.doi.org/10.1139/g87-062.

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The eight female parthenogenetic mechanisms recognized in insects are organized under the broad categories "ploidy restoration" and "ploidy stasis." Each term replaces three imprecise and inappropriate existing names. Of the eight mechanisms, two are given names for the first time, and a table brings together all mechanisms in a new manner that shows the exact point in meiosis during which the DNA is doubled. Key words: insect reproduction, parthenogenesis, parthenogenetic mechanisms.

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Burke, Nathan W., and Russell Bonduriansky. "The geography of sex: sexual conflict, environmental gradients and local loss of sex in facultatively parthenogenetic animals." Philosophical Transactions of the Royal Society B: Biological Sciences 373, no. 1757 (August 27, 2018): 20170422. http://dx.doi.org/10.1098/rstb.2017.0422.

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Obligately asexual organisms tend to occur at higher altitudes or latitudes and occupy larger ranges than their obligately sexual relatives—a phenomenon called geographical parthenogenesis. Some facultatively parthenogenetic organisms that reproduce both sexually and asexually also exhibit spatial variation in reproductive mode. Theory suggests that sexual conflict and mate limitation can determine the relative frequency of sex in facultative parthenogens, but the effect of these dynamics on spatial distributions is unknown. Here, we use individual-based models to investigate whether these dynamics can generate local differences in the reproductive mode in a facultatively parthenogenetic metapopulation occupying an environmental gradient. We find that selection for resistance and high fecundity creates positive epistasis in virgin females between a mutant allele for parthenogenesis and alleles for resistance, resulting in female-biased sex ratios and higher resistance and coercion towards the productive ‘core’ of the metapopulation. However, steeper environmental gradients, which lead to lower density and less mating at the ‘edge’, generate female bias without promoting coercion or resistance. Our analysis shows that local adaptation of facultatively parthenogenetic populations subject to sexual conflict and productivity gradients can generate striking spatial variation suggesting new patterns for empirical investigation. These findings could also help to explain the rarity of facultative parthenogenesis in animals. This article is part of the theme issue ‘Linking local adaptation with the evolution of sex differences'.

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Oliveira, F., F. Perecin, F. Meireles, J. Sangalli, Y. Watanabe, A. Miglino, and A. Assis Neto. "105 COMPARATIVE ULTRASTRUCTURE OF IN VITRO-PRODUCED BOVINE BLASTOCYSTS (BOS INDICUS) DERIVED FROM IN VITRO FERTILIZATION, SNC, AND PARTHENOGENESIS." Reproduction, Fertility and Development 25, no. 1 (2013): 200. http://dx.doi.org/10.1071/rdv25n1ab105.

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It is known that embryos produced in vitro may have structural alterations that often compromise the normal embryo development, generating a high rate of pregnancy loss. The study of these changes is of great importance because it may elucidate the cause of embryonic loss during the first trimester of pregnancy. Thus, the objective of this study was to characterize and compare ultrastructurally bovine blastocysts in the 7th day of development produced by IVF, cloning by somatic cell nuclear transfer (SCNT), and parthenogenesis. In vitro-produced embryos were derived from in vitro-matured oocytes. The somatic cell used to make cloning was fibroblasts of adult cows, and the protocol for parthenogenetic activation of the embryos was done with ionomycin-DMAP. The blastocysts derived from the different experimental groups were fixed in 2.5% glutaraldehyde and processed for transmission electron microscopy evaluation. The results showed that blastocysts derived by SNC and parthenogenesis exhibited a significantly reduced size; the inner cell mass and the blastocoel were not well defined compared with IVF embryos, indicating a less-advanced state of development. Furthermore, organelles of blastocysts derived from SCNT and parthenogenesis were fewer in number and had changes in form, when compared with IVF blastocysts. In parthenogenetic embryos there was the presence of phagosomes, suggesting a high degradation activity of cellular. Mitochondria showed the most significant changes. Although they occur in large quantities in all blastocysts, the morphology of them was impaired in SNC and parthenogenetic embryos (vacuolization, abnormal shape). Such modifications could suggest changes in mitochondria functionality, which may decrease cellular metabolic activity. Thus, we find that the D7 blastocysts derived from SCNT and parthenogenesis showed several ultrastructural differences compared with IVF embryos, with particular reference to a reduced number and morphology of embryo organelles.

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Budiariati, Vista, Dwi Budiono, Mokhamad Fahrudin, Berry Juliandi, Ratih Rinendyaputri, and Arief Boediono. "Production and Characterization of Mouse Diploid Parthenogenetic Blastocyst Developed in Phosphate-Free Medium." HAYATI Journal of Biosciences 27, no. 2 (April 1, 2020): 89. http://dx.doi.org/10.4308/hjb.27.2.89.

