title: Expression of wild-type pinB sequence in transgenic wheat complements a hard phenotype.
abstract: Wheat grain hardness is a major factor in the wheat end-product quality. Grain hardness in wheat affects such parameters as milling yield, starch damage and baking properties. A single locus determines whether wheat is hard or soft textured. This locus, termed Hardness ( Ha), resides on the short arm of chromosome 5D. Sequence alterations in the tryptophan-rich proteins puroindoline a and b (PINA and PINB) are inseparably linked to hard textured grain, but their role in endosperm texture has been controversial. Here, we show that the pinB-D1b alteration, common in hard textured wheats, can be complemented by the expression of wild-type pinB-D1a in transformed plants. Transgenic wheat seeds expressing wild-type pinB were soft in phenotype, having greatly increased friabilin levels, and greatly decreased kernel hardness and damaged starch. These results indicate that the pinB-D1b alteration is most likely the causative Ha mutation in the majority of hard wheats.
authors.affiliation: Dept. of Plant Sciences and Plant Pathology, Ag. BioSci. Fac., Montana State University, Bozeman, MT 59717-3150, USA.
authors.forename: B.
authors.initials: B
authors.lastname: Beecher
authors.forename: A.
authors.initials: A
authors.lastname: Bettge
authors.forename: E.
authors.initials: E
authors.lastname: Smidansky
authors.forename: J.
authors.initials: J
authors.lastname: Giroux