细菌光调控基因表达元件的分子设计

项目名称： 细菌光调控基因表达元件的分子设计

项目编号： No.21202052

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 有机化学

项目作者： 邓明刚

作者单位： 华中农业大学

项目金额： 25万元

中文摘要： 藻红蓝蛋白α-亚基（α-PEC）具有可逆光致变色，能产生两个结构不同的光稳态，P566（最大吸收在566 nm）和P507（最大吸收在507 nm）。本课题拟采用SELEX技术筛选可选择性结合α-PEC不同光稳态的RNA适配子，将筛选到的RNA适配子整合于靶基因mRNA的 5'UTR，通过光调控α-PEC不同光状态，导致α-PEC与靶基因mRNA的5'UTR可逆的结合或解离，进而影响核糖体与靶基因mRNA的结合，从而实现用光调控靶基因的表达。这些光调控分子元件在RNA水平上能光调控靶基因的表达，可以为光调控生命过程提供新的光调控分子元件，并与现有的一些在蛋白质功能水平和DNA转录水平的光调控分子元件一起，组成更加完善的生命活动分子操纵的工具库。该研究对人为光调控生命过程具有重要意义。

中文关键词： 向光素；LOV结构域；汞离子检测；蛋白酶；G-四链体

英文摘要： Phycoerythrocyanin α-subunit (α-PEC) is highly photochromic under irradiation of 500 nm or 570 nm light, to yield two photo-states: P566 of maximal absorption at 566 nm, P507 of maximal absorption at 507 nm. We plan to screen RNA aptamers, which can selectively bind the photo-states of α-PEC, by use of Systematic Evolution of Ligands by EXponential Enrichment (SELEX). When the screened aptamers are ligated with the 5'UTR of mRNA of the target gene, the association or dissociation of mRNA of the target gene with ribosomes will be determined by the association or dissociation of the photo-states of alpha-PEC with the 5'UTR of mRNA of the target gene, which is photoregulated by the irradiation of 500 nm or 570 nm light. As a result, a new kind of photoregulator will be molecularly designed, which can control the expression of target genes by the lights that induce the photochromism of α-PEC. The new kind of photoregulators work at RNA level, together with the photoregulators at DNA level and at protein level, will more fully equip our molecular tools to engineer the regulations of cells. It is important for us to manipulate the biological processes via lights.

英文关键词： phototropin；LOV domain；Hg(II) detection；proteases；g-quadruplex