Journal articles: 'Macropus eugenii Spermatozoa'

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SETIADI, DADI, MINJIE LIN, and JOHN C. RODGER. "Posttesticular development of spermatozoa of the tammar wallaby (Macropus eugenii)." Journal of Anatomy 190, no. 2 (February 1997): 275–88. http://dx.doi.org/10.1046/j.1469-7580.1997.19020275.x.

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Sistina, Yulia, Minjie Lin, and John C. Rodger. "Lysophosphatidylcholine disrupts the acrosome of tammar wallaby (macropus eugenii) spermatozoa." Molecular Reproduction and Development 35, no. 3 (July 1993): 277–84. http://dx.doi.org/10.1002/mrd.1080350310.

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Bennetts, Liga, Minjie Lin, and R. John Aitken. "Cyclic AMP-dependent tyrosine phosphorylation in tammar wallaby (Macropus eugenii) spermatozoa." Journal of Experimental Zoology 301A, no. 2 (2004): 118–30. http://dx.doi.org/10.1002/jez.a.20020.

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Molinia, FC, and JC Rodger. "Pellet-freezing spermatozoa of two marsupials: the tammar wallaby, Macropus eugenii, and the brushtail possum, Trichosurus vulpecula." Reproduction, Fertility and Development 8, no. 4 (1996): 681. http://dx.doi.org/10.1071/rd9960681.

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A protocol was developed for pellet-freezing spermatozoa of the tammar wallaby and the brushtail possum. Seren was collected by electro-ejaculation and wallaby spermatozoa were washed by 'swim-up' into phosphate-buffered saline (PBS), whereas possum spermatozoa were not washed. Wallaby spermatozoa were screened for toxicity in diluents containing a range of cryoprotectants (0-10%): dimethyl sulfoxide (DMSO), ethylene glycol and propanediol. Possum spermatozoa were tolerant of diluents containing 17.5% glycerol. Wallaby and possum spermatozoa were diluted 1:1 with the most promising cryoprotective diluents (final concentrations in PBS: possum, 17.5% glycerol; wallaby, 7.5% glycerol + 10% DMSO) and, after 5 min equilibration at room temperature, were pellet-frozen. Pellets were thawed (35 degrees C) and wallaby spermatozoa were washed by centrifugation (200 g for 5 min) and resuspended in PBS to minimize cryoprotectant toxicity. A high proportion of possum spermatozoa was recovered after freezing (67.5%), having good progressive motility (3.6 on a 0-5 scale). The progressive motility of frozen-thawed wallaby spermatozoa was also high (3.0), but only 10% of motile spermatozoa were recovered. The pellet-freezing method in conjunction with the post-thaw washing procedure (wallaby) may produce a viable population of cryopreserved marsupial spermatozoa suitable for use in assisted-breeding techniques such as in vitro fertilization and artificial insemination.

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Chaturapanich, G., RC Jones, and J. Clulow. "Protein synthesis and secretion by the epididymis of the tammar wallaby, Macropus eugenii (Macropodidae: Marsupialia)." Reproduction, Fertility and Development 4, no. 5 (1992): 533. http://dx.doi.org/10.1071/rd9920533.

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The objectives were to assess the following in a marsupial: which proteins are synthesized by the different regions of the epididymis and secreted into the lumen of the ductus; the effect of the experimental method on the detection of protein secretion; the role of the testis in regulating the protein synthesis and secretion; and whether any of the secreted proteins may associate with spermatozoa. Samples from untreated animals were collected for examination by perfusing Krebs-bicarbonate through the ductus epididymidis in vivo (microperfusion), and after incorporation of [35S]methionine during incubation of minced duct in vitro. Electrophoresis of the samples showed that the caput and corpus epididymidis (initial segments) secreted most of the proteins that were synthesized and secreted by the epididymal mucosa, and that the cauda epididymidis secreted mainly blood proteins. Also, many more proteins were secreted in vitro than into the microperfusates in vivo, or were found by Jones (1987) in micropuncture samples of epididymal plasma. The synthesis and secretion of five proteins was androgen dependent (M(r) 75,700, 30,000, 18,700, 17,400 and 12,800). Also, the luminal fluids from the testis stimulated the secretion of two proteins (M(r) 46,300 and 36,100) and inhibited the secretion of three proteins (M(r) 43,000, 32,300 and 21,400). Examination of detergent extracts of spermatozoa indicated that they lose three proteins (M(r) 28,000, 30,000 and 47,000) and gain one (M(r) 30,400) during passage through the epididymis. The method of determining protein secretion affected the findings. Protein secretion, its control and its association with spermatozoa are broadly similar in the tammar wallaby to the processes described in eutherian mammals.

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Chaturapanich, G., R. C. Jones, and J. Clulow. "Role of androgens in survival of spermatozoa in epididymis of tammar wallaby (Macropus eugenii)." Reproduction 95, no. 2 (July 1, 1992): 421–29. http://dx.doi.org/10.1530/jrf.0.0950421.

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Murdoch, R. N., and R. C. Jones. "The metabolic properties of spermatozoa from the epididymis of the tammar wallaby,Macropus eugenii." Molecular Reproduction and Development 49, no. 1 (January 1998): 92–99. http://dx.doi.org/10.1002/(sici)1098-2795(199801)49:1<92::aid-mrd10>3.0.co;2-4.

