Mouse RNA helicase II/Gu: cDNA and genomic sequences, chromosomal localization, and regulation of expression.
Mouse RNA helicase II/Gu: cDNA and genomic sequences, chromosomal localization, and regulation of expression.
复制标题
小鼠 RNA 解旋酶 II/Gu：cDNA 和基因组序列、染色体定位和表达调节。
DOI：
10.1006/geno.2000.6209
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Wang,W
中科院分区：
文献类型：
--
作者：
Valdez,BC;Wang,W
RNA解旋酶II/Gu(RH II/Gu)是一种哺乳动物核仁RNA解旋酶，以前用西瓜胃病患者的自身免疫血清鉴定。Rh II/Gu可以解开双链RNA，可以折叠或引入二级结构到单链RNA。这两种酶活性位于RH II/Gu分子的两个不同区域。本研究对小鼠RHⅡ/Gu的基因和基因组序列进行了分子分析，并对其染色体定位和表达调控进行了研究。该氨基酸序列在蛋白质的NH2末端有三个串联重复序列，这些序列在人类同源基因中不保守。每个重复序列含有37个富含碱性残基的氨基酸。解旋酶和折叠酶结构域在小鼠和人RH II/Gu之间高度保守。小鼠RHⅡ/Gu基因的基本启动子区域位于ATG起始密码子上游300个核苷酸以内。在这个启动子区域的上游是一个抑制小鼠RH II/Gu基因转录的沉默分子。这个抑制区包含三个串联的38核苷酸重复序列。小鼠RHⅡ/Gu由14个外显子和13个内含子组成。该基因的3‘侧翼序列含有3个可能的多聚腺苷酸化位点，但经Northern印迹分析和EST数据库中小鼠RH II/Gu基因的3’端序列分析，仅有2个位点可能具有功能。这两个可供选择的多聚腺苷酸化位点大约是TGA终止密码子的240和2100个核苷酸。小鼠和人类的RH II/Gu基因都定位在10号染色体上。小鼠RH II/Gu基因的获得将有助于其功能分析，包括创造一个RH II/Gu蛋白缺失的小鼠。
RNA helicase II/Gu (RH II/Gu) is a mammalian nucleolar RNA helicase previously identified using an autoimmune serum from a patient with watermelon stomach disease. RH II/Gu can unwind double-stranded RNA and can fold or introduce a secondary structure to a single-stranded RNA. These two enzymatic activities reside in two separate domains of the RH II/Gu molecule. The present study reports the molecular analysis of the cDNA and genomic sequences of the mouse RH II/Gu, its chromosomal localization, and the regulation of expression. The cDNA-derived amino acid sequence shows three tandem repeats at the NH2-terminal end of the protein, which are not conserved in the human homologue. Each repeat has 37 amino acids that are rich in basic residues. The helicase and foldase domains are highly conserved between the mouse and the human RH II/Gu. The basic promoter region of the mouse RH II/Gu gene is within 300 nucleotides upstream of a putative ATG initiation codon. Upstream of this promoter region is a silencer that represses transcription of the mouse RH II/Gu gene. This inhibitory region contains three 38-nucleotide repeats in tandem. The mouse RH II/Gu consists of 14 exons and 13 introns. The 3′ flanking sequence of the gene contains three putative polyadenylation sites but only two sites are probably functional as shown by Northern blot analysis and 3′ end sequences of mouse RH II/Gu cDNA in the EST database. These two alternative polyadenylation sites are approximately 240 and 2100 nucleotides from the TGA stop codon. Both mouse and human RH II/Gu genes are localized on chromosome 10. The availability of the mouse RH II/Gu gene will facilitate its functional analysis including creation of a mouse deficient in RH II/Gu protein.