Pardue M L, Kedes L H, Weinberg E S, Birnstiel M L
Chromosoma. 1977 Aug 25;63(2):135-51. doi: 10.1007/BF00292726.
In situ hybridization of sea urchin (Psammechinus miliaris, Lytechinus pictus and Strongylocentrotus purpuratus) histone messenger RNA has been used to map complementary sequences on polytene chromosomes from Drosophila melanogaster. The sea urchin RNA hybridizes to the polytene regions from 39D3 through 39E1-2, including both of these bands (39D2 may also be included). This region is identical to the one which hybridizes most heavily with non-polyadenylated cytoplasmic RNA from D. melanogaster tissues. Sea urchin mRNAs coding for several individual histones each hybridize across the entire region from 39D3 (or D2) through 39E1-2, as would be expected if the individual mRNA sequences are interspersed. In view of the apparently even distribution of sequences complementary to histone mRNA within the 39D3-39E1-2 region, the significance of the several polytene bands in this region remains an open question. Biochemical characterization of the hybrids between sea urchin histone mRNA and D. melanogaster DNA suggest that sea urchin mRNAs for several of the histone classes have some portions which retain enough sequence homology with the D. melanogaster sequences to form hybrids, although the hybrids have base pair mismatches. In situ hybridization of chromosomes in which region 39-E is ectopically paired show no evidence of seqence homology in the chromosome region with which 39D-E is associated.
海胆（米氏砂海胆、多色灯海胆和紫球海胆）组蛋白信使核糖核酸的原位杂交已被用于在黑腹果蝇的多线染色体上定位互补序列。海胆核糖核酸与从39D3到39E1 - 2的多线区域杂交，包括这两条带（39D2也可能包括在内）。该区域与黑腹果蝇组织中与非聚腺苷酸化细胞质核糖核酸杂交最强烈的区域相同。编码几种单个组蛋白的海胆信使核糖核酸各自在从39D3（或D2）到39E1 - 2的整个区域杂交，如果单个信使核糖核酸序列是散布的，这是可以预期的。鉴于在39D3 - 39E1 - 2区域内与组蛋白信使核糖核酸互补的序列明显均匀分布，该区域中几个多线带的意义仍然是一个悬而未决的问题。海胆组蛋白信使核糖核酸与黑腹果蝇脱氧核糖核酸之间杂交体的生化特性表明，几种组蛋白类别的海胆信使核糖核酸有一些部分与黑腹果蝇序列保留了足够的序列同源性以形成杂交体，尽管杂交体存在碱基对错配。对39 - E区域异位配对的染色体进行原位杂交，未显示出与39D - E相关的染色体区域有序列同源性的证据。
