Busslinger M, Portmann R, Birnsteil M L
Nucleic Acids Res. 1979 Jul 11;6(9):2997-3008. doi: 10.1093/nar/6.9.2997.
The 3' flanking sequences of all five histone genes have been sequenced in the histone DNA clone h19 of the sea urchin Psammechinus miliaris. A large (23 bp) and a small (10 bp) conserved sequence was found by sequence comparison, some 29-40 bp downstream from the termination codon. 12 bases of the larger homology block show a dyad symmetry. The available sequences of clone h22 of the same species and those of the histone clones pSp2 and pSp17 of Strongylocentrotus purpuratus, another sea urchin species, fit well into this comparison. Two types of sequences are involved in the dyad symmetry; one is H1, H3 and H4 specific, the other is H2A and H2B specific. If these conserved sequences are transcribed, a hairpin loop could form in the RNA molecules. This secondary structure might serve as a recognition signal for a regulatory protein.
在海胆光棘球海胆（Psammechinus miliaris）的组蛋白DNA克隆h19中，已对所有五个组蛋白基因的3'侧翼序列进行了测序。通过序列比较，在终止密码子下游约29 - 40 bp处发现了一个大的（23 bp）和一个小的（10 bp）保守序列。较大同源框的12个碱基呈现出二元对称性。同一物种克隆h22的现有序列以及另一种海胆物种紫球海胆（Strongylocentrotus purpuratus）的组蛋白克隆pSp2和pSp17的序列，与该比较结果非常吻合。二元对称性涉及两种类型的序列；一种是H1、H3和H4特异性的，另一种是H2A和H2B特异性的。如果这些保守序列被转录，RNA分子中可能会形成发夹环。这种二级结构可能作为一种调节蛋白的识别信号。