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Parthenogenesis is an artificial oocytes activation process without paternal contribution. Blastocyst, derived from parthenogenesis, is one of potential source for pluripotent stem cell propagation. Unfortunately, previous studies reported that parthenogenetic embryo did not achieve exhilarating blastocyst rate. One of the component that predicted inhibit parthenogenetic embryo development is phosphate. Therefore, we try to modify culture medium in order to overcome that problem. The aim of this research was to produce and analyze the characteristics of parthenogenetic blastocyst developed in phosphate-free medium. Mouse oocytes obtained from adult female DDY by superovulation. The activator was strontium chloride 10 mM and diploidization with cytochalasin B 5 μg/ml. Medium for activation and culture medium were modified rat 1 cell embryo medium (MR1ECM) which is phosphate free. The results showed that parthenotes that were cultured in phosphate free medium reached higher blastocyst rate compared to the other groups. The increase of phosphate in culture medium lead to impaired parthenogenetic embryos development. Further experiment was made to analyze the differences between fertilized and parthenogenetic embryo in this medium. The experiment showed that diploid parthenogenetic could achieve high blastocyst rate (30.9±1.3%). The quality of diploid parthenogenetic blastocyst, based on cells number, viability, and ICM ratio, was lower than fertilized blastocyst.

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Petrosyan, Varos, Fedor Osipov, Vladimir Bobrov, Natalia Dergunova, Andrey Omelchenko, Alexander Varshavskiy, Felix Danielyan, and Marine Arakelyan. "Species Distribution Models and Niche Partitioning among Unisexual Darevskia dahli and Its Parental Bisexual (D. portschinskii, D. mixta) Rock Lizards in the Caucasus." Mathematics 8, no. 8 (August 10, 2020): 1329. http://dx.doi.org/10.3390/math8081329.

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Among vertebrates, true parthenogenesis is known only in reptiles. Parthenogenetic lizards of the genus Darevskia emerged as a result of the hybridization of bisexual parental species. However, uncertainty remains about the mechanisms of the co-existence of these forms. The geographical parthenogenesis hypothesis suggests that unisexual forms can co-exist with their parental species in the “marginal” habitats. Our goal is to investigate the influence of environmental factors on the formation of ecological niches and the distribution of lizards. For this reason, we created models of species distribution and ecological niches to predict the potential geographical distribution of the parthenogenetic and its parental species. We also estimated the realized niches breadth, their overlap, similarities, and shifts in the entire space of predictor variables. We found that the centroids of the niches of the three studied lizards were located in the mountain forests. The “maternal” species D. mixta prefers forest habitats located at high elevations, “paternal” species D. portschinskii commonly occurs in arid and shrub habitats of the lower belt of mountain forests, and D. dahli occupies substantially an intermediate or “marginal” position along environmental gradients relative to that of its parental species. Our results evidence that geographical parthenogenesis partially explains the co-existence of the lizards.

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Ochkalova, Sofia, Vitaly Korchagin, Andrey Vergun, Avel Urin, Danil Zilov, Sergei Ryakhovsky, Anastasiya Girnyk, et al. "First Genome of Rock Lizard Darevskia valentini Involved in Formation of Several Parthenogenetic Species." Genes 13, no. 9 (September 1, 2022): 1569. http://dx.doi.org/10.3390/genes13091569.

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The extant reptiles are one of the most diverse clades among terrestrial vertebrates and one of a few groups with instances of parthenogenesis. Due to the hybrid origin of parthenogenetic species, reference genomes of the parental species as well as of the parthenogenetic progeny are indispensable to explore the genetic foundations of parthenogenetic reproduction. Here, we report on the first genome assembly of rock lizard Darevskia valentini, a paternal species for several parthenogenetic lineages. The novel genome was used in the reconstruction of the comprehensive phylogeny of Squamata inferred independently from 7369 trees of single-copy orthologs and a supermatrix of 378 conserved proteins. We also investigated Hox clusters, the loci that are often regarded as playing an important role in the speciation of animal groups with drastically diverse morphology. We demonstrated that Hox clusters of D. valentini are invaded with transposons and contain the HoxC1 gene that has been considered to be lost in the amniote ancestor. This study provides confirmation for previous works and releases new genomic data that will contribute to future discoveries on the mechanisms of parthenogenesis as well as support comparative studies among reptiles.

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Conner, Joann A., Muruganantham Mookkan, Heqiang Huo, Keun Chae, and Peggy Ozias-Akins. "A parthenogenesis gene of apomict origin elicits embryo formation from unfertilized eggs in a sexual plant." Proceedings of the National Academy of Sciences 112, no. 36 (August 24, 2015): 11205–10. http://dx.doi.org/10.1073/pnas.1505856112.

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Apomixis is a naturally occurring mode of asexual reproduction in flowering plants that results in seed formation without the involvement of meiosis or fertilization of the egg. Seeds formed on an apomictic plant contain offspring genetically identical to the maternal plant. Apomixis has significant potential for preserving hybrid vigor from one generation to the next in highly productive crop plant genotypes. Apomictic Pennisetum/Cenchrus species, members of the Poaceae (grass) family, reproduce by apospory. Apospory is characterized by apomeiosis, the formation of unreduced embryo sacs derived from nucellar cells of the ovary and, by parthenogenesis, the development of the unreduced egg into an embryo without fertilization. In Pennisetum squamulatum (L.) R.Br., apospory segregates as a single dominant locus, the apospory-specific genomic region (ASGR). In this study, we demonstrate that the PsASGR-BABY BOOM-like (PsASGR-BBML) gene is expressed in egg cells before fertilization and can induce parthenogenesis and the production of haploid offspring in transgenic sexual pearl millet. A reduction of PsASGR-BBML expression in apomictic F1 RNAi transgenic plants results in fewer visible parthenogenetic embryos and a reduction of embryo cell number compared with controls. Our results endorse a key role for PsASGR-BBML in parthenogenesis and a newly discovered role for a member of the BBM-like clade of APETALA 2 transcription factors. Induction of parthenogenesis by PsASGR-BBML will be valuable for installing parthenogenesis to synthesize apomixis in crops and will have further application for haploid induction to rapidly obtain homozygous lines for breeding.

