Distinct effects of PTST2b and MRC on starch granule morphogenesis in potato tubers.

The molecular mechanisms underpinning the formation of the large, ellipsoidal starch granules of potato tuber are poorly understood. Here, we demonstrate the distinct effects of PROTEIN TARGETING TO STARCH2b (PTST2b) and MYOSIN RESEMBLING CHLOROPLAST PROTEIN (MRC) on tuber starch granule morphology. A gene duplication event in the Solanaceae resulted in two PTST2 paralogs (PTST2a and PTST2b).

Reducing amylose content in wheat (Triticum aestivum L.) using a novel Wx-D1 null allele generated by chemical mutagenesis.

Background: Amylose has a major influence over starch properties and end-use quality in wheat. The granule-bound starch synthase I, encoded by Wx-1, is the single enzyme responsible for amylose synthesis. Natural null mutants of Wx-1 appear at extremely low frequencies, particularly in the Wx-D1 locus, where only four spontaneous null variants have been identified, with different geographic origins.

Nuclear factor-Y-polycomb repressive complex2 dynamically orchestrates starch and seed storage protein biosynthesis in wheat.

The endosperm in cereal grains is instrumental in determining grain yield and seed quality, as it controls starch and seed storage protein (SSP) production. In this study, we identified a specific nuclear factor-Y (NF-Y) trimeric complex in wheat (Triticum aestivum L.), consisting of TaNF-YA3-D, TaNF-YB7-B, and TaNF-YC6-B, and exhibiting robust expression within the endosperm during grain filling.

Mutations in starch BRANCHING ENZYME 2a suppress the traits caused by the loss of ISOAMYLASE1 in barley.

The hvbe2a mutations restore the starch-deficient phenotype caused by the hvisa1 and hvflo6 mutations in barley endosperm. The genetic interactions among starch biosynthesis genes can be exploited to alter starch properties, but they remain poorly understood due to the various combinations of mutations to be tested. Here, we isolated two novel barley mutants defective in starch BRANCHING ENZYME 2a (hvbe2a-1 and hvbe2a-2) based on the starch granule (SG) morphology.