Recent molecular cytogenetic studies demonstrate that extensive centromere-telomere fusions are the main chromosomal rearrangements underlying the karyotypic evolution of extant muntjacs. Although the molecular mechan...Recent molecular cytogenetic studies demonstrate that extensive centromere-telomere fusions are the main chromosomal rearrangements underlying the karyotypic evolution of extant muntjacs. Although the molecular mechanism of tandem fusions remains unknown, satellite DNA is believed to have facilitated chromosome fusions by non-allelic homologous recombination. Previous studies detected non-random hybridization signals of cloned satellite DNA at the postulated fusion sites on the chromosomes in Indian and Chinese muntjacs. But the genomic distribution and organization of satellite DNAs in other muntjacs have not been investigated. In this study, we have isolated four satellite DNA clones （BMCS, BM700, BM 1.1 k and FM700） from the black muntjac （Muntiacus crinifrons） and Fea＇s muntjac （M. feae）, and hybridized these four clones onto chromosomes of four muntjac species （M. reevesi, M. crinifrons, M. gongshanenisis and M. feae）. Besides the predominant centromeric signals, non-random interstitial hybridization signals from satellite I and II DNA clones （BMC5, BM700 and FM700） were also observed on the arms of chromosomes of these four muntjacs. Our results provide additional support for the notion that the karyotypes of M. crinifrons, M. feae and M. gongshanensis have evolved from a 2n = 70 ancestral karyotype by a series of chromosome fusions.展开更多
基金the grant from the National Natural Science Foundation of China (30270719)
文摘Recent molecular cytogenetic studies demonstrate that extensive centromere-telomere fusions are the main chromosomal rearrangements underlying the karyotypic evolution of extant muntjacs. Although the molecular mechanism of tandem fusions remains unknown, satellite DNA is believed to have facilitated chromosome fusions by non-allelic homologous recombination. Previous studies detected non-random hybridization signals of cloned satellite DNA at the postulated fusion sites on the chromosomes in Indian and Chinese muntjacs. But the genomic distribution and organization of satellite DNAs in other muntjacs have not been investigated. In this study, we have isolated four satellite DNA clones （BMCS, BM700, BM 1.1 k and FM700） from the black muntjac （Muntiacus crinifrons） and Fea＇s muntjac （M. feae）, and hybridized these four clones onto chromosomes of four muntjac species （M. reevesi, M. crinifrons, M. gongshanenisis and M. feae）. Besides the predominant centromeric signals, non-random interstitial hybridization signals from satellite I and II DNA clones （BMC5, BM700 and FM700） were also observed on the arms of chromosomes of these four muntjacs. Our results provide additional support for the notion that the karyotypes of M. crinifrons, M. feae and M. gongshanensis have evolved from a 2n = 70 ancestral karyotype by a series of chromosome fusions.