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Paris, Damien B. B. P., David A. Taggart, Monica C. J. Paris, Peter D. Temple-Smith, and Marilyn B. Renfree. "Sperm transport, size of the seminal plug and the timing of ovulation after natural mating in the female tammar wallaby Macropus eugenii." Reproduction, Fertility and Development 16, no. 8 (2004): 811. http://dx.doi.org/10.1071/rd04089.

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The distribution of spermatozoa and seminal plug in the reproductive tract and the timing of ovulation were examined at various times in a naturally mated monovular macropodid marsupial, namely the tammar wallaby (Macropus eugenii). After the first post partum (p.p.) mating, 28 females were isolated and their reproductive tracts dissected at 0.5, 6, 18, 36 and 40 h post coitum (p.c.). Each tract was ligated into 13 major anatomical sections and spermatozoa and eggs were recovered by flushing. Mating was possibly delayed by handling and occurred 21.7 ± 2.5 h p.p. in these animals. Copulation lasted 7.8 ± 0.7 min. Within 0.5 h after a single mating, the tract contained 25.8 ± 10.2 × 106 spermatozoa and 21.6 ± 8.8 g of seminal plug, 96% and 70% of which was lost within 6 h p.c. respectively. Spermatozoa reached the uterus, isthmus and ampulla of the oviduct on the side of the developing follicle within 0.5, 6 and 18 h p.c., respectively, and a uterine population of 26.1 ± 12.103 spermatozoa was maintained for over 40 h. Sperm numbers were reduced at the cervix (up to 57-fold) and uterotubule junction (eight-fold) and only one in approximately 7500 ejaculated spermatozoa (3.4 ± 0.9 × 103) reached the oviduct on the follicle side. Differential transport of spermatozoa was not observed. Although the numbers of spermatozoa were reduced in the parturient uterus, they were highly variable and were not significantly different to those in the non-parturient uterus. Ovulation and recovery of sperm-covered eggs from the isthmus occurred 36–41 h p.c. (49–72 h p.p.). In contrast with the polyovular dasyurid and didelphid marsupials, the tammar wallaby ejaculates large numbers of spermatozoa, but transport is relatively inefficient and sperm storage in the tract before ovulation is limited.

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Czarny, N. A., K. E. Mate, and J. C. Rodger. "Acrosome stability in the spermatozoa of dasyurid marsupials." Reproduction, Fertility and Development 20, no. 2 (2008): 295. http://dx.doi.org/10.1071/rd07178.

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The spermatozoa of most marsupials lack nuclear stabilising disulfide-bonded protamines found in eutherian mammals. However, disulfide stabilisation has been observed in the acrosome of macropodid (Macropus eugenii) and phalangerid (Trichosurus vulpecula) marsupials. As a result this organelle, which is normally fragile in eutherian mammals, is robust and able to withstand physical and chemical challenge in these marsupials. The present study examined acrosomal characteristics of the spermatozoa of three dasyurid marsupials; the fat-tailed dunnart (Sminthopsis crassicaudata), eastern quoll (Dasyurus viverrinus) and northern quoll (Dasyurus hallucatus). In all species examined Bryan’s staining demonstrated that significant acrosomal loss occurred following physical challenge with osmotic stress, cryopreservation without cryoprotectant and exposure to detergent (Triton-X). Bromobimane staining indicated that the acrosomes of dasyurids lacked stabilising disulfide bonds. As reported for the wallaby and possum, calcium ionophore (A23187) did not induce the acrosome reaction-like exocytosis in dasyurid spermatozoa but treatment with diacylglycerol (DiC8) caused significant acrosome loss at concentrations similar to those effective for other marsupials. The present study found that the spermatozoa of dasyurids are more sensitive to physical challenge than the previously-studied marsupials and we suggest that this is due to the absence of acrosomal stabilising disulfide bonds.

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Renfree, MB, and AM Lewis. "Cleavage in vivo and in vitro in the Marsupial Macropus eugenii." Reproduction, Fertility and Development 8, no. 4 (1996): 725. http://dx.doi.org/10.1071/rd9960725.

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In the tammar wallaby, transport down the oviduct takes less than 24 h after fertilization and a mucoid coat is deposited within a few hours of fertilization, with excess spermatozoa trapped in the mucoid layer. The mucin coat thickens as the zygote passes down the oviduct. A proteinaceous shell is laid down outside the mucin coat in the utero-tubal region of the tract. The fertilized zygote enters the uterus in the pronuclear stage with cleavage proceeding in the uterus. In vivo, the first cleavage takes place two days post coitum (p.c.) (approximately 24 h after ovulation) but the next three cleavage stages may be completed within 24 h (between 48 h and 72 h p.c.). Thus, cell-doubling time appears to be around 8 h for 2-8-cell stages. Cleavage in vitro can occur with, or without, the shell membrane. Cleavage in early embryos of the tammar in vitro is slower than that occurring in vivo, and in vitro there may be a '4-cell block' in early development, as in dasyurids. The pattern of cleavage differs markedly from that of dasyurid marsupials in that there is no extrusion of yolk material from the cells and no separation of the blastomeres during the first cleavage stages to the 8-cell stage. The blastomeres are characterized by numerous vesicular structures and lipid droplets, but no yolk bodies. Polarity is not marked in early cleavage, but by the 8-cell stage polarity has developed with surface microvilli and numerous granular vesicles and mitochondria in the cortical regions at one pole of the cells, but sparse microvilli on the inner surfaces and at the other pole. There are complex intervillous interdigitations of microvilli between cells. However, clear identification of cells as pluriblast or trophoblast cells is not possible up to the 8-cell stage examined. These results demonstrate that this macropodid marsupial has a distinctive pattern of early development which differs from that of Didelphis and of the dasyurid marsupials so far described.

