Cirbp在斑马鱼低温适应中的作用与机制研究

RNA-binding protein (Cirp/Cirbp) functions as a RNA chaperone in cells. Cirbp can be markedly induced in multiple animal cell lines and tissues upon cold exposure and thus becomes a responsive marker for cold stress. However, it remains unclear about regulatory mechanisms underlying the transcription of Cirbp gene and functions of Cirbp in cold acclimation. We have previously found that zebrafish Cirbp gene possesses 6 transcript variants and transient overexpression of 3 transcript variants can improve the cold tolerance of zebrafish embryos. This project aims to further investigate Cirbp functions and transcriptional regulation of cirbp gene in zebrafish. Main contents of this project include: 1) dissect the responses of Cirbp isoforms to cold stress and their roles in cold tolerance of cells and zebrafish; 2) identify target genes, RNA binding elements and interacting proteins of Cirbp by using RNA-seq, CLIP-seq and mass-based proteomics techniques; 3) characterize cold-inducible elements in the promoter region of Cirbp gene and trans-factors modulating its alternative splicing. The approval and successful implementation of this project will elucidate functions of Cirbp in fish cold acclimation and molecular mechanisms underlying the induction of Cirbp under cold exposure, which will lay the theoretical foundation for revealing the regulatory mechanisms and intracellular signal transduction networks of fish cold tolerance.

RNA结合蛋白Cirbp是细胞内的一个RNA伴侣。低温刺激可显著诱导Cirbp在多种动物细胞系和活体组织中表达，因而成为低温刺激反应的标记。然而，迄今尚不清楚Cirbp的表达调控及其在动物低温适应中的作用与机制。我们的前期研究发现，斑马鱼Cirbp基因具有6个可变剪接体，其中3个的过表达可增强斑马鱼胚胎的低温耐受能力。本项目将深入研究斑马鱼Cirbp的功能及其基因的转录调控，主要内容包括：1）在细胞和活体水平，研究不同Cirbp亚型的低温响应及其在低温耐受中的作用；2）利用RNA-seq、CLIP-seq和质谱技术，鉴定Cirbp调控的基因、RNA结合元件和相互作用蛋白；3）鉴定Cirbp基因启动调控区的低温诱导元件和调控可变剪接的反式作用因子。本项目的获准与顺利实施，将阐明Cirbp在鱼类低温适应中的作用和受低温诱导的分子机制，为揭示鱼类低温耐受调控机制和细胞内信号传导网路奠定理论基础。