Identification of two new genes from drought tolerant peanut up-regulated in response to drought

Using differential display of mRNA transcripts, we obtained nine partial cDNA clones that were up-regulated and down-regulated by exposure to drought. Two full length cDNAs of 825 bp and 700 bp, designated as Arachis hypogaea serine rich protein (AhSrp) and Arachis hypogaea leucine rich protein (AhLrp) were obtained using RLM-RACE. Based on the cDNA sequence, the transcriptional start site of AhSrp and AhLrp was assigned. AhSrp is predicted to code for a protein of 233 amino acids containing a signal peptide, three potential transmembrane domains and a sumolyation motif. AhLrp is predicted to code for a protein of 206 amino acids containing a signal peptide. The expression of partial cDNA and full-length cDNA were confirmed by RNA dot blot analysis. Expression of AhSrp was observed between 6 and 10 days of stress and prominent expression of AhLrp was visualized at 10 days of stress by semi quanititative PCR. Our studies have resulted in the identification of two new genes that may play a role in plant response to drought stress in peanut. © 2007 Springer Science+Business Media B.V