Isolation and characterization of a novel s-adenosyl-l-methionine synthetase cDNA from rice (Oryza satival l cv Pusa Basmati 1)

Abstract

An expression assay of randomly selected cDNAs resulted in the isolation of a novel cDNA (OSISAM) of SAM synthetase from rice. Nucleotide sequence data show that the cDNA is similar to a genomic clone (pRSAM1) from rice in the coding region but differs in the 5' untranslated region (UTR) that is unique to this cDNA. The RNase protection experiments and search of EST database confirmed the presence of such novel cDNA. Northern analysis shows that the gene is differentially expressed in various tissues. The transcript abundance also increases when plants are stressed with salt, drought, ABA, injury, osmotic- or heat-shock, but it is not influenced by cold stress.