Probing the meiotic mechanism of intergenomic exchanges by genomic in situ hybridization on lampbrush chromosomes of unisexual Ambystoma (Amphibia: Caudata)

@article{Bi2010ProbingTM,
  title={Probing the meiotic mechanism of intergenomic exchanges by genomic in situ hybridization on lampbrush chromosomes of unisexual Ambystoma (Amphibia: Caudata)},
  author={Ke Bi and James P. Bogart},
  journal={Chromosome Research},
  year={2010},
  volume={18},
  pages={371-382}
}
The meiotic mechanism of unisexual salamanders in the genus Ambystoma was previously explained by observing lampbrush chromosomes (LBCs). In polyploid unisexual females, a pre-meiotic endomitotic event doubles the chromosome number so that, after meiotic reduction, the mature eggs have the same ploidy as the female. It was assumed that synapses during meiotic I prophase, which result in observed bivalents, join duplicated sister chromosomes. Previous studies also found LBC quadrivalents in some… Expand
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RELATING HYBRID ADVANTAGE AND GENOME REPLACEMENT IN UNISEXUAL SALAMANDERS
  • N. Charney
  • Biology, Medicine
  • Evolution; international journal of organic evolution
  • 2012
TLDR
A conceptual model is presented that relates nuclear genome replacement, positive selection on hybrids and biogeography in unisexual systems and finds that, if genome replacement occurs at a rate greater than 1/10,000 in Ambystoma, then there must be compensating positive selection in order to maintain observed levels of hybrid nuclei. Expand
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References

SHOWING 1-10 OF 45 REFERENCES
An examination of intergenomic exchanges in A. laterale-dependent unisexual salamanders in the genus Ambystoma
TLDR
Observations show that the patterns and frequencies of intergenomic exchanges are different when unisexuals use different sexual species as sperm donors, and propose a few possible mechanisms that may account for these different observations. Expand
Intergenomic translocations in unisexual salamanders of the genus Ambystoma (Amphibia, Caudata)
TLDR
Intergenomic translocations and homoeologous recombinations appear to be frequent chromosome reconstruction events among unisexual Ambystoma, and are believed to be caused by non-homologous pairing during meiosis followed by breakage-rejoining events. Expand
Meiotic Mechanisms of Naturally Occurring Unisexual Vertebrates
TLDR
A premeiotic mitosis without cytokinesis is more probably the oogenic pathway used by unisexual Lacerta, since it is consistent with the observations (two meiotic divisions), but avoids the difficulties associated with homozygosity, which would rapidly result from suppressing the second meiotic division. Expand
Identification of intergenomic recombinations in unisexual salamanders of the genus Ambystoma by genomic in situ hybridization (GISH)
TLDR
GISH is an effective tool that can be used to identify and to quantify genomic constituents and to investigate intergenomic interactions in unisexual salamanders and has potential application to examine possible genomic evolution in other unisexuals. Expand
Two rare aneutriploids in the unisexual Ambystoma (Amphibia, Caudata) identified by GISH indicating two different types of meiotic errors
TLDR
This study provides additional evidence for the extremely flexible reproduction of unisexual Ambystoma and indicates that contemporary intergenomic exchanges and homoeologous recombinations may occur after a premeiotic chromosome doubling event. Expand
Premeiotic endomitosis produces diploid eggs in the natural clone loach, Misgurnus anguillicaudatus (Teleostei: Cobitidae).
TLDR
The results suggest that chromosomes are duplicated by mitosis without cytokinesis before meiosis, i.e. premeiotic endomitosis and then oocytes differentiated from tetraploid oogonia undergo a quasinormal meiosis followed by two successive divisions to produce diploid eggs. Expand
Genealogical relationships of southern Ontario polyploid unisexual salamanders (genus Ambystoma) inferred from intergenomic exchanges and major rDNA cytotypes
TLDR
The results suggest that current LJJ and LJJJ populations in southern Ontario are likely derived from a few unisexual individuals, and similar methods may be applied for studying the molecular cytogenetics of other unisexuals to improve the understanding of their genealogical relationships and historical dispersal. Expand
The prevalence of genome replacement in unisexual salamanders of the genus Ambystoma (Amphibia, Caudata) revealed by nuclear gene genealogy
TLDR
It is demonstrated that genome replacement frequently occurs in unisexual Ambystoma across their range, and support previous speculations that genome Replacement is an important reproductive mechanism that can enhance their evolutionary longevity. Expand
Structural differentiation of the meiotic and mitotic chromosomes of the salamander, Ambystoma macrodactylum
TLDR
The lampbrush chromosomes of the long-toed salamander, Ambystoma macrodactylum Baird, have been analysed and a map of the oocyte genome prepared and an analysis of the similarities and differences that are visible in the chromosome sets of these two ambystomatid species are presented. Expand
Sex in unisexual salamanders: discovery of a new sperm donor with ancient affinities
TLDR
Examining unisexual adults and larvae in a southern Ohio pond provided an opportunity to test hypotheses pertaining to the role of A. barbouri in the evolution of the disparate cytoplasmic and nuclear genomes in unisexual salamanders and demonstrated the evolutionary flexibility and dynamics of kleptogenesis. Expand
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