Analysis Of Proteome Of The Salt-tolerant Mutant Involved In Salt-stress And Cloning Of The Salt-stress Related Genes

In the study, two dimensional electrophoresis (2-DE) and MS was used to analyse the proteome of the salt-tolerant mutant of wheat (RH8706-49) and the salt-sensitive mutant of wheat (H8706-34). When pH 3-10 IPG strips is applied in 2-DE, 5 candidate proteins are identified expressed differently in gel between RH8706-49 and H8706-34. After being analysised by MALDI-TOF-MS and Mascot software, the five candidate proteins were identified : H+-transporting two-sector ATPase, glutamine synthetase 2 precursor, putative 33 kDa oxygen evolvingprotein of photosystem II and ribulose-l,5-bisphosphate carboxylase/oxygenase small subunit.These five proteins are all chloroplast protein, in which glutamine synthetase 2 precursor and OEC33 (putative 33 kDa oxygen evolvingprotein of photosystem II ) can not be found in H8706-34. H+-transporting two-sector ATPase is differently modified suggested that the possible mutation of allele.In addition, ribulose-l,5-bisphosphate carboxylase/oxygenase small subunit is down-regulated in H8706-34 under stress. Using the same protocol , the root proteome is compared between RH8706-49 and H8706-34. It was found a large quantity of proteins down-regulated in H8706-34 treated with 1% NaCl 3h. There are 22 candidate protein spots are selected for MS, in which 2 spots are identified as the same protein: Vacuolar proton-ATPase subunit A.The other proteins are unmatched to known proteins in the database. A cDNA fragment of vacuolar proton-ATPase subunit A is obtained by 3'RACE (rapid amplication cDNA end). Implications of these proteins for the molecular mechanism involved in salt-tlerance are discussed.