Expression and subcellular localization of antiporter regulating protein OsARP in rice induced by submergence, salt and drought stresses

Abstract

We examined the expression and subcellular localization of antiporter regulating protein OsARP in a submergence tolerant rice (Oryza sativa L.) cultivar FR13A. In the public databases, this protein was designated as putative Os02g0465900 protein. The cDNA containing the full-length sequence of OsARP gene was present in Gene Bank Accession no. AK071205 and this encoded 216 amino acids which had molecular mass of 25 kD. The OsARP gene was first expressed into E. coli and antibody was produced by using purified recombinant protein. The expression of OsARP protein was detected under submergence, salt and drought stresses. This protein was widely expressed in roots, shoots and leaves of rice under salt stress. To get an insight into the functional role of OsARP protein, subcellular localization was done using cell fractionation of rice leaves. Immuno-blotting of 3-day submergence rice leaves cell fractions detected the presence of OsARP protein in plasma-membrane fraction only. This indicates that OsARP is a membrane bound protein of rice which is expressed under submergence, salt and drought stresses.

Key words: Drought, antiporter regulating protein, immuno-localization, rice, salinity, submergence.