A novel patatin-like gene stimulated by drought stress encodes a galactolipid acyl hydrolase

A cDNA (Vupat1) encoding a predicted 43 kDa protein mas isolated from droug ht-stressed cowpea (Vigna unguiculata) leaves. It has homology with patatin , a potato tuber storage protein with lipolytic acyl hydrolase activity, Th e recombinant protein VUPAT1 expressed in the baculovirus system displays p referentially galactolipid acyl hydrolase activity. Phospholipids are very slowly hydrolyzed and apparently triacylglycerols are not deacylated. Vupat 1 promoter contains putative drought-inducible sequences. Northern blots sh owed that gene expression is stimulated by drought stress and is more prono unced in a drought-sensitive cultivar than in a drought-tolerant one. An in volvement in drought-induced galactolipid degradation is proposed for VUPAT 1. (C) 2001 Federation of European Biochemical Societies. Published bg Else vier Science B.V. All rights reserved.