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Chaturapanich, G., and RC Jones. "Morphometry of the epididymis of the tammar wallaby, Macropus eugenii, and estimation of some physiological parameters." Reproduction, Fertility and Development 3, no. 6 (1991): 651. http://dx.doi.org/10.1071/rd9910651.

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About 14 ductuli efferentes (mean length 48 cm) leave the testis of the tammar. The caput, corpus and cauda epididymidis constitute 37%, 42% and 21% respectively of the total length of the ductus epididymidis (estimated to be 34.9 m long). The initial segments of the ductus epididymidis are longer, relative to body or testis mass, in the tammar than in eutherian mammals such as the rat. The main morphometric features of the male excurrent duct system of the tammar are a high ratio of surface area of luminal border:luminal volume of the ductuli efferentes (which reabsorb most of the fluid leaving the testis), a high ratio of epithelial volume:luminal volume in the caput and corpus epididymidis (which are involved in sperm maturation) and a low ratio of epithelial volume:luminal volume in the cauda epididymidis (which is involved in sperm storage). Estimates of fluid reabsorption by the ductuli efferentes and protein secretion by the caput epididymidis were respectively 8.9 microL cm-2h-1 and 2.8 micrograms cm-2h-1. Other estimates for the ductuli efferentes, caput, corpus and cauda epididymidis respectively were: sperm velocity (4.5, 4.8, 2.2, and 0.9 mm min-1), duration of sperm transit (107 min, 1.9 days, 4.7 days, and 6.3 days), total number of spermatozoa (4950 x 10(6)) and distribution of extragonadal spermatozoa (0.6, 14, 36 and 49% of the total). The values are within the ranges estimated for eutherian mammals.

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LIN, MINJIE, and JOHN C. RODGER. "Acrosome formation during sperm transit through the epididymis in two marsupials, the tammar wallaby (Macropus eugenii) and the brushtail possum (Trichosurus vulpecula)." Journal of Anatomy 194, no. 2 (February 1999): 223–32. http://dx.doi.org/10.1017/s0021878299004586.

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In certain Australian marsupials including the tammar wallaby (Macropus eugenii) and the brushtail possum (Trichosurus vulpecula), formation of the acrosome is not completed in the testis but during a complex differentiation process as spermatozoa pass through the epididymis. Using transmission and scanning electron microscopy this paper defined the process of acrosome formation in the epididymis, providing temporal and spatial information on the striking reorganisation of the acrosomal membranes and matrix and of the overlying sperm surface involved. On leaving the testis wallaby and possum spermatozoa had elongated ‘scoop’-shaped acrosomes projecting from the dorsal surface of the head. During passage down the epididymis, this structure condensed into the compact button-like organelle found on ejaculated spermatozoa. This condensation was achieved by a complex process of infolding and fusion of the lateral projections of the ‘scoop’. In the head of the epididymis the rims of the lateral scoop projections became shorter and thickened and folded inwards, to eventually meet midway along the longitudinal axis of the acrosome. As spermatozoa passed through the body of the epididymis the lateral projections fused together. Evidence of this fusion of the immature outer acrosomal membrane is the presence of vesicles within the acrosomal matrix which persist even in ejaculated spermatozoa. When spermatozoa have reached the tail of the epididymis the acrosome condenses into its mature form, as a small button-like structure contained within the depression on the anterior end of the nucleus. During the infolding process, the membranes associated with the immature acrosome are either engulfed into the acrosomal matrix (outer acrosomal membrane), or eliminated from the sperm head as tubular membrane elements (cytoplasmic membrane). Thus the surface and organelles of the testicular sperm head are transient structures in those marsupials with posttesticular acrosome formation and this must be taken into consideration in attempts to dissect the cell and molecular biology of fertilisation.

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Paris, D. B. B. P., D. A. Taggart, M. C. J. Paris, P. D. Temple-Smith, and M. B. Renfree. "198 DISTRIBUTION OF SPERMATOZOA AND COPULATORY PLUG IN RELATION TO THE TIME OF MATING AND OVULATION IN THE FEMALE TAMMAR WALLABY (MACROPUS EUGENII)." Reproduction, Fertility and Development 17, no. 2 (2005): 249. http://dx.doi.org/10.1071/rdv17n2ab198.

