Journal articles: 'Temperature-dependent sex determination'

1

Standora, Edward A., and James R. Spotila. "Temperature Dependent Sex Determination in Sea Turtles." Copeia 1985, no. 3 (August 5, 1985): 711. http://dx.doi.org/10.2307/1444765.

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TOKUNAGA, SHOJI. "Temperature-Dependent Sex Determination in Gekko japonicus (Gekkonidae, Reptilia). (temperature-dependent sex determination/Gekko japonicus/sex differentiation/Reptilia)." Development, Growth and Differentiation 27, no. 2 (April 1985): 117–20. http://dx.doi.org/10.1111/j.1440-169x.1985.00117.x.

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Robert, K. A., and M. B. Thompson. "Viviparity and Temperature-Dependent Sex Determination." Sexual Development 4, no. 1-2 (2010): 119–28. http://dx.doi.org/10.1159/000260373.

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Lang, Jeffrey W., and Harry V. Andrews. "Temperature-dependent sex determination in crocodilians." Journal of Experimental Zoology 270, no. 1 (September 15, 1994): 28–44. http://dx.doi.org/10.1002/jez.1402700105.

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Ferguson, Mark W. J., and Ted Joanen. "Temperature-dependent sex determination in Alligator mississippiensis." Journal of Zoology 200, no. 2 (August 20, 2009): 143–77. http://dx.doi.org/10.1111/j.1469-7998.1983.tb05781.x.

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Kallimanis, A. S. "Temperature dependent sex determination and climate change." Oikos 119, no. 1 (January 2010): 197–200. http://dx.doi.org/10.1111/j.1600-0706.2009.17674.x.

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Wibbels, Thane, James J. Bull, and David Crews. "Temperature-dependent sex determination: A mechanistic approach." Journal of Experimental Zoology 270, no. 1 (September 15, 1994): 71–78. http://dx.doi.org/10.1002/jez.1402700108.

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Mitchell, N. J., and F. J. Janzen. "Temperature-Dependent Sex Determination and Contemporary Climate Change." Sexual Development 4, no. 1-2 (2010): 129–40. http://dx.doi.org/10.1159/000282494.

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Georges, A., T. Ezaz, A. E. Quinn, and S. D. Sarre. "Are Reptiles Predisposed to Temperature- Dependent Sex Determination?" Sexual Development 4, no. 1-2 (2010): 7–15. http://dx.doi.org/10.1159/000279441.

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Janzen, F. J. "Is temperature-dependent sex determination in reptiles adaptive?" Trends in Ecology & Evolution 11, no. 6 (June 1996): 253. http://dx.doi.org/10.1016/0169-5347(96)91636-5.

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Wibbels, Thane, James J. Bull, and David Crews. "Chronology and morphology of temperature-dependent sex determination." Journal of Experimental Zoology 260, no. 3 (December 1991): 371–81. http://dx.doi.org/10.1002/jez.1402600311.

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Ewert, Michael A., Dale R. Jackson, and Craig E. Nelson. "Patterns of temperature-dependent sex determination in turtles." Journal of Experimental Zoology 270, no. 1 (September 15, 1994): 3–15. http://dx.doi.org/10.1002/jez.1402700103.

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Hays, Graeme C., Antonios D. Mazaris, Gail Schofield, and Jacques-Olivier Laloë. "Population viability at extreme sex-ratio skews produced by temperature-dependent sex determination." Proceedings of the Royal Society B: Biological Sciences 284, no. 1848 (February 8, 2017): 20162576. http://dx.doi.org/10.1098/rspb.2016.2576.

