Lakhotia S C, Kumar M
Cytobios. 1978;21(82):79-89.
The heterochromatin in mitotic cells of larval neural ganglia of Drosophila nasuta has been analysed by C-banding and by fluorescence studies. All chromosomes, except the 'dot'-like 4th chromosome pair, carry large blocks of heterochromatin which are darkly stained by C-banding, and which fluoresce uniformly brightly with Hoechst 33258, quinacrine mustard, and acridine orange. These heterochromatic segments make up about 40% of the total metaphase chromosome length. The heterochromatic segments also fluoresce brightly with all the dyes at the anaphase stage. In interphase nuclei, all the heterochromatic segments form a common, compact and homogeneous mass which fluoresces brightly with the three fluorochromes used. The size of the bright chromocentre is similar with all the dyes. It is suggested that the heterochromatic segments of different chromosomes are relatively homogeneous in their DNA base sequences, which are likely to be A-T rich in view of their bright fluorescence with Hoechst 33258 as well as quinacrine mustard.
已通过C带和荧光研究分析了纳氏果蝇幼虫神经节有丝分裂细胞中的异染色质。除点状的第4号染色体对外，所有染色体均带有大块异染色质，这些异染色质经C带染色后颜色很深，并且用Hoechst 33258、喹吖因芥子和吖啶橙染色后会均匀明亮地发出荧光。这些异染色质区段约占中期染色体总长度的40%。在后期阶段，异染色质区段用所有染料染色后也会发出明亮荧光。在间期核中，所有异染色质区段形成一个共同的、致密且均匀的团块，用所使用的三种荧光染料染色后会发出明亮荧光。用所有染料染色后，明亮染色中心的大小相似。有人提出，不同染色体的异染色质区段在其DNA碱基序列上相对均匀，鉴于它们在用Hoechst 33258以及喹吖因芥子染色后发出明亮荧光，其碱基序列可能富含A-T。