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Nokkala, Seppo, Valentina G. Kuznetsova, Peppi Pietarinen, and Christina Nokkala. "Evolutionary Potential of Parthenogenesis—Bisexual Lineages within Triploid Apomictic Thelytoky in Cacopsylla ledi (Flor, 1861) (Hemiptera, Psylloidea) in Fennoscandia." Insects 13, no. 12 (December 11, 2022): 1140. http://dx.doi.org/10.3390/insects13121140.

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A widely accepted hypothesis is that parthenogenesis is an evolutionary dead end since it is selectively advantageous in the short term only but results in lowered diversification rates. Triploid apomictic parthenogenesis might represent an exception, as in favorable environments, triploid females are able to produce rare males and diploid females. The aim of the present study was to analyze the modes of reproduction and their evolutionary implications in the parthenogenetic psyllid Cacopsylla ledi (Flor, 1861) from Fennoscandia. The cytogenetic assessment of ploidy levels and the analysis of the COI haplotype revealed two geographically separated bisexual lineages implying genuine bisexual populations. The southern lineage occurring south of latitude 65° N in Finland showed a COI haplotype different from that of parthenogenetic triploids in the same population but identical to the haplotype of specimens in a genuine bisexual population in the Czech Republic. This allows us to suggest that bisexuals in southern Fennoscandia represent the original bisexual C. ledi. By contrast, in the northern bisexual lineage north of latitude 65° N, rare males and diploid females carried the same haplotype as triploids in the same population, having been produced by the triploids. In the Kola Peninsula, a genuine bisexual population of presumably rare male/diploid female origin was discovered. As this population is geographically isolated from populations of the ancestral bisexual C. ledi, it can develop into a new bisexual species through peripatric speciation during evolution. Our findings demonstrate that apomictic triploid parthenogenesis is not necessarily an evolutionary dead end but is able to lead to the emergence of a new bisexual species of parthenogenetic origin.

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Shurley, Britton. "Parthenogenesis." Massachusetts Review 58, no. 2 (2017): 321. http://dx.doi.org/10.1353/mar.2017.0051.

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Mezhzherin, S. V., Yu Yu Chayka, R. P. Vlasenko, E. I. Zhalay, O. V. Rostovskaya, and O. V. Garbar. "The Alternative Distribution of Related Earthworms Aporrectodea caliginosa and A. trapezoides (Oligochaeta, Lumbricidae) in Ukraine as a Case of Geographical Parthenogenesis." Zoodiversity 55, no. 3 (2021): 185–94. http://dx.doi.org/10.15407/zoo2021.03.185.

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Geographical parthenogenesis describes phenomenon when parthenogenetic hybrid forms or species have larger distribution areas or higher abundance than their amphimictic parental species, especially in climatically unfavorable conditions. This phenomenon was studied in Ukraine for the pair species of earthworms Aporrectodea сaliginosa (Savigny, 1826) s. l. We found that the hermaphroditic amphimictic A. caliginosa clearly predominates in the northern and western regions, and the apomictic parthenogenetic A. trapezoides (Duges, 1828) in the southern and eastern regions with a continental arid climate. In the sample sets of A. сaliginosa–A. trapezoides group, usually one of the species sharply predominated, and the equality of their abundance was very rare. The reason for this fact is both the alternative geographical distribution and the ability of A. trapezoides to form populations in habitats unfavorable for A. caliginosa. In general, the situation in this group agrees with the classical model of geographic parthenogenesis and confirms the high adaptive potential of apomictic organisms. This fact once again raises the question of non-adaptive reasons for the exclusion of the apomictic reproduction in highly organized animals.

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HINO, AKINA, TERUHISA TANAKA, MAHO TAKAISHI, YUMIKO FUJII, JUAN E. PALOMARES-RIUS, KOICHI HASEGAWA, HARUHIKO MARUYAMA, and TAISEI KIKUCHI. "Karyotype and reproduction mode of the rodent parasite Strongyloides venezuelensis." Parasitology 141, no. 13 (August 4, 2014): 1736–45. http://dx.doi.org/10.1017/s0031182014001036.

