CAJ | 학술논문

近年来,分子细胞遗传学研究已基本证实了染色体的串联融合(端粒一着丝粒融合)是麂属动物核型演化的主要重排方式.尽管染色体串联融合的分子机制还不清楚,但通过染色体的非同源重组,着丝粒区域的卫星DNA被认为可能介导了染色体的融合.以前的研究发现在赤麂和小麂染色体的大部分假定的串联融合位点处存在着非随机分布的卫星DNA.然而在麂属的其他物种中,这些卫星DNA的组成以及在基因组中的分布情况尚未被研究.本研究从黑麂和费氏麂基因组中成功地克隆了4种卫星DNA (BMC5、BM700、BM1.1k和FM700),并分析了这些卫星克隆的特征以及在小麂、黑麂、贡山麂和费氏麂染色体上的定位情况.结果表明,卫星Ⅰ和Ⅱ DNA (BMC5,BM700和FM700)的信号除了分布在这些麂属动物染色体的着丝粒区域外,也间隔地分布在这些物种的染色体臂上.其研究结果为黑麂、费氏麂和贡山麂的染色体核型也是从一个2n=70的共同祖先核型通过一系列的串联融合进化而来的假说提供了直接的证据.
근년래,분자세포유전학연구이기본증실료염색체적천련융합(단립일착사립융합)시궤속동물핵형연화적주요중배방식.진관염색체천련융합적분자궤제환불청초,단통과염색체적비동원중조,착사립구역적위성DNA피인위가능개도료염색체적융합.이전적연구발현재적궤화소궤염색체적대부분가정적천련융합위점처존재착비수궤분포적위성DNA.연이재궤속적기타물충중,저사위성DNA적조성이급재기인조중적분포정황상미피연구.본연구종흑궤화비씨궤기인조중성공지극륭료4충위성DNA (BMC5、BM700、BM1.1k화FM700),병분석료저사위성극륭적특정이급재소궤、흑궤、공산궤화비씨궤염색체상적정위정황.결과표명,위성Ⅰ화Ⅱ DNA (BMC5,BM700화FM700)적신호제료분포재저사궤속동물염색체적착사립구역외,야간격지분포재저사물충적염색체비상.기연구결과위흑궤、비씨궤화공산궤적염색체핵형야시종일개2n=70적공동조선핵형통과일계렬적천련융합진화이래적가설제공료직접적증거.
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 (BMC5, BM700, BM1.lk 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.