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For species with temperature-dependent sex determination (TSD) there is the fear that rising temperatures may lead to single-sex populations and population extinction. We show that for sea turtles, a major group exhibiting TSD, these concerns are currently unfounded but may become important under extreme climate warming scenarios. We show how highly female-biased sex ratios in developing eggs translate into much more balanced operational sex ratios so that adult male numbers in populations around the world are unlikely to be limiting. Rather than reducing population viability, female-biased offspring sex ratios may, to some extent, help population growth by increasing the number of breeding females and hence egg production. For rookeries across the world ( n = 75 sites for seven species), we show that extreme female-biased hatchling sex ratios do not compromise population size and are the norm, with a tendency for populations to maximize the number of female hatchlings. Only at extremely high incubation temperature does high mortality within developing clutches threaten sea turtles. Our work shows how TSD itself is a robust strategy up to a point, but eventually high mortality and female-only hatchling production will cause extinction if incubation conditions warm considerably in the future.

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Crews, David. "Temperature-Dependent Sex Determination: The Interplay of Steroid Hormones and Temperature." Zoological Science 13, no. 1 (February 1996): 1–13. http://dx.doi.org/10.2108/zsj.13.1.

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Alho, Cleber J. R., Tania M. S. Danni, and Luiz F. M. Padua. "Temperature-Dependent Sex Determination in Podocnemis expansa (Testudinata: Pelomedusidae)." Biotropica 17, no. 1 (March 1985): 75. http://dx.doi.org/10.2307/2388383.

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Godley, BJ, AC Broderick, F. Glen, and GC Hays. "Temperature-dependent sex determination of Ascension Island green turtles." Marine Ecology Progress Series 226 (2002): 115–24. http://dx.doi.org/10.3354/meps226115.

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Janzen, F. J. "Climate change and temperature-dependent sex determination in reptiles." Proceedings of the National Academy of Sciences 91, no. 16 (August 2, 1994): 7487–90. http://dx.doi.org/10.1073/pnas.91.16.7487.

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18

Pieau, C., M. Dorizzi, and N. Richard-Mercier. "Temperature-dependent sex determination and gonadal differentiation in reptiles." Cellular and Molecular Life Sciences 55, no. 7 (1999): 887. http://dx.doi.org/10.1007/s000180050342.

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Janes, Daniel E., Christopher L. Organ, Rami Stiglec, Denis O'Meally, Stephen D. Sarre, Arthur Georges, Jennifer A. M. Graves, et al. "Molecular evolution of Dmrt1 accompanies change of sex-determining mechanisms in reptilia." Biology Letters 10, no. 12 (December 2014): 20140809. http://dx.doi.org/10.1098/rsbl.2014.0809.

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In reptiles, sex-determining mechanisms have evolved repeatedly and reversibly between genotypic and temperature-dependent sex determination. The gene Dmrt1 directs male determination in chicken (and presumably other birds), and regulates sex differentiation in animals as distantly related as fruit flies, nematodes and humans. Here, we show a consistent molecular difference in Dmrt1 between reptiles with genotypic and temperature-dependent sex determination. Among 34 non-avian reptiles, a convergently evolved pair of amino acids encoded by sequence within exon 2 near the DM-binding domain of Dmrt1 distinguishes species with either type of sex determination. We suggest that this amino acid shift accompanied the evolution of genotypic sex determination from an ancestral condition of temperature-dependent sex determination at least three times among reptiles, as evident in turtles, birds and squamates. This novel hypothesis describes the evolution of sex-determining mechanisms as turnover events accompanied by one or two small mutations.

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Warner, Daniel A., and Richard Shine. "Interactions among thermal parameters determine offspring sex under temperature-dependent sex determination." Proceedings of the Royal Society B: Biological Sciences 278, no. 1703 (August 4, 2010): 256–65. http://dx.doi.org/10.1098/rspb.2010.1040.

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Bull, J. J. "Temperature-dependent sex determination in reptiles: validity of sex diagnosis in hatchling lizards." Canadian Journal of Zoology 65, no. 6 (June 1, 1987): 1421–24. http://dx.doi.org/10.1139/z87-224.