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SUMMARYStrongyloides venezuelensis is a parasitic nematode that infects rodents. Although Strongyloides species described to date are known to exhibit parthenogenetic reproduction in the parasitic stage of their life cycle and sexual reproduction in the free-living stage, we did not observe any free-living males in S. venezuelensis in our strain, suggesting that the nematode is likely to depend on parthenogenetic reproduction. We confirmed by cytological analysis that S. venezuelensis produces eggs by parthenogenesis during the parasitic stage of its life cycle. Phylogenetic analysis using nearly the full length of 18S and D3 region of 28S ribosomal RNA gene suggested that S. venezuelensis is distantly related to another rodent parasite, namely Strongyloides ratti, but more closely related to a ruminant parasite, Strongyloides papillosus. Karyotype analysis revealed S. venezuelensis reproduces with mitotic parthenogenesis, and has the same number of chromosomes as S. papillosus (2n = 4), but differs from S. ratti (2n = 6) in this regard. These results, taken together, suggest that S. venezuelensis evolved its parasitism for rodents independently from S. ratti and, therefore, is likely to have a different reproductive strategy.

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Sharbel, Timothy F., Leo W. Beukeboom, and Laas P. Pijnacker. "Multiple supernumerary chromosomes in the pseudogamous parthenogenetic flatworm Polycelis nigra: lineage markers or remnants of genetic leakage?" Genome 40, no. 6 (December 1, 1997): 850–56. http://dx.doi.org/10.1139/g97-810.

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Polycelis nigra is a free-living simultaneous hermaphroditic flatworm that has amphimictic and pseudogamous parthenogenetic biotypes. Sexual individuals are always diploid (2n = 16) and pseudogamous parthenogens are polyploid (usually triploid). Two types of supernumerary chromosomes are found in parthenogens, those resembling autosomes ("A-like") and typical B chromosomes, both of which reach frequencies in populations of close to 100%. Experiments measuring the transmission rates of the B chromosomes indicated that they are potentially inherited via the male line, escaping expulsion by pseudogamous parthenogenesis. This study used the C-banding technique to demonstrate (i) that there is a single morphologically distinct B chromosome (B1) and (ii) that there are two "A-like" chromosomes that can be considered B chromosomes (B2 and B3) and which are not simple polysomics of one of the eight autosomes. As there is no genetic exchange between pseudogamous parthenogenetic lineages, two different individuals carrying a similar B morph must either have received it through common ancestry (a lineage marker) or have acquired it horizontally from another parthenogenetic lineage (leakage). C-banding further revealed intra-individual heteromorphy for band regions on chromosomes 5 and 8. This supports the karyotypic observation that oogenesis is preceded by premeiotic chromosome doubling followed by pairing of replicate homologues.Key words: B chromosome, C-banding, heterochromatin, heteromorphy, pseudogamous parthenogenesis.

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Oh, Hyun Ju, Byeong Chun Lee, and Min Kyu Kim. "Optimal Treatment of 6-Dimethylaminopurine Enhances the In Vivo Development of Canine Embryos by Rapid Initiation of DNA Synthesis." International Journal of Molecular Sciences 22, no. 14 (July 20, 2021): 7757. http://dx.doi.org/10.3390/ijms22147757.

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Artificial activation of oocytes is an important step for successful parthenogenesis and somatic cell nuclear transfer (SCNT). Here, we investigated the initiation of DNA synthesis and in vivo development of canine PA embryos and cloned embryos produced by treatment with 1.9 mM 6-dimethylaminopurine (6-DMAP) for different lengths of time. For experiments, oocytes for parthenogenesis and SCNT oocytes were cultured for 4 min in 10 μM calcium ionophore, and then divided into 2 groups: (1) culture for 2 h in 6-DMAP (DMAP-2h group); (2) culture for 4 h in DMAP (DMAP-4h group). DNA synthesis was clearly detected in all parthenogenetic (PA) embryos and cloned embryos incorporated BrdU 4 h after activation in DMAP-2h and DMAP-4h groups. In vivo development of canine parthenogenetic fetuses was observed after embryo transfer and the implantation rates of PA embryos in DMAP-2h were 34%, which was significantly higher than those in DMAP-4h (6.5%, p < 0.05). However, in SCNT, there was no significant difference in pregnancy rate (DMAP-2h: 41.6% vs. DMAP-4h: 33.3%) and implantation rates (DMAP-2h: 4.94% vs. DMAP-4h: 3.19%) between DMAP-2h and DMAP-4h. In conclusion, the use of DMAP-2h for canine oocyte activation may be ideal for the in vivo development of PA zygotes, but it was not more effective in in vivo development of canine reconstructed SCNT oocytes. The present study demonstrated that DMAP-2h treatment on activation of canine parthenogenesis and SCNT could effectively induce the onset of DNA synthesis during the first cell cycle.

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Cocco, J., A. R. Butnariu, E. Bessa, and A. Pasini. "Sex produces as numerous and long-lived offspring as parthenogenesis in a new parthenogenetic insect." Canadian Journal of Zoology 91, no. 3 (March 2013): 187–90. http://dx.doi.org/10.1139/cjz-2012-0289.

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Sex is a costly form of reproduction compared with parthenogenesis, but sex persists because of the more resistant and competitive descendants that it produces. We obtained thelytokous offspring from unmated female Doru lineare (Eschscholtz, 1822) earwigs, a species of insect in which parthenogenesis has never before been reported, and found that their number and survival rate did not differ from offspring of mated females. Current hypotheses support advantages of sex or parthenogenesis, but never equilibrium between them like the one reported in this paper. We suggest that parthenogenesis is how females multiply their entire genome and renew themselves.

