| dc.description.abstract | Small heat shock proteins represent the most abundant heat shock proteins in plants. These proteins have chaperon activity, which can prevent cellular proteins from thermal-induced irreversible denaturation under heat stress. By the proteomic approach, we found that OsHSP101 is a potential candidate interacting with OsHSP16.9A during high temperature. In addition, our previous study found the abundance of OsHSP16.9A and OsHSP101 was in the embryo and vanished after imbibition for two days. To clear up the interplay between OsHSP16.9A and OsHSP101, we used ratiometric bimolecular fluorescence complementation (rBiFC) to investigate the interaction between OsHSP16.9A and OsHSP101. The results show that OsHSP16.9A interacts with OsHSP101 under non-stress and heat stress conditions. Besides, we found that mutation of the 74th amino acid residue, Glu to Asp, of the OsHSP16.9A leads to abolish the interaction of OsHSP16.9A and OsHSP101. Our results indicate that the 74th amino acid of OsHSP16.9A is critical for OsHSP16.9A–OsHSP101 interaction under thermal stress. Besides, we also analyzed OsHSP16.9A and OsHSP101 accumulation level during seed maturation in 5 different rice cultivar, including TNG67, CO39, N22, IR50 and IR28. Accumulation levels of OsHSP16.9A and OsHSP101 showed similar patterns during seed maturation. OsHSP16.9A and OsHSP101 start to accumulate at the milk stage and reach the peak at the hard dough stage or mature stage. These results indicate that accumulation of OsHSP16.9A and OsHSP101 during seed development may be important for seeds to gain thermotolerance. When a suitable environment manifests for seed germination, OsHSP16.9A and OsHSP101 will start to decline. Therefore, we suppose there has a positive feedback loop between OsHSP16.9A and OsHSP101, which similar to OsHSA32 and OsHSP101. | en_US |