RPD3-type histone deacetylases in maize embryos
RPD3-type histone deacetylases in maize embryos
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DOI：
10.1021/bi9918184
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发表时间：
2000-02-22
期刊：
影响因子：
2.9
通讯作者：
Loidl, P
中科院分区：
文献类型：
--
作者：
Lechner, T;Lusser, A;Loidl, P
翻译后核心组蛋白乙酰化由组蛋白乙酰转移酶和去乙酰化酶建立和维持。两者都已被确定为在各种真核生物系统中的重要转录调控因子。在非植物系统中，只有RPD 3相关的组蛋白脱乙酰酶（HD）的特点，到目前为止，玉米胚含有三个不相关的家庭的脱乙酰酶（HD 1A，HD 1B，和HD2）。纯化，cDNA克隆，和免疫学研究确定了两个玉米组蛋白脱乙酰酶HD 1B形式的RPD 3型脱乙酰酶HDAC 1的密切同源物。与其他玉米脱乙酰酶HD 1A和核仁HD2不同，HD 1B与视网膜母细胞瘤相关蛋白Rbap 46相关的蛋白质共纯化为复合物。两种HD 1B mRNA的物种可以检测到RNA印迹，编码蛋白质的58 kDa（HD 1B-I）和51 kDa（HD 1B-II）。HD 1B-I（zmRpd 3）代表从RNA和免疫印迹判断的主要酶形式。HD 1B-I和-II mRNA的表达水平在早期胚胎萌发过程中不同; HD 1B-I mRNA和蛋白质存在于整个萌发途径中，即使在静止胚胎中，而HD 1B-II表达开始于分生组织细胞进入细胞周期的S期。与先前的结果一致，HD 1B以可溶性和染色质结合的酶形式存在。用脱乙酰酶抑制剂HC毒素体内处理分生组织不影响三种玉米组蛋白脱乙酰酶的表达，而它引起组蛋白乙酰转移酶B的下调。
Posttranslational core histone acetylation is established and maintained by histone acetyltransferases and deacetylases. Both have been identified as important transcriptional regulators in various eukaryotic systems. In contrast to nonplant systems where only RPD3-related histone deacetylases (HD) have been characterized so far, maize embryos contain three unrelated families of deacetylases (HD1A, HD1B, and HD2). Purification, cDNA cloning, and immunological studies identified the two maize histone deacetylase HD1B forms as close homologues of the RPD3-type deacetylase HDAC1. Unlike the other maize deacetylases, HD1A and nucleolar HD2, HD1B copurified as a complex with a protein related to the retinoblastoma-associated protein, Rbap46. Two HD1B mRNA species could be detected on RNA blots, encoding proteins of 58 kDa (HD1B-I) and 51 kDa (HD1B-II). HD1B-I (zmRpd3) represents the major enzyme form as judged from RNA and immunoblots. Levels of expression of HD1B-I and -II mRNA differ during early embryo germination; HD1B-I mRNA and protein are present during the entire germination pathway, even in the quiescent embryo, whereas HD1B-II expression starts when meristematic cells enter S-phase of the cell cycle. In line with previous results, HD1B exists as soluble and chromatin-bound enzyme forms. In vivo treatment of meristematic tissue with the deacetylase inhibitor HC toxin does not affect the expression of the three maize histone deacetylases, whereas it causes downregulation of histone acetyltransferase B.