Western Blot Analysis of Cereal Grain Prolamins Using an Antibody to Carboxyl-Linked Indoleacetic Acid

Abstract

A monoclonal antibody raised against carboxyl-linked IAA was used in Western blot analysis of storage proteins from kernels of Avena sativa, Pennisetum americanum, Sorghum bicolor, and Zea mays. IAA or an IAA-like molecule is associated with the ethanolsoluble protein fraction of the seed. Western blotting of commercial zein, the major storage protein of maize, along with physicochemical evidence reported by Leverone et al. ([1991] Plant Physiol, 96: 1070-1075) indicated that IAA is linked with this prolamin. Results suggest that an IAA-prolamin association may be widespread throughout the Poaceae.