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In many reptiles, sex is determined by the incubation temperature of the egg. Studies of this phenomenon have usually diagnosed sex from gonads of hatchlings. The present study establishes the validity of this procedure in a lizard with temperature-dependent sex determination by diagnosing gonadal sex in hatchling leopard geckoes (Eublepharis macularius) and comparing these diagnoses with the sexes of the same animals as adults or subadults. The diagnosis of sex soon after hatching agreed with the subsequent diagnosis in all of the 96 animals studied. In a separate experiment, 29 eggs were divided between a male-producing and a female-producing treatment. Adult–subadult sex was significantly associated with temperature, indicating that temperature determined sex, and excluding for the first time the joint possibilities of differential mortality and (or) sex reversal after hatching. Previous fundamental assumptions about the nature of temperature-dependent sex determination in reptiles are consequently well established.

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Dong, Jinxiu, Lei Xiong, Hengwu Ding, Hui Jiang, Jiawei Zan, and Liuwang Nie. "Characterization of deoxyribonucleic methylation and transcript abundance of sex-related genes during tempera ture-dependent sex determination in Mauremys reevesii†." Biology of Reproduction 102, no. 1 (July 31, 2019): 27–37. http://dx.doi.org/10.1093/biolre/ioz147.

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Abstract A number of genes relevant for sex determination have been found in species with temperature-dependent sex determination. Epigenetics play a key role in sex determination, but characterization of deoxyribonucleic acid methylation of sex-related genes on temperature-dependent sex determination remains unclear. Mauremys reevesii is a typical species with temperature-dependent sex determination. In this study, we analyzed the Cytosine Guanine (CpG) methylation status of the proximal promoters, the messenger ribonucleic acid expression patterns and the correlation between methylation and expression levels of Aromatase, Forkhead box protein L2, Doublesex and mab3-related transcription factor 1, sex-determining region on Y chromosome-box 9, and anti-Müllerian hormone, which are key genes in sex determination in other species. We also analyzed the expression level of genes that encode enzymes involved in methylation and demethylation. The expression levels of Aromatase and Forkhead box protein L2 at the female producing temperature were higher than those at the male producing temperature; the expression levels of Doublesex and mab3-related transcription factor 1, sex-determining region on Y chromosome-box 9, and anti-Müllerian hormone were higher at MPT. The expression of some genes involved in methylation and demethylation is significantly different between male producing temperature and female producing temperature. The expression of messenger ribonucleic acid of genes involved in deoxyribonucleic acid methylation and demethylation affected by temperature, together with other factors, may change the methylation level of the regulatory regions of sex-related genes, which may further lead to temperature-specific expression of sex-related genes, and eventually affect the differentiation of the gonads.

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Merchant-Larios, Horacio, Verónica Díaz-Hernández, and Diego Cortez. "Molecular and Cellular Mechanisms Underlying Temperature-Dependent Sex Determination in Turtles." Sexual Development 15, no. 1-3 (2021): 38–46. http://dx.doi.org/10.1159/000515296.

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The discovery in mammals that fetal testes are required in order to develop the male phenotype inspired research efforts to elucidate the mechanisms underlying gonadal sex determination and differentiation in vertebrates. A pioneer work in 1966 that demonstrated the influence of incubation temperature on sexual phenotype in some reptilian species triggered great interest in the environment’s role as a modulator of plasticity in sex determination. Several chelonian species have been used as animal models to test hypotheses concerning the mechanisms involved in temperature-dependent sex determination (TSD). This brief review intends to outline the history of scientific efforts that corroborate our current understanding of the state-of-the-art in TSD using chelonian species as a reference.

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Lockwood, Samuel F., Brenden S. Holland, John W. Bickham, Brian G. Hanks, and James J. Bull. "Intraspecific genome size variation in a turtle (Trachemys scripta) exhibiting temperature-dependent sex determination." Canadian Journal of Zoology 69, no. 9 (September 1, 1991): 2306–10. http://dx.doi.org/10.1139/z91-324.

