Chromosomal repatterning in crocodiles: C, G and N-banding and the in situ hybridization of 18S and 26S rRNA cistrons
Chromosomal repatterning in crocodiles: C, G and N-banding and the in situ hybridization of 18S and 26S rRNA cistrons
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DOI：
10.1007/bf00122186
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发表时间：
1986-10
期刊：
影响因子：
1.5
通讯作者：
M. King;R. Honeycutt;N. Contreras
中科院分区：
文献类型：
--
作者：
M. King;R. Honeycutt;N. Contreras
使用 C、G 和 N 带带技术以及来自非洲爪蟾的 18S+26S rRNA 顺反子的原位杂交对多孔鳄、C. johnstonian 和凯门鳄的染色体进行了分析。很明显，除了众所周知的区分这些鳄鱼的总体结构变化（罗伯逊重排和中心周倒转）之外，还发生了许多其他模式的重新模式。这些涉及基因组的异染色质和常染色质部分。它们似乎与已确定的总体结构变化相关，并涉及两种不同形式的染色质转化。此外，这些鳄鱼染色体上的 18S+26S rRNA 顺反子的原位杂交已将核仁组织者活性位点定位于所有三个物种中存在的 C 带正 G 带负次级缢缩。讨论了这些结果的意义。
The chromosomes ofCrocodylus porosus, C. johnstoniandCaiman crocodilushave been analysed using C, G and N-banding techniques and thein situhybridization of 18S+26S rRNA cistrons derived fromXenopus. It is clear that in addition to the gross structural changes (robertsonian rearrangements and pericentric inversions) which are known to distinguish these crocodiles, numerous other modes of repatterning have occurred. These involved both the heterochromatic and euchromatic portions of the genome. They appear to be associated with the gross structural changes which have been established, and involve two distinct forms of chromatin transformation.In addition, thein situhybridization of 18S+26S rRNA cistrons onto these crocodilian chromosomes has localized the site of nucleolus organizer activity to the C-band positive G-band negative secondary constrictions present in all three species. The significance of these results is discussed.