Remodeling of sperm chromatin after fertilization involves nucleosomes formed by sperm histones H2A and H2B and two CS histone variants
Remodeling of sperm chromatin after fertilization involves nucleosomes formed by sperm histones H2A and H2B and two CS histone variants
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受精后精子染色质的重塑涉及由精子组蛋白 H2A 和 H2B 以及两种 CS 组蛋白变体形成的核小体
DOI：
10.1002/jcb.10179
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发表时间：
2002
影响因子：
4
通讯作者：
M. Imschenetzky
中科院分区：
文献类型：
--
作者：
M. Oliver;C. Concha;S. Gutiérrez;A. Bustos;M. Montecino;M. Puchi;M. Imschenetzky
测定了海胆雄性原核形成中期核小体的组成。从授精后 10 分钟收获的受精卵中分离出核小体，通过核酸酶消化从细胞核中获得整个核蛋白颗粒，随后通过蔗糖梯度分级纯化核小体。通过对与 Sepharose 4B（抗 SpH-Sepharose）共价结合的精子特异性组蛋白（抗 SpH）的抗体进行免疫吸附，将源自雄性原核的核小体与源自雌性原核的核小体分开。洗脱免疫吸附的核小体，并通过蛋白质印迹分析组蛋白。使用针对每组组蛋白的抗体来鉴定精子组蛋白 (SpH) 或来自未受精卵的组蛋白（CS 组蛋白变体）。研究发现，这些核小体由精子组蛋白 H2A 和 H2B 与两种主要 CS 组蛋白变体结合形成的核心组织而成。这种混合组蛋白核心与大约 100 bp 的 DNA 片段相互作用。研究还发现，这些非典型核小体核心随后被组织在染色质纤维中，该纤维表现出由 500 bp DNA 片段确定的周期性核酸酶超敏位点。发现这些核蛋白颗粒主要由上述杂合核小体组织而成。我们假设这种独特的染色质组织定义了受精后雄性染色质重塑的中间阶段。 J.细胞。生物化学。 85: 851–859, 2002。© 2002 Wiley-Liss, Inc.
The composition of nucleosomes at an intermediate stage of male pronucleus formation was determined in sea urchins. Nucleosomes were isolated from zygotes harvested 10 min post‐insemination, whole nucleoprotein particles were obtained from nucleus by nuclease digestion, and nucleosomes were subsequently purified by a sucrose gradient fractionation. The nucleosomes derived from male pronucleus were separated from those derived from female pronucleus by immunoadsorption to antibodies against sperm specific histones (anti‐SpH) covalently bound to Sepharose 4B (anti‐SpH‐Sepharose). The immunoadsorbed nucleosomes were eluted, and the histones were analyzed by Western blots. Sperm histones (SpH) or alternatively, the histones from unfertilized eggs (CS histone variants), were identified with antibodies directed against each set of histones. It was found that these nucleosomes are organized by a core formed by sperm histones H2A and H2B combined with two major CS histone variants. Such a hybrid histone core interacts with DNA fragments of approximately 100 bp. It was also found that these atypical nucleosome cores are subsequently organized in a chromatin fiber that exhibits periodic nuclease hypersensitive sites determined by DNA fragments of 500 bp of DNA. It was found that these nucleoprotein particles were organized primarily by the hybrid nucleosomes described above. We postulate that this unique chromatin organization defines an intermediate stage of male chromatin remodeling after fertilization. J. Cell. Biochem. 85: 851–859, 2002. © 2002 Wiley‐Liss, Inc.