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Variation in genome size within and among populations of the pond slider, Trachemys scripta, a species with temperature-dependent sex determination, was investigated. Because genome size has been shown to affect developmental rate in various organisms, as does incubation temperature, it was hypothesized that genome size could influence sex determination in species with environmental sex determination. Significant variation in DNA content was found between geographic populations and among clutches. No significant differences in mean genome size were observed among samples incubated at different temperatures or between sexes of turtles hatched at a temperature that yields a mixed sex ratio. Thus, it appears that sex determination in T. scripta is accomplished in the absence of sex-specific and incubation-temperature-specific differences in genome size. Preliminary data from two populations, however, suggest that genome size may be significantly correlated with the threshold incubation temperature at which a mixed sex ratio is produced.

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25

Cornejo-Páramo, Paola, Duminda S. B. Dissanayake, Andrés Lira-Noriega, Mónica L. Martínez-Pacheco, Armando Acosta, Ciro Ramírez-Suástegui, Fausto R. Méndez-de-la-Cruz, et al. "Viviparous Reptile Regarded to Have Temperature-Dependent Sex Determination Has Old XY Chromosomes." Genome Biology and Evolution 12, no. 6 (May 20, 2020): 924–30. http://dx.doi.org/10.1093/gbe/evaa104.

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Abstract The water skinks Eulamprus tympanum and Eulamprus heatwolei show thermally induced sex determination where elevated temperatures give rise to male offspring. Paradoxically, Eulamprus species reproduce in temperatures of 12–15 °C making them outliers when compared with reptiles that use temperature as a cue for sex determination. Moreover, these two species are among the very few viviparous reptiles reported to have thermally induced sex determination. Thus, we tested whether these skinks possess undetected sex chromosomes with thermal override. We produced transcriptome and genome data for E. heatwolei. We found that E. heatwolei presents XY chromosomes that include 14 gametologs with regulatory functions. The Y chromosomal region is 79–116 Myr old and shared between water and spotted skinks. Our work provides clear evidence that climate could be useful to predict the type of sex determination systems in reptiles and it also indicates that viviparity is strictly associated with sex chromosomes.

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Yamaguchi, Toshiya, Norifumi Yoshinaga, Takashi Yazawa, Koichiro Gen, and Takeshi Kitano. "Cortisol Is Involved in Temperature-Dependent Sex Determination in the Japanese Flounder." Endocrinology 151, no. 8 (June 9, 2010): 3900–3908. http://dx.doi.org/10.1210/en.2010-0228.

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In vertebrates, sex is normally determined by genotype. However, in poikilothermal vertebrates, including reptiles, amphibians, and fishes, sex determination is greatly influenced by environmental factors, such as temperature. Little is known about the molecular mechanisms underlying environmental sex determination in these species. The Japanese flounder (Paralichthys olivaceus) is a teleost fish with an XX/XY sex determination system. However, XX flounder can be induced to develop into predominantly either phenotypic females or males, by rearing at 18 or 27 C, respectively, during the sex differentiation period. Therefore, the flounder provides an excellent model to study the molecular mechanisms underlying temperature-dependent sex determination. We previously showed that an aromatase inhibitor, an antiestrogen, and 27 C treatments cause masculinization of XX flounder, as well as suppression of mRNA expression of ovary-type aromatase (cyp19a1), a steroidogenic enzyme responsible for the conversion of androgens to estrogens in the gonads. Furthermore, estrogen administration completely inhibits masculinization by these treatments, suggesting suppression of cyp19a1 mRNA expression, and the resultant estrogen biosynthesis may trigger masculinization of the XX flounder induced by high water temperature. Here, we demonstrated that cortisol causes female-to-male sex reversal by directly suppressing cyp19a1 mRNA expression via interference with cAMP-mediated activation and that metyrapone (an inhibitor of cortisol synthesis) inhibits 27 C-induced masculinization of XX flounder. Moreover, cortisol concentrations in 27 C-reared juveniles were significantly higher than in 18 C-reared fishes during sexual differentiation. These results strongly suggest that masculinization by high water temperature is ascribable to elevation of cortisol concentration during gonadal sex differentiation in the flounder.

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Bull, J. J., John M. Legler, and R. C. Vogt. "Non-Temperature Dependent Sex Determination in Two Suborders of Turtles." Copeia 1985, no. 3 (August 5, 1985): 784. http://dx.doi.org/10.2307/1444773.

