The DNA sequence of sea urchin (S. purpuratus) H2A, H2B and H3 histone coding and spacer regions
The DNA sequence of sea urchin (S. purpuratus) H2A, H2B and H3 histone coding and spacer regions
复制标题
海胆 (S. purpuratus) H2A、H2B 和 H3 组蛋白编码和间隔区的 DNA 序列
DOI：
10.1016/0092-8674(78)90287-8
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发表时间：
1978
期刊：
影响因子：
64.5
通讯作者：
L. Kedes
中科院分区：
文献类型：
--
作者：
I. Sures;Jean C. Lowry;L. Kedes
本文克隆了海胆S.已确定为紫色。一个序列含有连续的H2 B和H3基因及其相互交叉的间隔区;另一个包含H2 A基因和侧翼间隔区序列。对编码区的分析揭示了H2 A蛋白内的甲硫氨酸残基。H2 A通常缺乏这种氨基酸，仅在早期海胆胚胎发生中合成的蛋白质变体中含有甲硫氨酸。因此，我们得出结论，克隆的DNA代表了一组在发育早期活跃的基因，三个基因的密码子选择明显偏斜且相似。这些DNA序列与已知的组蛋白质序列是共线性的，而且不像其他几个真核基因，在编码区没有任何插入。间隔区是相对AT丰富的，虽然GC集群分散在整个。在蛋白质编码区段的上游和下游区域中发现几个短的同源性延伸。这些序列的保守性及其在类似位点的位置表明它们参与基因转录或mRNA翻译。没有发现串联或分散重复，除了具有以下结构的显著序列
The DNA sequence of two cloned segments of the histone gene repeat unit of the sea urchin S. purpuratus has been determined. One sequence contains the contiguous H2B and H3 genes and their interdigitated spacer regions; the other comprises the H2A gene and flanking spacer sequences. Analysis of the coding regions reveals a methionine residue within the H2A protein. H2A, which generally lacks this amino acid, contains methionine only in a protein variant which is syntheslzed in early sea urchin embryogenesis. We thus conclude that the cloned DNA represents a set of genes which is active early in development.Codon selection is markedly skewed and similar for each of the three genes. The DNA sequences are co-linear with known histone protein sequences and-unlike several other eucaryotic genes-do not show any insertions in the coding regions. The spacer regions are relatively AT-rich although GC clusters are scattered throughout. Several short stretches of homology are found in regions both upstream and downstream from the protein coding segments. The conservation of these sequences and their location at analogous sites suggest that they are involved in gene transcription or in mRNA translation. No tandem or dispersed repeats were found, with the exception of the remarkable sequence having the structure