Structure, expression and localization of a germin-like protein in barley (Hordeum vulgare L.) that is insolubilized in stressed leaves.

摘要: The primary leaves of young barley seedlings contain two major, extracellular, acid-soluble proteins ca. 22 and 23 kDa apparent molecular mass. These disappeared from the intercellular washing fluid upon stress treatments that enhanced H2O2 levels induced resistance to subsequent challenge by powdery mildew fungus Erysiphe graminis f. sp. hordei. A partial peptide sequence protein was determined, a cDNA clone isolated. belongs group germin-like (GLPs) designated HvGLP1. Despite its similarity germin, i.e. oxalate oxidase, no oxidase activity HvGLP1 could be detected. RNA soluble highly abundant in leaves, less older absent roots. oscillated with circadian rhythm, minimum maximum abundance being at end dark light periods, respectively. Heat treatment as well pathogen infection caused disappearance fraction space. re-solubilized cell walls heat- or H2O2-treated boiling SDS suggesting non-covalent cross linking. Although physiological role insolubilization is still open, may serve marker for oxidative cereals.