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28

Rhen, T., A. Schroeder, J. T. Sakata, V. Huang, and D. Crews. "Segregating variation for temperature-dependent sex determination in a lizard." Heredity 106, no. 4 (August 11, 2010): 649–60. http://dx.doi.org/10.1038/hdy.2010.102.

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29

Grossen, Christine, Samuel Neuenschwander, and Nicolas Perrin. "TEMPERATURE-DEPENDENT TURNOVERS IN SEX-DETERMINATION MECHANISMS: A QUANTITATIVE MODEL." Evolution 65, no. 1 (September 24, 2010): 64–78. http://dx.doi.org/10.1111/j.1558-5646.2010.01098.x.

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Western, Patrick S., Jenny L. Harry, Jennifer A. Marshall Graves, and Andrew H. Sinclair. "Temperature-dependent sex determination in the american alligator:AMH precedesSOX9 expression." Developmental Dynamics 216, no. 4/5 (December 1999): 411–19. http://dx.doi.org/10.1002/(sici)1097-0177(199912)216:4/5<411::aid-dvdy9>3.0.co;2-y.

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Viets, Brian E., Alan Tousignant, Michael A. Ewert, Craig E. Nelson, and David Crews. "Temperature-dependent sex determination in the leopard gecko,Eublepharis macularius." Journal of Experimental Zoology 265, no. 6 (May 1, 1993): 679–83. http://dx.doi.org/10.1002/jez.1402650610.

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Smith, Craig A., and Jean M. P. Joss. "Gonadal sex differentiation in Alligator mississippiensis, a species with temperature-dependent sex determination." Cell and Tissue Research 273, no. 1 (July 1993): 149–62. http://dx.doi.org/10.1007/bf00304622.

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ALLSOP, D. J., D. A. WARNER, T. LANGKILDE, W. DU, and R. SHINE. "Do operational sex ratios influence sex allocation in viviparous lizards with temperature-dependent sex determination?" Journal of Evolutionary Biology 19, no. 4 (July 2006): 1175–82. http://dx.doi.org/10.1111/j.1420-9101.2006.01086.x.

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Whiteley, Sarah L., Arthur Georges, Vera Weisbecker, Lisa E. Schwanz, and Clare E. Holleley. "Ovotestes suggest cryptic genetic influence in a reptile model for temperature-dependent sex determination." Proceedings of the Royal Society B: Biological Sciences 288, no. 1943 (January 20, 2021): 20202819. http://dx.doi.org/10.1098/rspb.2020.2819.

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Sex determination and differentiation in reptiles is complex. Temperature-dependent sex determination (TSD), genetic sex determination (GSD) and the interaction of both environmental and genetic cues (sex reversal) can drive the development of sexual phenotypes. The jacky dragon ( Amphibolurus muricatus ) is an attractive model species for the study of gene–environment interactions because it displays a form of Type II TSD, where female-biased sex ratios are observed at extreme incubation temperatures and approximately 50 : 50 sex ratios occur at intermediate temperatures. This response to temperature has been proposed to occur due to underlying sex determining loci, the influence of which is overridden at extreme temperatures. Thus, sex reversal at extreme temperatures is predicted to produce the female-biased sex ratios observed in A. muricatus . The occurrence of ovotestes during development is a cellular marker of temperature sex reversal in a closely related species Pogona vitticeps . Here, we present the first developmental data for A. muricatus , and show that ovotestes occur at frequencies consistent with a mode of sex determination that is intermediate between GSD and TSD. This is the first evidence suggestive of underlying unidentified sex determining loci in a species that has long been used as a model for TSD.

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Crews, D., A. R. Cantú, and J. M. Bergeron. "Temperature and non-aromatizable androgens: a common pathway in male sex determination in a turtle with temperature-dependent sex determination?" Journal of Endocrinology 149, no. 3 (June 1996): 457–63. http://dx.doi.org/10.1677/joe.0.1490457.

