Isolation and characterization of drought-induced cDNA clones from hot pepper (Capsicum annuum)

Abstract

Drought is a major environmental factor that limits plant growth and productivity. After constructing a cDNA library from progressively drought-stressed hot pepper plants (Capsicum annuum), we differentially screened it to isolate cDNA clones whose expressions were drought-inducible. We named these clonesCaDSi-1, S, 7,11, and12. RNA blot analyses revealed that all transcripts of these genes were induced strongly or slightly during progressive drought stress. Their deduced amino-add sequences showed high homologies with such proteins as thioredoxinm, gtvdne-rich protein, nonspecific lipid transfer protein, oxygen-evolving enhancer protein 3, and auxin-repressed protein. In other plant species, those proteins are induced by pathogens and water or salt stresses, and are predicted to be involved in drought tolerance. The data suggest that these fiveCaDSi gene products have possible protective roles against drought stress in hot pepper.