An ATM homologue from Arabidopsis thaliana: complete genomic organisation and expression analysis
An ATM homologue from Arabidopsis thaliana: complete genomic organisation and expression analysis
复制标题
DOI：
10.1093/nar/28.8.1692
复制
发表时间：
2000-04-15
影响因子：
14.9
通讯作者：
Tissier, Alain
中科院分区：
文献类型：
--
作者：
Garcia, Valerie;Salanoubat, Marcel;Tissier, Alain
ATM是一个在人类共济失调毛细血管扩张症中突变的基因，在酵母、果蝇、非洲爪蟾和小鼠中有报道同源物。每当突变体是可用的，它们都表明了这个基因家族在细胞对DNA损伤的反应中的作用。在这里，我们提出的第一个植物同源ATM的鉴定和分子特征。AtATM（ATM的拟南芥同源物）的基因组基因座跨度超过30 kb，并通过79个外显子的剪接转录成12 kb的mRNA。它是一个单拷贝基因，定位在3号染色体的长臂上。AtATM的转录是普遍存在的，并且不受电离辐射诱导。由AtATM编码的推定的蛋白质是3856个氨基酸长，并且包含磷脂酰肌醇-3激酶样（Pi 3 k-l）结构域和rad 3结构域，ATM家族的其他成员所共有的特征。AtAtm蛋白与Atm高度相似，在Pi 3 k-l和rad 3结构域中分别具有67%和45%的相似性。有趣的是，该蛋白的N-末端部分含有PWWP结构域，其也存在于参与DNA代谢的其他蛋白质中，例如人错配修复酶Msh 6和哺乳动物从头甲基转移酶Dnmt 3a/B。
ATM is a gene mutated in the human disease ataxia telangiectasia with reported homologues in yeast, Drosophila, Xenopus and mouse. Whenever mutants are available they all indicate a role of this gene family in the cellular response to DNA damage. Here, we present the identification and molecular characterisation of the first plant homologue of ATM. The genomic locus of AtATM (Arabidopsis thaliana homologue of ATM) spans over 30 kb and is transcribed into a 12 kb mRNA resulting from the splicing of 79 exons. It is a single copy gene and maps to the long arm of chromosome 3. Transcription of AtATM is ubiquitous and not induced by ionising radiation. The putative protein encoded by AtATM is 3856 amino acids long and contains a phosphatidyl inositol-3 kinase-like (Pi3k-l) domain and a rad3 domain, features shared by other members of the ATM family. The AtAtm protein is highly similar to Atm, with 67 and 45% similarity in the Pi3k-l and rad3 domains respectively. Interestingly, the N-terminal portion of the protein harbours a PWWP domain, which is also present in other proteins involved in DNA metabolism such as human mismatch repair enzyme Msh6 and the mammalian de novo methyl transferases, Dnmt3a/b.