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Abstract This study addressed the hypothesis that, in the red-eared slider turtle, Trachemys scripta, non-aromatizable androgens are the physiological equivalent of temperature in determining male development. In the first experiment, eggs were treated in the middle of the temperature-sensitive period with 1·0 or 10·0 μg androsterone, 5α-dihydrotestosterone, 3α-androstanediol, or 3β-androstanediol, while at an all-male, male-biased, or one of two female-biased incubation temperatures. In the second experiment, eggs were treated with the same dosages of dihydrotestosterone at different stages of embryonic development while at a male-biased, threshold, or a female-biased incubation temperature. Results of experiment one indicated that hormone-induced masculinization is specific to non-aromatizable androgens. Results of experiment two indicated that the sensitivity to dihydrotestosterone corresponds to the temperature-sensitive window during development. Further, there is a dose–response relationship but no apparent synergism between exogenous dihydrotestosterone and incubation temperature. When considered with other research, it is suggested that non-aromatizable androgens and their products are involved in the initiation of male sex determination whereas oestrogens and their aromatizable androgen precursors are involved in the initiation of female sex determination. Journal of Endocrinology (1996) 149, 457–463

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Conover, D. O., and S. B. DeMond. "Absence of temperature-dependent sex determination in northern populations of two cyprinodontid fishes." Canadian Journal of Zoology 69, no. 2 (February 1, 1991): 530–33. http://dx.doi.org/10.1139/z91-080.

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We tested for an effect of temperature during embryonic and larval development on the sex ratio of offspring in two cyprinodontid fishes (Fundulus heteroclitus and Cyprinodon variegatus) having life histories in which temperature-dependent sex determination might be expected to occur. In both species, field collections showed that as young of the year recruited to the population, the sex ratio did not vary over time, nor did it deviate from 1:1. In laboratory experiments, there was no influence of incubation temperature on sex ratio in either species and sex ratios were near unity in all treatments. Although there was no evidence of temperature-dependent sex determination in the populations we studied, this result should be confirmed on other populations before it is generalized to the species level.

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Robert, Kylie A., Michael B. Thompson, and Frank Seebacher. "Facultative sex allocation in the viviparous lizard Eulamprus tympanum, a species with temperature-dependent sex determination." Australian Journal of Zoology 51, no. 4 (2003): 367. http://dx.doi.org/10.1071/zo03016.

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Females of the Australian scincid lizard Eulamprus tympanum can manipulate the sex of their offspring in response to gender imbalances in the population using temperature-dependent sex determination. Here we show that when adult males are scarce females produced male-biased litters and when adult males were common females produced female-biased litters. The cues used by a female to assess the adult population are not known but presumably depend upon her experience throughout the breeding season. Maternal manipulation of the sex ratio of the offspring in E. tympanum illustrates a selective advantage of temperature-dependent sex determination in a viviparous species.

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Herrera, Candy, Evelyn Guerra, Andrea Rosas, Yingying Wei, Jack Pringle, Baltazar Espinoza, and Baojun Song. "The Impact of Temperature-Dependent Sex Determination on the Population Dynamics of Green Sea Turtles (Chelonia mydas)." Bionatura 5, no. 1 (February 15, 2020): 1029–38. http://dx.doi.org/10.21931/rb/2020.05.01.4.

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The sex of the turtles is determined by the incubation temperature of the eggs during the mid-trimester of development. In green sea turtles (Chelonia mydas), recent studies show that sex ratios are changing, producing a female-biased sex ratio within the population. We developed a novel continuous model to analyze the dynamics of the green sea turtle population long-term. We determine the safe operating space for the proportion of eggs that become male at which the population of green sea turtle can exist without going to extinction. When the proportion of male eggs leaves this range the overall turtles’ population collapses. Additionally, we examined how temperature changes affect the sex ratios of the green sea turtle population.

