ISSN:
1432-2242
Keywords:
cDNA
;
Legumin subunits
;
Polymorphism
;
Gene assignment
;
Vicia faba
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Legumin, which amounts to approximately 55% of the seed protein in field beans (Vicia faba L. var. minor), is a representative of the 12S storage globulin family. The 12S storage globulins are hexameric holoprotein molecules composed of different types of polymorphic subunits encoded by a multigene family. ‘Type-A’ legumin subunits contain methionine whereas ‘type-B’ are methionine-free subunits. Sequencing of two different type A-specific cDNAs, as well as an FPLC/HPLC-based improvement of subunit fractionation and peptide mapping with subsequent partial amino-acid sequencing, permit the assignment of some of the polymorphic legumin subunits to members of the multigene family. Two different type A subunits (A1 and A2) correspond to the two different cDNA clones pVfLa129 (A2) and 165 (A1), but microheterogeneity in the amino-acid sequences indicates that polymorphic variants of both representatives of this type may exist. Two groups of published type B-specific gene sequences (LeB7, and LeB2, LeB4, LeB6, respectively) are represented by two polymorphic subunit fractions (B3I, B3II, and B4I, B4II). A seventh clone, LeB3, encodes one of the large legumin subunits that is only a minor component of the legumin seed protein complex.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00212614
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