Mehta Saurabh Jayesh Kumar, Joshi Pradyumna A, Mishra Ram Kumar
Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal, India.
Bio Protoc. 2021 Feb 20;11(4):e3924. doi: 10.21769/BioProtoc.3924.
Loss of function studies shed significant light on the involvement of a gene or gene product in different cellular processes. Short hairpin RNA (shRNA) mediated RNA interference (RNAi) is a classical yet straightforward technique frequently used to knock down a gene for assessing its function. Similar perturbations in gene expression can be achieved by siRNA, microRNA, or CRISPR-Cas9 methods also. In genetics, the UAS-GAL4 system is utilized to express RNAi and make ubiquitous and tissue-specific knockdowns possible. The UAS-GAL4 system borrows genetic components of , hence rule out the possibility of accidental expression of the system. In particular, this technique uses a target-specific shRNA, and the expression of the same is governed by the upstream activating sequence (UAS). Controlled expression of GAL4, regulated by specific promoters, can drive the interfering RNA expression ubiquitously or in a tissue-specific manner. The knockdown efficiency is measured by RNA isolation and semiquantitative RT-PCR reaction followed by agarose gel electrophoresis. We have employed immunostaining procedure also to assess knockdown efficiency. RNAi provides researchers with an option to decrease the gene product levels (equivalent to hypomorph condition) and study the outcomes. UAS-GAL4 based RNAi method provides spatio-temporal regulation of gene expression and helps deduce the function of a gene required during early developmental stages also.
功能缺失研究为基因或基因产物参与不同细胞过程提供了重要线索。短发夹RNA(shRNA)介导的RNA干扰(RNAi)是一种经典且直接的技术,常用于敲低基因以评估其功能。通过siRNA、微小RNA或CRISPR-Cas9方法也可以实现类似的基因表达扰动。在遗传学中,UAS-GAL4系统用于表达RNAi,使全身性和组织特异性敲低成为可能。UAS-GAL4系统借用了[此处原文缺失相关内容]的遗传元件,因此排除了该系统意外表达的可能性。特别地,该技术使用靶标特异性shRNA,其表达受上游激活序列(UAS)控制。由特定启动子调控的GAL4的可控表达可以驱动干扰RNA全身性或组织特异性表达。通过RNA分离和半定量RT-PCR反应,随后进行琼脂糖凝胶电泳来测量敲低效率。我们也采用免疫染色程序来评估敲低效率。RNAi为研究人员提供了一种降低基因产物水平(等同于亚效等位基因状态)并研究结果的选择。基于UAS-GAL4的RNAi方法提供了基因表达的时空调控,也有助于推断早期发育阶段所需基因的功能。