Analysis of meiotic chromosome structure and behavior in Robertsonian heterozygotes of Ellobius tancrei (Rodentia, Cricetidae): a case of monobrachial homology
نویسندگان
چکیده
Synaptonemal complex (SC) chains were revealed in semisterile intraspecific F1 hybrids of Ellobius tancrei Blasius, 1884 (2n = 49, NF=56 and 2n=50, NF=56), heterozygous for Robertsonian (Rb) translocations. Chains were formed by Rb submetacentrics with monobrachial homology. Chromosome synapsis in spermatocytes of these hybrids was disturbed, apparently because of the problematic release of the chromosomes from the SC chains. These hybrids suffer from low fertility, and our data support the opinion that this is because a formation of Rb metacentrics with monobrachial homology within different races of the same species might be an initial event for the divergence of chromosomal forms.
منابع مشابه
A new form of the mole vole Ellobius tancrei Blasius, 1884 (Mammalia, Rodentia) with the lowest chromosome number
The subterranean mole vole, Ellobius tancrei, with aspecific variability in autosomes (2n = 31-54) and unusual sex chromosomes (XX in males and females), represents an amazing model for studying the role of chromosome changes in speciation. New materials from the upper reaches of the Surkhob River in the Pamiro-Alay mountains resulted in the discovery of a new form with 2n = 30. The application...
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