Amino acid sequence and sequence variability of the amino-terminal regions of lysine-rich histones.
Amino acid sequence and sequence variability of the amino-terminal regions of lysine-rich histones.
复制标题
富含赖氨酸的组蛋白氨基末端区域的氨基酸序列和序列变异性。
DOI：
10.1016/s0021-9258(19)45870-5
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发表时间：
1971
期刊：
影响因子：
--
通讯作者：
R. Cole
中科院分区：
文献类型：
--
作者：
S. C. Rall;R. Cole
测定了兔胸腺富含赖氨酸的组蛋白的前72个残基的氨基酸序列。这些残基包含在用n -溴琥珀酰亚胺处理后从组蛋白释放的片段中。通过胰蛋白酶、热溶素和胰糜蛋白酶消化这72个残基片段得到的肽段被用来重建总序列。对该序列的分析揭示了该片段结构的一些不寻常的方面，该片段约占组蛋白分子的三分之一。前40个残基中有30个由赖氨酸、丙氨酸和脯氨酸组成；这部分片段包括4、2和3个连续的基本残基序列。最后32个残基包含该片段的所有疏水氨基酸（缬氨酸、异亮氨酸、亮氨酸、酪氨酸），但基本残基很少，不含脯氨酸。组蛋白的nh2端被乙酰化。将这种富含赖氨酸的组蛋白的nh2末端一半序列与稍微富含赖氨酸和精氨酸的组蛋白的整个序列进行比较，发现它们具有相似的特征，即nh2末端区域富含碱性氨基酸，cooh末端部分富含疏水残基。从另外两个胸腺赖氨酸丰富的组蛋白的nh2末端n -溴琥珀酰亚胺片段中分离出了色氨酸肽。这些多肽（部分序列）与先前研究的富含赖氨酸的组蛋白的nh2末端n -溴琥珀酰亚胺片段的完整氨基酸序列直接相同或相似。结果表明，各馏分之间存在7 ~ 14个氨基酸的差异。其中一个氨基酸互换消除了一个主要的磷酸化位点。
The amino acid sequence has been determined for the first 72 residues of a lysine-rich histone from rabbit thymus. These are the residues contained in a fragment released from the histone by treatment withN-bromosuccinimide. Peptides derived by tryptic, thermolysin, and chymotryptic digestion of this 72-residue fragment were used to reconstruct the total sequence.Analysis of the sequence revealed some unusual aspects of the structure of the fragment, which comprises about one-third of the histone molecule. Thirty of the first 40 residues are accounted for by lysine, alanine, and proline; this portion of the fragment includes sequences of 4, 2, and 3 consecutive basic residues. The last 32 residues contain all the hydrophobic amino acids (valine, isoleucine, leucine, tyrosine) of the fragment but have few basic residues and no prolines. The NH2terminus of the histone is acetylated.Comparison of the sequence of the NH2-terminal half of this lysine-rich histone with the entire sequences of the slightly lysine-rich and arginine-rich histones shows that all three have similar characteristics, that is, an NH2-terminal region rich in basic amino acids and a COOH-terminal portion rich in hydrophobic residues.Tryptic peptides from the NH2-terminalN-bromosuccinimide fragment of two other thymus lysine-rich histones have been isolated. These peptides (with partial sequences) were aligned by direct identity or analogy with the complete amino acid sequence of the NH2-terminalN-bromosuccinimide fragment of the lysine-rich histone studied previously. It was found that there were from 7 to 14 amino acid differences between fractions. One of the amino acid interchanges eliminates a major phosphorylation site.