Genome-wide analysis and environmental response profiling of SOT family genes in rice (Oryza sativa)

Sulphotransferase (SOT) catalyses the transfer of a sulphonate group from 3'-phosphoadenosine 5'-phosphosulphate (PAPS) to an appropriate hydroxyl group of various substrates with the parallel formation of 3'-phosphoadenosine 5'-phosphate (PAP). Although several SOTs have been identified and characterized in mammalian, their role in plant is still unclear. In this study, we report genome-wide comprehensive expression analysis of 35 putative SOT genes in rice. The 35 OsSOTs were tandemly arranged into six clusters. The phylogenetic analysis showed that there were 7 subfamilies of OsSOTs and 11 putatively conserved motifs. Six OsSOTs might be pseudogenes, 25 have the two motifs which were involved in PAPS binding regions I and IV. Microarray data indicated that all the OsSOTs were expressed almost at the same level but with different patterns: most OsSOTs were expressed exclusively in stigma and ovary and induced by IAA and BAP, several genes were induced by tZ and DMSO and 11 OsSOTs were response to abiotic stress. Further analysis showed that these 11 genes contained cis-regulatory elements responding to abiotic stresses.