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In the monovular macropodid marsupial, the tammar wallaby (Macropus eugenii), the cervices are the primary selective barrier to spermatozoa, resulting in differential transport to the non-gravid uterus where a sperm reservoir is established (Tyndale-Biscoe CH and Rodger JC 1978 J. Reprod. Fertil. 52, 37–43). However, due to limited sample size, the dynamics of sperm transport could not be thoroughly examined. In this study, the distribution of spermatozoa, the size of the copulatory plug in the reproductive tract at various times after mating, and the timing of ovulation were characterized in 28 naturally mated female tammars. After the first postpartum (p.p.) mating, adult females were isolated and their reproductive tracts dissected at 0.5, 6, 18, 36, and 40 h post-coitum (p.c.). Each tract was ligated into 13 major anatomical sections, and spermatozoa and eggs were recovered by flushing. Mating occurred 21.7 ± 2.5 h p.p. (mean ± SEM; n = 20) in these animals that were checked frequently and lasted 7.8 ± 0.7 min (n = 15). Within 0.5 h after a single mating (n = 5) the tract contained 2.6 ± 1.0 × 107 spermatozoa and 21.6 ± 8.8 g of copulatory plug, 96 and 70% of which was lost within 6 h p.c., respectively. Spermatozoa reached the uterus, isthmus, and ampulla of the oviduct ipsilateral to the developing follicle within 0.5, 6, and 18 h p.c. respectively, and a uterine population of 2.6 ± 1.2 × 104 spermatozoa (n = 24) was maintained for over 40 h (ANOVA, P > 0.05). Sperm numbers were reduced at the cervix (up to 57-fold) and utero-tubule junction (8-fold), and only 1 in ∼7600 ejaculated spermatozoa (3.4 ± 0.9 × 103; n = 14) reached the oviduct on the side of ovulation. Although sperm numbers were reduced in the gravid uterus (n = 24), differential transport of spermatozoa was not observed (ANOVA, P > 0.05). Ovulation and recovery of sperm-covered eggs from the isthmus of the oviduct occurred 36–41 h p.c. (49–72 h p.p.) (n = 8). Like many eutherian mammals, but in contrast to polyovular dasyurid and didelphid marsupials, the tammar ejaculates large numbers of spermatozoa, but transport is relatively inefficient and sperm storage in the tract before ovulation is limited. Research was supported by the Australian Research Council (grant No. C09930004) and the University of Melbourne.

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Lin, M., X. Zhang, M. Wade, M. Harris, and M. Nickel. "Isolation of proteins from subacrosomal region of spermatozoa from a marsupial, the tammar wallaby (Macropus eugenii)." Reproduction 113, no. 2 (July 1, 1998): 257–67. http://dx.doi.org/10.1530/jrf.0.1130257.

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Sistina, Yulia, and John C. Rodger. "Arachidonic acid-induced acrosomal loss in the spermatozoa of a marsupial, the tammar wallaby (Macropus eugenii)." Reproduction, Fertility and Development 9, no. 8 (1997): 803. http://dx.doi.org/10.1071/r95217.

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Tammar wallaby spermatozoa were induced to undergo acrosomal loss when incubated with arachidonic acid (AA). Ultrastructural examination indicated that the AA-induced acrosomal loss occurred via multiple point fusions between the outer acrosomal membrane and the overlying plasma membrane. This form of acrosomal loss mimicked the physiological acrosome reaction (AR) seen in the sperm of eutherian mammals. The fusion event was limited to the acrosomal region of the plasma membrane and did not proceed past the peri-acrosomal ring. The entire acrosome was lost after AA treatment leaving no evidence of a persistent equatorial segment-like region. Ultrastructural evidence of AR-like membrane fusion was seen immediately on addition of 50 µg mL-1 AA and a large proportion of sperm examined after five min incubation were in the late stages of membrane fusion. Longer-term incubation with AA had deleterious effects on wallaby sperm motility. It remains to be determined whether the AA-induced membrane fusion observed here indicates that AA is involved in the marsupial AR. However, pretreatment of sperm with the protein kinase C (PKC) inhibitor HMG significantly reduced AA-induced acrosomal loss suggesting that AA may have acted via PKC. If this is so, AA is probably physiologically significant and a novel pathway may be operating during AR induction in marsupials.

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Sistina, Y., M. Lin, KE Mate, ES Robinson, and JC Rodger. "The unique stability of the marsupial sperm acrosomal membranes examined by unprotected freeze-thawing and treatment with the detergent Triton X-100." Reproduction, Fertility and Development 5, no. 1 (1993): 1. http://dx.doi.org/10.1071/rd9930001.

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In this study of the unique stability of the marsupial acrosome, experiments were carried out on the acrosomes of spermatozoa of the tammar wallaby (Macropus eugenii), common brushtail possum (Trichosurus vulpecula) and grey short-tailed opossum (Monodelphis domestica). Light microscopy showed that 4% of opossum and 15% of possum and wallaby spermatozoa lost their acrosomes after freeze-thawing. Electron microscopy revealed that freeze-thawing also induced changes in the acrosomal matrix of some acrosome intact spermatozoa. In both possum and wallaby, freeze-thawing increased the number of spermatozoa with vesiculation of the acrosomal matrix. Freeze-thawing disrupted the plasma membrane of spermatozoa but the acrosomal membranes remained intact. Immediately on addition of high concentrations of TX-100 (0.02% and 0.04%) there was significant loss of acrosomes and motility in possum and wallaby spermatozoa. Lower concentrations of TX-100 (< or = 0.01%) did not affect motility for up to 30 min in all three species, and there was no significant loss of acrosomes. Although loss of acrosomes did not occur under mild detergent treatment, 56% of wallaby and 70% of possum spermatozoa had altered acrosomes after 30 min in 0.01% TX-100. Electron microscopy revealed that acrosomes were undergoing a vesiculation process similar to that seen after freeze-thawing. Often the plasma membrane of detergent-treated spermatozoa was disrupted and had formed plasma membrane vesicles. However, the acrosomal membranes remained intact despite major changes to the acrosomal matrix. The study confirmed the remarkable stability of the marsupial acrosome and suggested that this is probably based in the acrosomal membranes.

