Gamma-zeins are essential for endosperm modification in quality protein maize.

ABSTRACT: Essential amino acids like lysine and tryptophan are deficient in corn meal because of the abundance of zein storage proteins that lack these amino acids. A natural mutant, opaque 2 (o2) causes reduction of zeins, an increase of nonzein proteins, and as a consequence, a doubling of lysine levels. However, o2's soft inferior kernels precluded its commercial use. Breeders subsequently overcame kernel softness, selecting several quantitative loci (QTLs), called o2 modifiers, without losing the high-lysine trait. These maize lines are known as "quality protein maize" (QPM). One of the QTLs is linked to the 27-kDa gamma-zein locus on chromosome 7S. Moreover, QPM lines have 2- to 3-fold higher levels of the 27-kDa gamma-zein, but the physiological significance of this increase is not known. Beca

SUBMITTER: Wu Y 

PROVIDER: S-EPMC2919962 | biostudies-literature | 2010 Jul

REPOSITORIES: biostudies-literature