Identification and characterization of a novel abiotic stress responsive sulphotransferase gene (OsSOT9) from rice

Abiotic stresses may seriously affect plant growth and development. In order to explore new stress tolerance genes in rice (Oryza sativa L.), expression profiles were obtained for leaf and panicle tissues. They were taken at seedling, booting, heading and flowering stages of indica cultivar Pei'ai 64S plants under cold, drought and heat stresses by using the GeneChip Rice Genome Array (Affymetrix), which includes 51,279 transcripts from japonica and indica rice. O. sativa L. cytosolic sulphotransferase-like gene (OsSOT9) was highly induced in leafs and panicles during different developmental stages, in response to all stresses, especially at booting stage under cold stress. The quantitative real-time polymerase chain reaction analysis showed that this result was almost consensus with GeneChip Rice Genome Array. cDNA of OsSOT9 was cloned to study its function in stress tolerance through reverse transcription PCR. Sequence analysis showed that the cDNA encoded a protein with molecular weight of about 37.78 kDa and pl of about 6.6, which was composed of 343 amino acid residues. Bioinformatics data showed that the protein contained a conservative domain of the sulphotransferase (SOT) family gene. OsSOT9 was found to be closely related to the cytosolic sulphotransferase after comparison of the protein sequences. Analysis of the putative promoter region found 12 kinds of cis-elements related to stress response. On the basis of the above analyses, we suggested that OsSOT9 is a novel candidate gene involved in stress tolerance in rice.