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Jones, RC, and J. Clulow. "Interactions of sperm and the reproductive ducts of the male tammar wallaby, Macropus eugenii (Macropodidae: Marsupialia)." Reproduction, Fertility and Development 6, no. 4 (1994): 437. http://dx.doi.org/10.1071/rd9940437.

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This review compares sperm production in the tammar wallaby and eutherian mammals, particularly the rat. The capacity of sperm to fertilize an ovum when they leave the testis and the changes they undergo in the epididymidis are considered. The structural differentiation and regulation of the extratesticular duct system is assessed and related to the reabsorption and secretion of water, inorganic ions and proteins, and the interaction of sperm and proteins synthesized and secreted by the epididymidis. Adaptations of the cauda epididymidis for storing spermatozoa are also considered. It is suggested that the tammar may be a good animal model to study the suppression of sperm motility and metabolism in the cauda epididymidis as it is possible to collect from them luminal samples of sperm which are initially immotile and then spontaneously activate during incubation in vitro.

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Clulow, J., R. C. Jones, and R. N. Murdoch. "Maturation and regulation of the motility of spermatozoa in the epididymis of the tammar wallaby (Macropus eugenii)." Reproduction 94, no. 2 (March 1, 1992): 295–303. http://dx.doi.org/10.1530/jrf.0.0940295.

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Hu, Yanqiu, Hongshi Yu, Andrew J. Pask, Deborah A. O'Brien, Geoff Shaw, and Marilyn B. Renfree. "A-kinase anchoring protein 4 has a conserved role in mammalian spermatogenesis." REPRODUCTION 137, no. 4 (April 2009): 645–53. http://dx.doi.org/10.1530/rep-08-0337.

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A-kinase anchor protein 4 (AKAP4) is an X-linked member of the AKAP family of scaffold proteins that anchor cAMP-dependent protein kinases and play an essential role in fibrous sheath assembly during spermatogenesis and flagellar function in spermatozoa. Marsupial spermatozoa differ in structural organization from those of eutherian mammals but data on the molecular control of their structure and function are limited. We therefore cloned and characterized the AKAP4 gene in a marsupial, the tammar wallaby (Macropus eugenii). The gene structure, sequence, and predicted protein of AKAP4 were highly conserved with that of eutherian orthologues and it mapped to the marsupial X-chromosome. There was no AKAP4 expression detected in the developing young. In the adult, AKAP4 expression was limited to the testis with a major transcript of 2.9 kb. AKAP4 mRNA was expressed in the cytoplasm of round and elongated spermatids while its protein was found on the principal piece of the flagellum in the sperm tail. This is consistent with its expression in other mammals. Thus, AKAP4 appears to have a conserved role in spermatogenesis for at least the last 166 million years of mammalian evolution.

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SCARLETT, CHRIS J., MINJIE LIN, and R. JOHN AITKEN. "Actin polymerisation during morphogenesis of the acrosome as spermatozoa undergo epididymal maturation in the tammar wallaby (Macropus eugenii )." Journal of Anatomy 198, no. 1 (January 2001): 93–101. http://dx.doi.org/10.1046/j.1469-7580.2001.19810093.x.

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Hu, Y., H. Yu, A. J. Pask, D. A. O.'Brien, G. Shaw, and M. B. Renfree. "440. A-kinase anchoring protein 4 in the marsupial." Reproduction, Fertility and Development 20, no. 9 (2008): 120. http://dx.doi.org/10.1071/srb08abs440.

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A-Kinase Anchor Protein 4 (AKAP4) is an X-linked member of the AKAP family of scaffold proteins that anchor cAMP-dependent protein kinases and play an essential role in fibrous sheath assembly during spermatogenesis and flagellar function in spermatozoa. Marsupial spermatozoa differ in structural organisation from those of eutherian mammals but data on the molecular control of their structure and function are limited. We therefore cloned and characterised the AKAP4 gene in a marsupial, the tammar wallaby (Macropus eugenii). The gene structure, sequence and predicted protein of AKAP4 were highly conserved with that of eutherian orthologueues and it mapped to the marsupial X-chromosome. There was no AKAP4 expression detected in the developing young and in the adult, expression was limited to the testis with a major transcript of 2.9kb identified by northern blotting. AKAP4 mRNA was detected by in situ hybridisation in the cytoplasm of round and elongated spermatids in the adult testis while its protein was found in the sperm tail from principal piece of the flagellum. This is consistent with its expression in other mammals. Thus this gene appears to have a conserved role in spermatogenesis for at least the last 166 million years of mammalian evolution.

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Magarey, Genevieve M., and Karen E. Mate. "Timing and ultrastructure of events following intracytoplasmic sperm injection in a marsupial, the tammar wallaby (Macropus eugenii)." Reproduction, Fertility and Development 15, no. 7 (2003): 397. http://dx.doi.org/10.1071/rd03033.