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Sun, Bao-Jun, Teng Li, Yi Mu, Jessica K. McGlashan, Arthur Georges, Richard Shine, and Wei-Guo Du. "Thyroid hormone modulates offspring sex ratio in a turtle with temperature-dependent sex determination." Proceedings of the Royal Society B: Biological Sciences 283, no. 1841 (October 26, 2016): 20161206. http://dx.doi.org/10.1098/rspb.2016.1206.

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The adaptive significance of temperature-dependent sex determination (TSD) has attracted a great deal of research, but the underlying mechanisms by which temperature determines the sex of a developing embryo remain poorly understood. Here, we manipulated the level of a thyroid hormone (TH), triiodothyronine (T 3 ), during embryonic development (by adding excess T 3 to the eggs of the red-eared slider turtle Trachemys scripta , a reptile with TSD), to test two competing hypotheses on the proximate basis for TSD: the developmental rate hypothesis versus the hormone hypothesis . Exogenous TH accelerated embryonic heart rate (and hence metabolic rate), developmental rate, and rates of early post-hatching growth. More importantly, hyperthyroid conditions depressed expression of Cyp19a1 (the gene encoding for aromatase) and levels of oestradiol, and induced more male offspring. This result is contrary to the direction of sex-ratio shift predicted by the developmental rate hypothesis , but consistent with that predicted by the hormone hypothesis . Our results suggest an important role for THs in regulating sex steroid hormones, and therefore, in affecting gonadal sex differentiation in TSD reptiles. Our study has implications for the conservation of TSD reptiles in the context of global change because environmental contaminants may disrupt the activity of THs, and thereby affect offspring sex in TSD reptiles.

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Pezaro, N., M. B. Thompson, and J. S. Doody. "Seasonal sex ratios and the evolution of temperature-dependent sex determination in oviparous lizards." Evolutionary Ecology 30, no. 3 (January 23, 2016): 551–65. http://dx.doi.org/10.1007/s10682-016-9820-0.

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Shen, Zhi-Gang, and Han-Ping Wang. "Molecular players involved in temperature-dependent sex determination and sex differentiation in Teleost fish." Genetics Selection Evolution 46, no. 1 (2014): 26. http://dx.doi.org/10.1186/1297-9686-46-26.

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Massey, Melanie D., Sarah M. Holt, Ronald J. Brooks, and Njal Rollinson. "Measurement and modelling of primary sex ratios for species with temperature-dependent sex determination." Journal of Experimental Biology 222, no. 1 (October 23, 2018): jeb190215. http://dx.doi.org/10.1242/jeb.190215.

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Pieau, C., and M. Dorizzi. "Oestrogens and temperature-dependent sex determination in reptiles: all is in the gonads." Journal of Endocrinology 181, no. 3 (June 1, 2004): 367–77. http://dx.doi.org/10.1677/joe.0.1810367.

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In many species of oviparous reptiles, the first steps of gonadal sex differentiation depend on the incubation temperature of the eggs. Feminization of gonads by exogenous oestrogens at a male-producing temperature and masculinization of gonads by antioestrogens and aromatase inhibitors at a female-producing temperature have irrefutably demonstrated the involvement of oestrogens in ovarian differentiation. Nevertheless, several studies performed on the entire gonad/adrenal/mesonephros complex failed to find differences between male- and female-producing temperatures in oestrogen content, aromatase activity and aromatase gene expression during the thermosensitive period for sex determination. Thus, the key role of aromatase and oestrogens in the first steps of ovarian differentiation has been questioned, and extragonadal organs or tissues, such as adrenal, mesonephros, brain or yolk, were considered as possible targets of temperature and sources of the oestrogens acting on gonadal sex differentiation.In disagreement with this view, experiments and assays carried out on the gonads alone, i.e. separated from the adrenal/mesonephros, provide evidence that the gonads themselves respond to temperature shifts by modifying their sexual differentiation and are the site of aromatase activity and oestrogen synthesis during the thermosensitive period. Oestrogens act locally on both the cortical and the medullary part of the gonad to direct ovarian differentiation. We have concluded that there is no objective reason to search for the implication of other organs in the phenomenon of temperature-dependent sex determination in reptiles. From the comparison with data obtained in other vertebrates, we propose two main directions for future research: to examine how transcription of the aromatase gene is regulated and to identify molecular and cellular targets of oestrogens in gonads during sex differentiation, in species with strict genotypic sex determination and species with temperature-dependent sex determination.

