水稻snoRNA47基因簇的初步鉴定  

Identification of a snoRNA47 Gene Cluster in Oryza sativa

作　　者：江舸[1] 李伟[1] 金由辛[1] 王德宝 

机构地区：[1]中国科学院上海生命科学研究院生物化学与细胞生物学研究所分子生物学国家重点实验室,上海200031

出　　处：《生物化学与生物物理学报》2002年第5期667-670,共4页

基　　金：中国科学院"十五"科技创新项目 (No .KSCX2 2 0 4);中国科学院上海生命科学研究院资助项目

摘　　要：通过生物信息学分析 ,在水稻染色体中发现一个新的C/D框snoRNA基因簇。此基因簇含有 3个C/D框snoRNA基因 ,它们都具有典型的C框和D框保守元件 ;末端能形成茎环结构 ;含有一段相同的 1 2nt“引导”序列 ,此序列能与水稻 1 8SrRNA中第 6 2 1位到 6 32位的序列互补配对。通过实验证明 ,这 3种snoRNA的确存在于水稻细胞核内 ,并确定出它们各自 5′端的位置。进一步对此snoRNA基因簇的表达进行研究发现 ,此基因簇中的 3个snoRNA基因共同转录成为一个多顺反子的前体。将这 3种新发现的水稻snoRNA分别命名为OSsnR4 7.1 ,OSsnR4 7.2和OSsnR4 7.3。编码它们的基因已被GenBank收录 ,其登录号分别为 :AF4 5 35 0 4 ,AF4 5 35 0 3和AF4 5 35 0Small nucleolar RNAs (snoRNAs) are required for ribose 2′ O methylation of eukaryotic ribosomal RNA. By researching in international rice genome databases, a snoRNA gene cluster, consisting of three box C/D snoRNA gene candidates, was found on chromosome 6. All of snoRNA coding sequences in this cluster exhibited the characteristic structure of box C/D antisense snoRNA. They shared conserved box C and box D motifs, a stable terminal stem formed by a 4—6 nt long inverted repetition sequence located upstream of box C and downstream of box D. All candidates had a 12 nt long sequence complementary to the region from 621 nt to 632 nt in rice 18 S rRNA (nt numbering according to GenBank accession No.X00755), and might mediate the ribose 2′ O methylation of A 623 in rice 18 S rRNA. Comparison of these sequences showed that these three rice snoRNAs were homologue of yeast snR47. These three rice snoRNAs were named as OSsnR47.1, OSsnR47.2 and OSsnR47.3, respectively. Primer extension assay showed that these three snoRNAs were transcribed in vivo and determined the 5′ ends of each snoRNA. RT PCR detected transcripts containing linked snoRNA47s and this suggested that the snoRNAs encoded in the cluster might be transcribed as a polycistronic transcript under the control of a single upstream promoter. The gene sequences encoding these three snoRNAs had been deposited in GenBank under accession number of AF453504, AF453503 and AF453502.

关 键 词：鉴定 C/D框snoRNA OSsnR47基因簇 RRNA 甲基化 水稻 snoRNA47基因簇 

分 类 号：Q943[生物学—植物学]