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The aim of the present study was to determine the timing of oocyte activation, sperm decondensation and pronucleus formation after intracytoplasmic sperm injection (ICSI) in the tammar wallaby and to determine the fate of sperm structures at an ultrastructural level. Metaphase II-stage tammar wallaby oocytes were injected with spermatozoa and cultured for 1 (n = 15), 2 (n = 24), 4 (n = 30), 6 (n = 14), 8 (n = 32), 10 (n = 25), 12 (n = 29) or 19 h (n = 12). Oocytes were assessed using light, fluorescence and electron microscopy. The timing of oocyte activation and sperm decondensation after ICSI in the tammar wallaby is relatively similar to that of some eutherian species. Resumption of meiosis II was observed from 1 h and the first female pronucleus was seen 6 h after ICSI. Most oocytes (88%) possessed a female pronucleus by 10 h. Intact acrosomes persisted with intact sperm heads up to 2 h after ICSI. At 10 h, 80% of oocytes possessed a male pronucleus. The sperm tail had undergone considerable degeneration by 10 h after ICSI, including breakdown of the fibrous sheath dense fibres. The identification of sperm tail and midpiece remnants adjacent to pronuclei confirms that the events observed in wallaby oocytes after ICSI are not due to parthenogenetic activation.

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Zhang, Xiyi, and Minjie Lin. "Tracing sperm acrosome differentiation in the testis and maturation in the epididymis of the tammar wallaby (Macropus eugenii) with a 45-kDa acrosome-membrane-associated protein." Reproduction, Fertility and Development 14, no. 2 (2002): 69. http://dx.doi.org/10.1071/rd01116.

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A 45-kDa protein was originally extracted from a depression, where the acrosome is lodged, on the anterior end of the sperm nucleus of ejaculated wallaby spermatozoa. Using immunofluorescent and confocal microscopes, this study demonstrates that the 45-kDa protein is persistently localized to the sperm acrosome throughout the periods of spermiogenesis, spermiation, epididymal maturation and ejaculation in the tammar wallaby. The distribution of the 45-kDa protein is always on the perimeter of the acrosome and associated with the acrosomal membrane, so that changes in the shape of the 45-kDa immunofluorescent labelling mirror changes in the shape of the acrosome during its differentiation in the testis and epididymis. Thus, the 45-kDa protein may be used as a molecular marker to study the marsupial acrosome differentiation and to chart the events of testicular and epididymal maturation of the spermatozoa. Furthermore, the behaviour of the 45-kDa protein during the immunostaining process suggests that this protein is a largely insoluble and detergent-resistant protein and may play an important role in attachment of the acrosome to the nucleus during sperm formation, similar to those inner acrosomal-membrane-associated proteins that have been reported in eutherian spermatozoa.

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Lin, Minjie, Xiyi Zhang, Ray N. Murdoch, and R. John Aitken. "Swim-up of tammar wallaby (Macropus eugenii) spermatozoa in Biggers, Whitter and Whittingham (BWW) medium: maximisation of sperm motility, minimisation of impairment of sperm metabolism and induction of sperm hyperactivation." Reproduction, Fertility and Development 29, no. 2 (2017): 345. http://dx.doi.org/10.1071/rd15152.

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A variety of media were compared for their ability to sustain the motility of tammar wallaby spermatozoa over an 8-h period following swim–up from coagulated semen. The study demonstrated that a modified Tyrode’s solution, Biggers, Whitter and Whittingham medium (BWW) was significantly better than any of the other assessed media in supporting wallaby sperm motility. After 8 h of incubation in BWW, motility was maintained at 79.3 ± 9.3%, with 77.0 ± 10.4% rapid and 65.7 ± 8.7% progressively motile spermatozoa. By contrast, motility was <10% at the same 8-h time point in all of the other media assessed. After 2 h of incubation in BWW, tammar spermatozoa consumed more oxygen than their counterparts in PBS (52.0 ± 2.7 vs 75.0 ± 6.6 μL per 108 spermatozoa per 2 h; P < 0.001). Motility was not enhanced in any of these media by the addition of 5 mM N-acetyl-D-glucosamine, the major energy substrate in wallaby semen. However, addition of dibutyryl cAMP and pentoxifylline in BWW resulted in the extremely rapid induction of hyperactivated motility in the entire sperm population. This burst of hyperactivated motility was entirely dependent on calcium in BWW and significantly inhibited by calmidazolium, a calmodulin inhibitor. A set of computer-assisted sperm analysis parameters were identified that permitted the accurate quantification of hyperactivation rates in this species. This is the first comparative analysis of media for harvesting and incubating marsupial spermatozoa and the first record of hyperactivated motility in any marsupial species.

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Bennetts, L. E., and R. J. Aitken. "215.Analysis of DNA damage induced by pro-oxidant treatment of mammalian spermatozoa in vitro." Reproduction, Fertility and Development 16, no. 9 (2004): 215. http://dx.doi.org/10.1071/srb04abs215.