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Noyes, Richard D., and Loren H. Rieseberg. "Two Independent Loci Control Agamospermy (Apomixis) in the Triploid Flowering Plant Erigeron annuus." Genetics 155, no. 1 (May 1, 2000): 379–90. http://dx.doi.org/10.1093/genetics/155.1.379.

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Abstract Asexual seed production (agamospermy) via gametophytic apomixis in flowering plants typically involves the formation of an unreduced megagametophyte (via apospory or diplospory) and the parthenogenetic development of the unreduced egg cell into an embryo. Agamospermy is almost exclusively restricted to polyploids. In this study, the genetic basis of agamospermy was investigated in a segregating population of 130 F1's from a cross between triploid (2n = 27) agamospermous Erigeron annuus and sexual diploid (2n = 18) E. strigosus. Correlations between markers and phenotypes and linkage analysis were performed on 387 segregating amplified fragment length polymorphisms (AFLPs). Results show that four closely linked markers with polysomic inheritance are significantly associated with parthenogenesis and that 11 cosegregating markers with univalent inheritance are completely associated with diplospory. This indicates that diplospory and parthenogenesis are unlinked and inherited independently. Further, the absence of agamospermy in diploid F1's appears to be best explained by a combination of recessive-lethal gametophytic selection against the parthenogenetic locus and univalent inheritance of the region bearing diplospory. These results may have major implications for attempts to manipulate agamospermy for agricultural purposes and for interpreting the evolution of the trait.

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Mandrioli, M., E. Zanetti, A. Nardelli, and G. C. Manicardi. "Potential role of the heat shock protein 90 (hsp90) in buffering mutations to favour cyclical parthenogenesis in the peach potato aphid Myzus persicae (Aphididae, Hemiptera)." Bulletin of Entomological Research 109, no. 4 (September 12, 2018): 426–34. http://dx.doi.org/10.1017/s0007485318000688.

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AbstractHeat-shock proteins 90 (hsp90s) are a class of molecules able to stabilize a network of ‘client’ proteins that are involved in several processes. Furthermore, recent studies indicated that mutations in the hsp90-encoding gene induce a wide range of phenotypic abnormalities, which have been interpreted as an increased sensitivity of different developmental pathways to hidden/cryptic mutations. In order to verify the role of hsp90 in aphids, we amplified and sequenced the hsp90 gene in 17 lineages of the peach potato aphid Myzus persicae (Sulzer, 1776) looking for the presence of mutations. In particular, we compared lineages with different reproductive modes (obligate vs. cyclical parthenogenesis), propensity to develop winged females and karyotype stability. Differently from the cyclical parthenogenetic lineages that possessed functional hsp90 genes, the seven analysed asexual lineages showed severe mutations (including frameshift and non-sense mutations). In vivo functional assays with the hsp90-inhibitor geldanamycin showed that some lineages with cyclical parthenogenesis may lose their ability to induce sexuales in the absence of active hsp90 revealing the presence of cryptic mutations in their genomes. As a whole, our data suggest that hsp90 could play in aphids a role in buffering hidden/cryptic mutations that disrupt cyclical parthenogenesis.

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Boyer, Loreleï, Roula Jabbour-Zahab, Pauline Joncour, Sylvain Glémin, Christoph R. Haag, and Thomas Lenormand. "Asexual male production by ZW recombination in Artemia parthenogenetica." Evolution 77, no. 1 (December 8, 2022): 1–12. http://dx.doi.org/10.1093/evolut/qpac008.

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Abstract In some asexual species, parthenogenetic females occasionally produce males, which may strongly affect the evolution and maintenance of asexuality if they cross with related sexuals and transmit genes causing asexuality to their offspring (“contagious parthenogenesis”). How these males arise in the first place has remained enigmatic, especially in species with sex chromosomes. Here, we test the hypothesis that rare, asexually produced males of the crustacean Artemia parthenogenetica are produced by recombination between the Z and W sex chromosomes during non-clonal parthenogenesis, resulting in ZZ males through loss of heterozygosity at the sex determination locus. We used RAD-sequencing to compare asexual mothers with their male and female offspring. Markers on several sex-chromosome scaffolds indeed lost heterozygosity in all male but no female offspring, suggesting that they correspond to the sex-determining region. Other sex-chromosome scaffolds lost heterozygosity in only a part of the male offspring, consistent with recombination occurring at a variable location. Alternative hypotheses for the production of these males (such as partial or total hemizygosity of the Z) could be excluded. Rare males are thus produced because recombination is not entirely suppressed during parthenogenesis in A. parthenogenetica. This finding may contribute to explaining the maintenance of recombination in these asexuals.

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Maccari, Marta, Francisco Amat, Francisco Hontoria, and Africa Gómez. "Laboratory generation of new parthenogenetic lineages supports contagious parthenogenesis inArtemia." PeerJ 2 (June 17, 2014): e439. http://dx.doi.org/10.7717/peerj.439.

