MOLECULAR-CLONING AND CHARACTERIZATION OF A GIBBERELLIN-INDUCIBLE, PUTATIVE ALPHA-GLUCOSIDASE GENE FROM BARLEY

A putative alpha-glucosidase clone has been isolated from a cDNA libra ry constructed from mRNA of barley aleurones treated with gibberellin A(3) (GA). The clone is 2752 bp in length and has an uninterrupted ope n reading frame encoding a polypeptide of 877 amino acids. A 680 amino acid region is 43% identical to human lysosomal alpha-glucosidase and other glycosyl hydrolases. In isolated aleurones, the levels of the c orresponding mRNA increase strongly after the application of GA, simil ar to the pattern exhibited by low-pI alpha-amylase mRNA. High Levels are also observed in the aleurone and scutellum after germination, whi le low levels are found in developing seeds. The genome contains a sin gle form of this ol-glucosidase gene and two additional sequences that may be related genes or pseudogenes.