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Defects in the male genome produced as a consequence of oxidative insult have been associated with decreased fertility levels, an elevated incidence of childhood cancer and dominant genetic disease in the offspring (1). The objective of this study was to determine the relative susceptibility of sperm DNA of different mammalian species to oxidative injury. We applied a highly sensitive quantitative PCR assay (QPCR) to measure gene-specific DNA damage in nuclear and mitochondrial compartments of spermatozoa treated with H2O2. Human, murine and tammar wallaby (Macropus eugenii) spermatozoa were treated with H2O2 (0–5�mM) over a 1�h period. After DNA purification, DNA damage was assessed in a nuclear and a mitochondrial fragment of DNA by quantitative polymerase chain reaction assay (QPCR). DNA damage was detected as a decrease amplification of the target sequences. In murine and human spermatozoa, mitochondrial DNA exhibited greater sensitivity to oxidative damage than nuclear DNA. Doses ranging from 0.25–5�mM H2O2 induced DNA damage of up to 0.65 lesions/10�kb in the mouse, and 1.42 lesions /10�kb in the human. No significant effect on DNA damage was observed over this dose range in the nuclear DNA fragments investigated in these species. In contrast, tammar wallaby spermatozoa were susceptible to DNA damage at the 5�mM H2O2 dose in both nuclear (0.51 lesions/10�kb) and mitochondrial (0.55 lesions/10�kb) genomes. This study is the first to compare DNA damage in specific DNA sequences in spermatozoa of different mammalian species. Nuclear DNA of the metatherian species, the tammar wallaby, was more susceptible to oxidative damage than that of the eutherian species. A major difference between metatherian and eutherian spermatozoa is that, in general, the former possess protamines that are not stabilised by disulfide cross-linkage. These findings therefore suggest that sperm chromatin packaging affects the susceptibility of sperm DNA to oxidative damage. (1) Sawyer and Aitken (2000) Reprod. Med. Rev. 8, 107–126.

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Sidhu, K. S., K. E. Mate, T. Gunasekera, D. Veal, L. Hetherington, M. A. Baker, R. J. Aitken, and J. C. Rodger. "A flow cytometric assay for global estimation of tyrosine phosphorylation associated with capacitation of spermatozoa from two marsupial species, the tammar wallaby (Macropus eugenii) and the brushtail possum (Trichosurus vulpecula)." Reproduction 127, no. 1 (January 2004): 95–103. http://dx.doi.org/10.1530/rep.1.00073.

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The phosphorylation of tyrosine residues in cellular proteins is a major signal transduction event during sperm capacitation. In this study protein phosphorylation was monitored using a fluorescein isothiocyanate (FITC)-labeled antiphosphotyrosine monoclonal antibody and a flow cytometric procedure optimized for sperm. Using this technique, the correlation between tyrosine phosphorylation and sperm capacitation was examined in two marsupial species, the brushtail possum and the tammar wallaby and compared with that of ram spermatozoa. The levels of tyrosine phosphorylation in sperm from all three species were increased by the addition of cyclic AMP (cAMP) and vandate, a phosphotyrosine phosphatase inhibitor and were decreased by the addition of the phosphotyrosine kinase inhibitor, staurosporine. Oviductal conditioned media (CM) induced a progressive increase in tyrosine phosphorylation in both marsupial species and also induced morphological transition from a streamlined to a ‘T’-shape configuration in brushtail possum spermatozoa but not in tammar wallaby spermatozoa. Transition to the ‘T’-shape orientation associated with capacitation in marsupial spermatozoa was observed by 2 h of incubation in both species when tyrosine phosphorylation was increased by higher levels of cAMP i.e. 5 mM dibutyryl cAMP plus 3 mM pentoxyphylline. Thus the tyrosine phosphorylation trigger with CM may differ in these two marsupial species. Ram sperm tyrosine phosphorylation could be increased by addition of lower levels of cAMP (1 mM). These results support the finding that tyrosine phosphorylation is associated with sperm capacitation in marsupials. Similar results were obtained by using SDS PAGE/Western blot analysis of tyrosine phosphorylation in the brushtail possum spermatozoa. The specificity, efficiency and sensitivity of the procedure described here make it applicable for routine assessment of capacitation in large numbers of samples and in other species.

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Asquith, Kelly L., Anne L. Kitchener, and David J. Kay. "Immunisation of the male tammar wallaby (Macropus eugenii) with spermatozoa elicits epididymal antigen-specific antibody secretion and compromised fertilisation rate." Journal of Reproductive Immunology 69, no. 2 (April 2006): 127–47. http://dx.doi.org/10.1016/j.jri.2005.08.004.

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Harris, Merrilee S., and John C. Rodger. "Characterisation of an epitope shared by an acrosomal acrosin-like protein and the surface of tammar wallaby (Macropus eugenii) spermatozoa." Journal of Experimental Zoology Part A: Comparative Experimental Biology 303A, no. 8 (2005): 713–21. http://dx.doi.org/10.1002/jez.a.193.

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Magarey, Genevieve M., and Karen E. Mate. "Fertilization following intracytoplasmic sperm injection of in vivo and in vitro matured oocytes from an Australian marsupial, the tammar wallaby (Macropus eugenii)." Zygote 11, no. 4 (November 2003): 339–46. http://dx.doi.org/10.1017/s0967199403002430.