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Weber, Ceri, Yingjie Zhou, Jong Gwan Lee, Loren L. Looger, Guoying Qian, Chutian Ge, and Blanche Capel. "Temperature-dependent sex determination is mediated by pSTAT3 repression of Kdm6b." Science 368, no. 6488 (April 16, 2020): 303–6. http://dx.doi.org/10.1126/science.aaz4165.

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In many reptiles, including the red-eared slider turtle Trachemys scripta elegans (T. scripta), sex is determined by ambient temperature during embryogenesis. We previously showed that the epigenetic regulator Kdm6b is elevated at the male-producing temperature and essential to activate the male pathway. In this work, we established a causal link between temperature and transcriptional regulation of Kdm6b. We show that signal transducer and activator of transcription 3 (STAT3) is phosphorylated at the warmer, female-producing temperature, binds the Kdm6b locus, and represses Kdm6b transcription, blocking the male pathway. Influx of Ca2+, a mediator of STAT3 phosphorylation, is elevated at the female temperature and acts as a temperature-sensitive regulator of STAT3 activation.

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Wibbels, Thane, Flavius C. Killebrew, and David Crews. "Sex determination in Cagle's map turtle: implications for evolution, development, and conservation." Canadian Journal of Zoology 69, no. 10 (October 1, 1991): 2693–96. http://dx.doi.org/10.1139/z91-378.

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Sex determination was investigated in Cagle's map turtle, Graptemys caglei, which has a restricted distribution which is the southernmost of all Graptemys species. This species exhibits temperature-dependent sex determination, with high incubation temperatures producing only females and low temperatures producing only males. The estimated pivotal temperature (approximately 30.0 °C) is higher than those reported for other species of Graptemys in North America; however, the interspecific variations in pivotal temperature are small (approximately 0.5–1.0 °C). Temperature appears to affect the ovarian or testicular nature of the gonads in an "all or none" fashion, but exerts a graded effect on the length of ovaries. In addition, temperature appears to exert a graded effect on the regression of the oviducts in males. The occurrence of temperature-dependent sex determination in this species is also of conservational importance, since alterations to a single river system could potentially impact the reproductive success of this species by changing nest temperatures and, thus, population sex ratio(s).

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LeBlanc, AM, T. Wibbels, D. Shaver, and JS Walker. "Temperature-dependent sex determination in the Kemp’s ridley sea turtle: effects of incubation temperatures on sex ratios." Endangered Species Research 19, no. 2 (December 13, 2012): 123–28. http://dx.doi.org/10.3354/esr00465.

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Burke, Russell L., and Arthur M. Calichio. "Temperature-Dependent Sex Determination in the Diamond-backed Terrapin (Malaclemys terrapin)." Journal of Herpetology 48, no. 4 (December 2014): 466–70. http://dx.doi.org/10.1670/13-188.

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Janzen, Frederic J. "Experimental Evidence for the Evolutionary Significance of Temperature Dependent Sex Determination." Evolution 49, no. 5 (October 1995): 864. http://dx.doi.org/10.2307/2410409.

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Escobedo-Galván, Armando H. "Temperature-dependent sex determination in an uncertain world: advances and perspectives." Revista Mexicana de Biodiversidad 84, no. 2 (June 2013): 727–30. http://dx.doi.org/10.7550/rmb.32441.

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DEEMING, DENIS C., and MARK W. J. FERGUSON. "The Mechanism of Temperature Dependent Sex Determination in Crocodilians: A Hypothesis." American Zoologist 29, no. 3 (August 1989): 973–85. http://dx.doi.org/10.1093/icb/29.3.973.

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Journal articles on the topic 'Temperature-dependent sex determination'

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