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Mullard, Asher. "Inadvertent parthenogenesis." Nature Reviews Molecular Cell Biology 8, no. 9 (September 2007): 677. http://dx.doi.org/10.1038/nrm2251.

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Huigens, M. E., R. F. Luck, R. H. G. Klaassen, M. F. P. M. Maas, M. J. T. N. Timmermans, and R. Stouthamer. "Infectious parthenogenesis." Nature 405, no. 6783 (May 2000): 178–79. http://dx.doi.org/10.1038/35012066.

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Chen, Jine, Xin Du, Xia Xu, Sheng Zhang, Lusong Yao, Xiuling He, and Yongqiang Wang. "Comparative Proteomic Analysis Provides New Insights into the Molecular Basis of Thermal-Induced Parthenogenesis in Silkworm (Bombyx mori)." Insects 14, no. 2 (January 28, 2023): 134. http://dx.doi.org/10.3390/insects14020134.

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Artificial parthenogenetic induction via thermal stimuli in silkworm is an important technique that has been used in sericultural production. However, the molecular mechanism underlying it remains largely unknown. We have created a fully parthenogenetic line (PL) with more than 85% occurrence and 80% hatching rate via hot water treatment and genetic selection, while the parent amphigenetic line (AL) has less than 30% pigmentation rate and less than 1% hatching rate when undergoing the same treatment. Here, isobaric tags for relative and absolute quantitation (iTRAQ)-based analysis were used to investigate the key proteins and pathways associated with silkworm parthenogenesis. We uncovered the unique proteomic features of unfertilized eggs in PL. In total, 274 increased abundance proteins and 211 decreased abundance proteins were identified relative to AL before thermal induction. Function analysis displayed an increased level of translation and metabolism in PL. After thermal induction, 97 increased abundance proteins and 187 decreased abundance proteins were identified. An increase in stress response-related proteins and decrease in energy metabolism suggested that PL has a more effective response to buffer the thermal stress than AL. Cell cycle-related proteins, including histones, and spindle-related proteins were decreased in PL, indicating an important role of this decrease in the process of ameiotic parthenogenesis.

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Pijnacker, Laas, and (Hans) van der Beek. "Maintenance of genetic variation in automictic root-knot nematodes." Nematology 10, no. 3 (2008): 313–21. http://dx.doi.org/10.1163/156854108783900221.

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AbstractDifferences in amplified fragment length polymorphisms (AFLP) between isolates and between mono-female lines of facultative automictic Meloidogyne hapla race A and obligate apomictic M. incognita were determined to test the hypothesis that inverted meiosis occurs. DNA of the parthenogenetic nematode lines were extracted from juveniles, which had been propagated for two generations, allowing males in M. hapla lines to be formed and fertilisation to take place. Based on AFLP analysis, the genetic distance between mono-female lines of M. incognita appeared to be almost nil. By contrast, the genetic distance between isolates and between mono-female lines after seven generations of parthenogenesis of M. hapla was larger. The genetic distance between two mono-female lines of M. hapla, after one generation of parthenogenesis and originating from one line with six generations of parthenogenesis, was larger than the distance between M. incognita lines and the smallest distance between M. hapla lines. The numbers of DNA fragments appeared to be equally variable between lines within a single M. hapla isolate as between various isolates of M. hapla. This maintenance of genetic variation in M. hapla is likely to be caused by the combination of post-reduction in an inverted meiosis, due to chromosomes with diffuse centromeres, and the fusion of the haploid products of the second meiotic division.

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Coates, Kathryn A. "Widespread polyploid forms off Lumbricillus lineatus (Müller) (Enchytraeidae: Oligochaeta): comments on polyploidism in the enchytraeids." Canadian Journal of Zoology 73, no. 9 (September 1, 1995): 1727–34. http://dx.doi.org/10.1139/z95-204.

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Studies of a small fresh collection of the marine intertidal enchytraeid oligochaete Lumbricillus lineatus (Müller) and taxonomic collections from 27 additional locations in Europe, Canada, and Australia reveal the presence of morphotypes corresponding to parthenogenetic autopolyploid forms, triploid, tetraploid, and pentaploid, of the species in all the regions represented by the collections. The extension of the range of these cytotypes from Europe to a virtually global distribution raises questions about the significance of parthenogenesis and polyploidism to their invasion of new habitats. Differences in reproduction rates and the ecological breadth of the different ploidy levels are not known. The geographical distribution and abundance of polyploids of L. lineatus, in themselves, do not provide conclusive evidence for the repeated origins of polyploids within the species, but strongly suggest that possibility. General theories link evolutionary polyploidy among animals with parthenogenesis, as seen in the polyploid forms of L. lineatus. However, polyploidism combined with out-crossing underlies the present taxonomic diversity of the family Enchytraeidae.

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Lasee, Becky A., William F. Font, and Daniel R. Sutherland. "Culaeatrema inconstans gen.n., sp.n. (Digenea: Alloereadiidae) from the brook stickleback (Culaea inconstans) in Wisconsin and observations on parthenogenetic populations." Canadian Journal of Zoology 66, no. 6 (June 1, 1988): 1328–33. http://dx.doi.org/10.1139/z88-195.

