title: Evolution of legume seed storage proteins--a domain common to legumins and vicilins is duplicated in vicilins.
abstract: We examined the primary sequence of canavalin, the major storage protein of jack beans, and found that an ancient sequence duplication accounts for 80% of the amino acid residues. Evidence for such a duplication was also found in the orthologous proteins phaseolin and pea vicilin. This sequence duplication presumably accounts for a structural duplication in the canavalin monomer observed by crystallographic analysis. One copy of this repeat was found in a second storage-protein family, the legumins, where it encompasses almost the entire B-chain of the mature molecule. We propose that the vicilin and legumin families of legume seed proteins evolved from a common precursor, which consisted of one copy of the repeat in the vicilins.
authors.affiliation: Department of Biochemistry, University of California, Riverside 92521.
authors.forename: P E
authors.initials: PE
authors.lastname: Gibbs
authors.forename: K B
authors.initials: KB
authors.lastname: Strongin
authors.forename: A
authors.initials: A
authors.lastname: McPherson
mesh_terms: D000595:Amino Acid Sequence; D007887:Fabaceae / Q000235:genetics*; D005796:Genes; D008969:Molecular Sequence Data; D005810:Multigene Family; D010940:Plant Proteins / Q000235:genetics*; D014674:Plant Proteins, Dietary / Q000235:genetics*; D010946:Plants, Medicinal; D055314:Seed Storage Proteins; D012639:Seeds; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity; D000097793:Legumins
chemical_list: D010940:Plant Proteins; D014674:Plant Proteins, Dietary; D055314:Seed Storage Proteins; D000097793:Legumins; C006882:canavalin protein, Canavalia ensiformis; C015575:vicilin protein, plant