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Conventional in vitro fertilization (IVF) techniques have been unable to produce normal embryos in any Australian marsupial, largely owing to problems with the early stages of sperm–oocyte binding. This study has used intracytoplasmic sperm injection (ICSI) of in vivo and in vitro matured tammar wallaby oocytes to bypass these processes and achieve fertilization in vitro. The fertilization rate (i.e. development to the two-pronuclei stage) of in vivo and in vitro matured oocytes following ICSI and sham injection was assessed at 17–19 h after injection. Fertilization occurred in 48% (45/93) of in vivo matured oocytes that were injected with spermatozoa. Significantly fewer sham-injected oocytes (6/82, P<0.005) and uninjected control oocytes (5/84, P<0.005) formed two pronuclei. In a direct comparison, the numbers of in vivo and in vitro matured oocytes that formed two pronuclei after ICSI were 22/28 (78.6%) and 23/40 (57.6%), respectively, which are not significantly different. There was also no significant difference in the nuclear response of in vivo and in vitro matured oocytes to sham injection. The numbers of oocytes forming a single pronucleus after sham injection were 10/24 (41.7%) and 24/37 (64.9) for in vivo and in vitro matured oocytes, respectively. Immature germinal-vesicle-stage oocytes were unable to decondense sperm injected during ICSI or to form pronuclei. These results demonstrate that both in vitro and in vivo matured tammar wallaby oocytes can be fertilized by ICSI. The success of ICSI not only offers the opportunity for fundamental analysis of marsupial fertilization but could, in conjunction with development of appropriate culture conditions and embryo transfer technologies, contribute to increased production of offspring from rare or valuable marsupials.

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Lin, Minjie, Yulia Sistina, and John C. Rodger. "Electron-microscopic localisation of thiol and disulphide groups by direct monomaleimido-nanogold labelling in the spermatozoa of a marsupial, the tammar wallaby ( Macropus eugenii )." Cell and Tissue Research 282, no. 2 (October 1, 1995): 291–96. http://dx.doi.org/10.1007/s004410050480.

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Lin, Minjie, Yulia Sistina, and John C. Rodger. "Electron-microscopic localisation of thiol and disulphide groups by direct monomaleimido-nanogold labelling in the spermatozoa of a marsupial, the tammar wallaby (Macropus eugenii)." Cell & Tissue Research 282, no. 2 (November 1995): 291–96. http://dx.doi.org/10.1007/bf00319119.

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Mate, K. E., and J. C. Rodger. "Stability of the acrosome of the brush-tailed possum (Trichosurus vulpecula) and tammar wallaby (Macropus eugenii) in vitro and after exposure to conditions and agents known to cause capacitation or acrosome reaction of eutherian spermatozoa." Reproduction 91, no. 1 (January 1, 1991): 41–48. http://dx.doi.org/10.1530/jrf.0.0910041.

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Richings, Nadine M., Geoffrey Shaw, Peter D. Temple-Smith, and Marilyn B. Renfree. "Intra-cytoplasmic sperm injection in a marsupial." Reproduction 128, no. 5 (November 2004): 595–605. http://dx.doi.org/10.1530/rep.1.00270.

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Here we report the first use of intra-cytoplasmic sperm injection (ICSI) in a marsupial, the tammar wallaby (Macropus eugenii ), to achieve in vitro fertilization and cleavage. A single epididymal spermatozoon was injected into the cytoplasm of each mature oocyte collected from Graafian follicles or from the oviduct within hours of ovulation. The day after sperm injection, oocytes were assessed for the presence of pronuclei and polar body extrusion and in vitro development was monitored for up to 4 days. After ICSI, three of four (75%) follicular and four of eight (50%) tubal oocytes underwent cleavage. The cleavage pattern was similar to that previously reported for in vivo fertilized oocytes placed in culture, where development also halted at the 4- to 8-cell stage. One-third of injected oocytes completed the second cleavage division, but only a single embryo reached the 8-cell stage. The success of ICSI in the tammar wallaby provided an opportunity to examine the influence of the mucoid coat that is deposited around oocytes passing through the oviduct after fertilization. The presence of a mucoid coat in tubal oocytes did not prevent fertilization by ICSI and the oocytes cleaved in vitro to a similar stage as follicular oocytes lacking a mucoid coat. Cell–zona and cell–cell adhesion occurred in embryos from follicular oocytes, suggesting that the mucoid coat is not essential for these processes. However, blastomeres were more closely apposed in embryos from tubal oocytes and cell–cell adhesion was more pronounced, indicating that the mucoid coat may be involved in maintaining the integrity of the conceptus during cleavage.

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Lin, M., R. Hess, and RJ Aitken. "Induction of sperm maturation in vitro in epididymal cell cultures of the tammar wallaby (Macropus eugenii): disruption of motility initiation and sperm morphogenesis by inhibition of actin polymerization." Reproduction, July 1, 2002, 107–17. http://dx.doi.org/10.1530/rep.0.1240107.

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A sperm-epididymal cell co-culture was shown to be capable of inducing the in vitro maturation of spermatozoa from a marsupial species, the tammar wallaby (Macropus eugenii). This system was able to maintain wallaby epididymal epithelial cells in vitro for more than 2 months. The system also enabled immature wallaby spermatozoa to differentiate from a T-shaped to a streamlined form, accompanied by the development of progressive motility after co-culture with epididymal cell monolayers that had been cultured for 7 days. The addition of inhibitors of actin polymerization (latrunculin A or B) to the co-culture system showed that wallaby sperm maturation was impaired by the interruption of actin organization within the immature spermatozoa. These results indicate that actin filaments play a significant role in sperm transformation during post-testicular maturation in marsupials. These observations also indicate that the marsupial co-culture system has the potential to greatly increase understanding of sperm-epididymal cell interactions and the mechanism of sperm maturation in these species.

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Journal articles on the topic 'Macropus eugenii Spermatozoa'

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