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Culaeatrema inconstans gen.n., sp.n. is described from the intestine of Culaea inconstans (Kirtland) collected in Wisconsin. Culaeatrema is a small, fusiform, nonspinous trematode resembling both allocreadiins and bunoderins. Culaeatrema is placed in the subfamily Bunoderinae because testes are oblique in position, uterus extends into the posterior region, and vitellaria do not extend beyond the anterior testis. Reproduction in two populations of the new species from Shell and Little Waumandee creeks appears to be parthenogenetic. Parthenogenetic worms exhibited larger phenotypic size, one or both testes lacking in 84% of the examined specimens, lack of spermatozoa, and reduced development of male reproductive structures. A discussion of parthenogenesis in parasitic helminths is included.

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Klotz, C., M. C. Dabauvalle, M. Paintrand, T. Weber, M. Bornens, and E. Karsenti. "Parthenogenesis in Xenopus eggs requires centrosomal integrity." Journal of Cell Biology 110, no. 2 (February 1, 1990): 405–15. http://dx.doi.org/10.1083/jcb.110.2.405.

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Xenopus eggs are laid arrested at second metaphase of meiosis lacking a functional centrosome. Upon fertilization, the sperm provides the active centrosome that is required for cleavage to occur. The injection of purified centrosomes mimics fertilization and leads to tadpole formation (parthenogenesis). In this work we show that the parthenogenetic activity of centrosomes is inactivated by urea concentrations higher than 2 M. The loss of activity is correlated with a progressive destruction of the centriolar cylinder and extraction of proteins. This shows that centrosomes are relatively sensitive to urea since complete protein unfolding and solubilization of proteins normally occurs at urea concentrations as high as 8-10 M. When present, the parthenogenetic activity is always associated with a pelletable fraction showing that it cannot be solubilized by urea. The parthenogenetic activity is progressively inactivated by salt concentrations higher than 2 M (NaCl or KCl). However, only a few proteins are extracted by these treatments and the centrosome ultrastructure is not affected. This shows that both parthenogenetic activity and centrosomal structure are resistant to relatively high ionic strength. Indeed, most protein structures held by electrostatic forces are dissociated by 2 M salt. The loss of parthenogenetic activity produced at higher salt concentrations, while the structure of the centrosome is unaffected, is an apparent paradox. We interpret this result as meaning that the native state of centrosomes is held together by forces that favor functional denaturation by high ionic strength. The respective effects of urea and salts on centrosomal structure and activity suggest that the centrosome is mainly held together by hydrogen and hydrophobic bonds. The in vitro microtubule nucleating activity of centrosomes can be inactivated at salt or urea concentrations that do not affect the parthenogenetic activity. Since egg cleavage requires the formation of microtubule asters, we conclude that the extracted or denatured microtubule nucleating activity of centrosomes can be complemented by components present in the egg cytoplasm. Both parthenogenetic and microtubule nucleating activities are abolished by protease treatments but resist nuclease action. Since we find no RNA in centrosomes treated by RNase, they probably do not contain a protected RNA. Taken together, these results are consistent with the idea that the whole or part of the centrosome structure acts as a seed to start the centrosome duplication cycle in Xenopus eggs.

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Hooghvorst, Isidre, and Salvador Nogués. "Opportunities and Challenges in Doubled Haploids and Haploid Inducer-Mediated Genome-Editing Systems in Cucurbits." Agronomy 10, no. 9 (September 22, 2020): 1441. http://dx.doi.org/10.3390/agronomy10091441.

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Doubled haploids have played a major role in cucurbit breeding for the past four decades. In situ parthenogenesis via irradiated pollen is the preferred technique to obtain haploid plantlets whose chromosomes are then doubled in Cucurbitaceae, such as melon, cucumber, pumpkin, squash and winter squash. In contrast to doubled haploid procedures in other species, in situ parthenogenesis in cucurbits presents many limiting factors which impede efficient production of haploids. In addition, it is very time-consuming and labor-intensive. However, the haploid inducer-mediated genome-editing system is a breakthrough technology for producing doubled haploids. Several reports have described using the CRISPR/Cas9 system in cucurbit species, and although its application has many bottlenecks, the targeted knock-out of the CENH3 gene will allow breeders to obtain haploid inducer lines that can be used to obtain parthenogenetic embryos. In this review, we discuss the progress made towards the development of doubled haploids and haploid inducer genotypes using CRISPR/Cas9 technologies in cucurbit species. The present review provides insights for the application of haploid inducer-mediated genome-editing system in cucurbit species

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Bloszyk, J., Z. Adamski, A. Napierala, and M. Dylewska. "Parthenogenesis as a life strategy among mites of the suborder Uropodina (Acari: Mesostigmata)." Canadian Journal of Zoology 82, no. 9 (September 1, 2004): 1503–11. http://dx.doi.org/10.1139/z04-133.

