title: Selective proteolysis of the wheat Em polypeptide. Identification of an endopeptidase activity in germinating wheat embryos.
abstract: The 'Em' polypeptide is the most abundant cytosolic polypeptide in mature wheat embryos. It is selectively and completely degraded within the first 24 h of germination. Extracts from germinated embryos contain endopeptidase activities which degrade the Em polypeptide. These are separable into a major and minor component by ion-exchange chromatography and the use of inhibitors shows the major component to be a cysteine proteinase. This activity shows a strong preference for the Em polypeptide as a substrate, being inactive against polypeptides which are not developmentally regulated and showing only low activity towards developmentally related, but otherwise nonhomologous 'dehydrin' polypeptides.
authors.affiliation: Department of Genetics, Leeds University, UK.
authors.forename: R M
authors.initials: RM
authors.lastname: Taylor
authors.forename: A C
authors.initials: AC
authors.lastname: Cuming
mesh_terms: D003546:Cysteine Endopeptidases / Q000378:metabolism*; D006868:Hydrolysis; D010940:Plant Proteins / Q000378:metabolism*; D011480:Protease Inhibitors / Q000494:pharmacology; D012639:Seeds / Q000201:enzymology; D014908:Triticum / Q000201:enzymology / Q000378:metabolism*
chemical_list: C073988:Em protein, Triticum aestivum; D010940:Plant Proteins; D011480:Protease Inhibitors; D003546:Cysteine Endopeptidases