NUCLEAR ROLE OF YEAST POLY(A)-BINDING PROTEIN

酵母多聚 (A) 结合蛋白的核作用

• 批准号: 6387123
• 负责人: Allan S Jacobson
• 金额: $ 31.39万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-01 至 2004-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6387123
• 关键词: RNA binding protein; Saccharomyces cerevisiae; enzyme activity; fungal genetics; fungal proteins; gene interaction; messenger RNA; microarray technology; monoclonal antibody; nucleic acid probes; phenotype; polyadenylate; suppressor mutations; yeast two hybrid system

DESCRIPTION (Adapted from applicant's abstract): The proposed research seeks to understand the diverse functions of the poly(A)-binding protein that is associated with the poly(A) tail of most eukaryotic mRNAs. There is ample evidence indicating that the presence of the poly(A) tail and its bound protein has profound consequences on the expression of genes. This RNA/protein complex stimulates initiation of translation and promotes mRNA stabilization in the cytoplasm. In the nucleus, poly(A)-binding protein is required for mRNA 3'-end formation and export of the nascent mRNA from to the cytoplasm. This proposal, using the yeast Saccharomyces cerevisiae as a model system, addresses the nuclear functions of poly(A)-binding protein (Pab1p). Factors have been identified that, in concert with Pab1p, regulate the extent of polyadenylation. If the gene encoding the most well-characterized of these factors, PBP1, is disrupted, there is a substantial reduction in the lengths of poly(A) tails synthesized in cell-free extracts and inhibits the in vivo utilization of an early polyadenylation site in a HIS4 reporter. Disruption of PBP1 also suppresses the lethality of a PAB1 deletion without directly effecting mRNA stability or translation, which stands in contrast to the phenotypes of previously isolated pab1 suppressors. Two-hybrid analyses suggest that Pbp1p may be one of several regulatory factors recruited to the RNA processing apparatus. To study the role of Pbp1 and related factors in the regulation of Pab1p's function in 3'-end processing the PI proposes to: 1) analyze the biochemical activities of Pbp1p and the other Pbps, including an assessment of Pbp1p's ability to regulate the activity of poly(A) nuclease or poly(A) polymerase; 2) identify mRNAs whose expression is dependent on the relative extent of polyadenylation using oligonucleotide probe arrays; and 3) analyze the genetic relationships of PAB1 and PBP1 by determining their interactions with other genes encoding cleavage and/or polyadenylation factors by characterizing high copy suppressors of the growth defects resulting from overexpression of these genes.

描述（根据申请人的摘要改编）：拟议的研究试图 了解poly（a）结合蛋白的各种功能 与大多数真核mRNA的聚（A）尾巴相关。有很多 证据表明poly（a）尾巴的存在及其结合蛋白 对基因的表达产生了深远的影响。该RNA/蛋白质复合物 刺激翻译的启动并促进mRNA稳定 细胞质。在细胞核中，mRNA 3'-end需要poly（a）结合蛋白 从细胞质形成和出口新生mRNA。这个建议， 将酿酒酵母用作模型系统的酵母菌 聚（A）结合蛋白（PAB1P）的核功能。因素已经过去了 确定，与PAB1P一致调节多腺苷酸的程度。 如果编码这些因素最适合特征的基因，PBP1是 被破坏了，聚（a）尾巴的长度大大减少 在无细胞提取物中合成并抑制体内利用 HIS4记者中的早期聚腺苷酸化位点。 PBP1也破坏 抑制PAB1缺失的致死性，而无需直接影响mRNA 稳定性或翻译，与表型形成对比 以前隔离的PAB1抑制剂。两个杂交分析表明PBP1P 可能是招募到RNA处理的几个调节因素之一 设备。研究PBP1和相关因素在调节中的作用 PI在3'-End处理中的PI的功能PI提出的提议：1）分析 PBP1P和其他PBP的生化活动，包括评估 PBP1P调节聚（a）核酸酶或poly（a）活性的能力 聚合酶； 2）确定表达取决于相对的mRNA 使用寡核苷酸探针阵列的聚腺苷酸化程度； 3）分析 PAB1和PBP1的遗传关系通过确定其相互作用 与编码裂解和/或聚腺苷酸化因子的其他基因通过 表征由 这些基因的过表达。