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This paper presents the results of observations concerning the phenomenon of parthenogenesis among European mites of the suborder Uropodina. An analysis of the sex ratios of 66 Polish species revealed that 18 of them (more than one fourth of the examined species) consisted only of females. The authors observed no significant relationship between geographical distribution and the lack of males in the population. Populations consisting entirely of females were observed among widely distributed species as well as among species characterized by narrow geographical ranges. Nonetheless, an increase in the number of parthenogenetic species, especially as a percentage of Middle European and Scandinavian fauna, was also discernible. Species that reproduced without males were associated with forest litter and soil, whereas bisexual species "eagerly" inhabited various relatively unstable and temporary micro environ ments (for instance, dead wood, birds' or small mammals' nests). The authors aim to define the biological role of occasionally appearing males for the species consisting almost entirely of females and discuss ecological and evolutionary aspects of parthenogenesis in mites of the suborder Uropodina.

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Di Ianni, Francesco, Sara Albarella, Alessandro Vetere, Marco Torcello, Michela Ablondi, Mariagiulia Pugliano, Susanna Di Mauro, Pietro Parma, and Francesca Ciotola. "Demonstration of Parthenogenetic Reproduction in a Pet Ball Python (Python regius) through Analysis of Early-Stage Embryos." Genes 14, no. 9 (August 31, 2023): 1744. http://dx.doi.org/10.3390/genes14091744.

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Parthenogenesis is an asexual form of reproduction, normally present in various animal and plant species, in which an embryo is generated from a single gamete. Currently, there are some species for which parthenogenesis is supposed but not confirmed, and the mechanisms that activate it are not well understood. A 10-year-old, wild-caught female ball python (Python regius) laid four eggs without any prior contact with a male. The eggs were not incubated and, after 3 days, were submitted to the University of Parma for analysis due to the suspicion of potential embryo presence. Examination of the egg content revealed residual blood vessels and a small red spot, indicative of an early-stage embryo. DNA was extracted from the three deceased embryos and from the mother’s blood, five microsatellites were analyzed to ascertain the origin of the embryos. The captive history data, together with the genetic microsatellite analysis approach, demonstrated the parthenogenetic origin of all three embryos. The embryos were homozygous for each of the maternal microsatellites, suggesting a terminal fusion automixis mode of development.

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Surani, M. Azim. "Parthenogenesis in man." Nature Genetics 11, no. 2 (October 1995): 111–13. http://dx.doi.org/10.1038/ng1095-111.

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KOIVISTO, R. K. KAROLIINA, and HENK R. BRAIG. "Microorganisms and parthenogenesis." Biological Journal of the Linnean Society 79, no. 1 (May 7, 2003): 43–58. http://dx.doi.org/10.1046/j.1095-8312.2003.00185.x.

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Jose de Carli, Gabriel, and Tiago Campos Pereira. "On human parthenogenesis." Medical Hypotheses 106 (September 2017): 57–60. http://dx.doi.org/10.1016/j.mehy.2017.07.008.

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Jourdane, J., D. Imbert-Establet, and L. A. Tchuem Tchuenté. "Parthenogenesis in Schistosomatidae." Parasitology Today 11, no. 11 (November 1995): 427–30. http://dx.doi.org/10.1016/0169-4758(95)80029-8.

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Moiseeva, E. M., V. V. Fadeev, Yu V. Krasova, and M. I. Chumakov. "Analysis of Mutations of the Maize Genes of Autonomous Embryo-, Endospermogenesis." Генетика 59, no. 9 (September 1, 2023): 1090–93. http://dx.doi.org/10.31857/s0016675823090084.

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The gynogenesis and parthenogenesis genes in Saratov maize lines was evaluated. In particular, the (Zm_Gex2, Zm_Gcs1, Zm_Pla1, Zm_CenH3, Zm_Dmp7) genes in haploid-inducing (ZMS-8, ZMSP) and (Zm_Chr106, Zm_Hdt104 and Zm_Fie1) genes in parthenogenetic (AT-1, AT-3, AT-4) and ordinary (KM, GPL-1) maize lines were sequenced. Using bioinformatic methods, gene sequences were compared in different maize lines and changes in nucleotide sequences were revealed. We suppose that it is possible to use Zm_Pla1, Zm_Gex2, and Zm_Fie1 genes for maize line genotyping.

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Kearney, Michael R., Moshe E. Jasper, Vanessa L. White, Ian J. Aitkenhead, Mark J. Blacket, Jacinta D. Kong, Steven L. Chown, and Ary A. Hoffmann. "Parthenogenesis without costs in a grasshopper with hybrid origins." Science 376, no. 6597 (June 3, 2022): 1110–14. http://dx.doi.org/10.1126/science.abm1072.

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The rarity of parthenogenetic species is typically attributed to the reduced genetic variability that accompanies the absence of sex, yet natural parthenogens can be surprisingly successful. Ecological success is often proposed to derive from hybridization through enhanced genetic diversity from repetitive origins or enhanced phenotypic breadth from heterosis. Here, we tested and rejected both hypotheses in a classic parthenogen, the diploid grasshopper Warramaba virgo . Genetic data revealed a single hybrid mating origin at least 0.25 million years ago, and comparative analyses of 14 physiological and life history traits showed no evidence for altered fitness relative to its sexual progenitors. Our findings imply that the rarity of parthenogenesis is due to constraints on origin rather than to rapid extinction.

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Journal articles on the topic 'Parthenogenesis'

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