Evolution of legume seed storage proteins--a domain common to legumins and vicilins is duplicated in vicilins.
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.
Gibbs
P E
PE
Department of Biochemistry, University of California, Riverside 92521.
Strongin
K B
KB
McPherson
A
A
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
D010940:Plant Proteins; D014674:Plant Proteins, Dietary; D055314:Seed Storage Proteins; D000097793:Legumins; C006882:canavalin protein, Canavalia ensiformis; C015575:vicilin protein, plant