title: Enzymatic control of anthocyanin expression in the flowers of pea (Pisum sativum) mutants.
abstract: Using enzymological and immunological methods we have investigated the relationship between chalcone synthase and the A locus, a major gene involved in the control of anthocyanin expression in pea (Pisum sativum L.) flowers. Pea plants containing the dominant allele A usually synthesize anthocyanins in the petal tissue, whereas plants homozygous for the a allele do not produce anthocyanins. We sought to determine whether or not the A locus also controlled the presence or absence of chalcone synthase, the first enzyme of the flavonoid pathway in the flowers of three genetic lines (A, purple-violet flowers; A,am, white flowers with sometimes pink edges; and a, white flowers). Chalcone synthase was found to be present in all three genetic lines by enzyme activity measurement, indirect enzyme-linked immunosorbent assay (ELISA), and Western blotting. Spectroscopic investigations showed that only the genetic lines A and A,am contained anthocyanins and flavonol glycosides, respectively, in the flowers; line a accumulated p-coumaric acid or its derivatives. These data suggest that the A locus in Pisum is not the structural gene for chalcone synthase and it does not appear to regulate the expression of this enzyme.
mesh_terms: D000217:Acyltransferases / Q000235:genetics*; D000872:Anthocyanins / Q000032:analysis / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005796:Genes; D009154:Mutation; D010944:Plants / Q000235:genetics* / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D000217:Acyltransferases; C020141:flavanone synthetase