The replacement histone H2A.Z in a hyperacetylated form is a feature of active genes in the chicken.
The replacement histone H2A.Z in a hyperacetylated form is a feature of active genes in the chicken.
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过乙酰化形式的替换组蛋白H2A.Z是鸡肉中活性基因的特征。
DOI：
10.1093/nar/gki874
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发表时间：
2005
影响因子：
14.9
通讯作者：
Crane-Robinson C
中科院分区：
文献类型：
--
作者：
Bruce K;Myers FA;Mantouvalou E;Lefevre P;Greaves I;Bonifer C;Tremethick DJ;Thorne AW;Crane-Robinson C
替换组蛋白H2A.Z被不同地报道为与基因表达相关并防止酵母中异染色质的扩散，或在哺乳动物中集中在异染色质。为了解决这一明显的二分法，在天然染色质免疫沉淀实验中使用来自三种鸡细胞类型的单核小体，在三乙酰化和非乙酰化状态下针对H2A.Z的N-末端区域的亲和纯化的抗体。超乙酰化的种类集中在活性基因的5′端，组织特异性和管家，但不存在于非活性基因中，而未乙酰化的形式在活性和非活性基因中均不存在。在绝缘体中也发现了H2A.Z的浓度，这意味着与屏障活性有关，但与增强子阻断无关。虽然乙酰化的H2A.Z广泛存在于间期基因组中，但在有丝分裂时，其乙酰化被清除，保留未修饰的形式。因此，虽然H2A.Z可以作为活性基因的表观遗传标记，但其N-末端乙酰化却不能。
The replacement histone H2A.Z is variously reported as being linked to gene expression and preventing the spread of heterochromatin in yeast, or concentrated at heterochromatin in mammals. To resolve this apparent dichotomy, affinity-purified antibodies against the N-terminal region of H2A.Z, in both a triacetylated and non-acetylated state, are used in native chromatin immmuno-precipitation experiments with mononucleosomes from three chicken cell types. The hyperacetylated species concentrates at the 5′ end of active genes, both tissue specific and housekeeping but is absent from inactive genes, while the unacetylated form is absent from both active and inactive genes. A concentration of H2A.Z is also found at insulators under circumstances implying a link to barrier activity but not to enhancer blocking. Although acetylated H2A.Z is widespread throughout the interphase genome, at mitosis its acetylation is erased, the unmodified form remaining. Thus, although H2A.Z may operate as an epigenetic marker for active genes, its N-terminal acetylation does not.