| dc.description.abstract | Plants cannot move under environmental stress so they use subsequent protein expression through rapid gene regulation, thereby changing their physiological state to achieve the purpose of adapting to environmental stress. mRNA is an important part of gene expression, and its quantity is regulated by the transcriptional and post-transcriptional level. In eukaryotes, mRNA deadenylation is the first step in the degradation of most mRNAs, and it is also a rate-determining step. In this step, deadenylase will short the length of poly(A) tail to make the mRNA unstable and easily to be degraded and then reduce the efficiency of translation, which ultimately affects protein content. The CCR4-NOT complex plays an important role in mRNA deadenylation, which utilizes two deadenylases, carbon catabolite repressor 4 (CCR4) and CAF1 (CCR4-associated factor 1), to participate in the mechanism of mRNA degradation. Rice contains 4 CAF1 genes, among which OsCAF1H will greatly increase the expression when rice is exposed to heat stress. Therefore, this study will further explore the function of rice CAF1H under heat stress in rice.
Through GUS activity analysis and histochemical staining experiments, we knew that the rice CAF1H gene is a heat-inducible gene, and according to the promoter sequence alignment analysis, we found that rice CAF1H contained an atypical heat shock element (HSE) sequence. According to the germination rate test and the survival rate test, the CAF1H overexpression lines show better tolerance to heat stress compare with WT and CAF1H knock out lines. According to the results of RNA-seq analysis, we found that the expression of Histone 2A was significantly decreased in wild-type after heat stress, but there was no significant difference in the OsCAF1H knockout transgenic lines. It is speculated that Histone 2A may be one of the downstream target genes of OsCAF1H. | en_US |