Various environmental stresses affect different growth stage and yield of the plants. Therefore, plants regulate the expression level of genes for adjusting cellular status in response to variable environment. Poly(A) tail shortening, also termed as deadenylation, is the rate-limiting step of mRNA degradation in eukaryotic cells. CCR4-associated factor 1 (CAF1) proteins are important enzymes for catalysis of mRNA deadenylation in the eukaryotes. This study investigated the role of a rice heat-induced CAF1, OsCAF1H, in the adaptation of rice plants to heat stress. Expression of OsCAF1H was closely linked with the high-temperature exposure. The expression level of OsCAF1H was increased 9.9-fold in roots and 4.2-fold in shoots after shifting to 45˚C for 1 hour, and dramatically decreased to the basal level after 3 hours of recovery at room temperature. The OsCAF1H promoter contains one canonical palindromic and one atypical Heat Shock Element. In order to investigate the OsCAF1H promoter activity, the transgenic seedlings of OsCAF1H promoter drive glucuronidase (GUS) reporter gene were generated and analysed. GUS staining was detected inshoots, roots, endosperm and embryos under heat treatment (45˚C) for 1h, 2h, 3h, and 4hours. Our data revealed that CAF1H promoter was positively regulated by heat stress in rice.
