Distinct Functions of STARCH SYNTHASE 4 Domains in Starch Granule 13 Formation 1 14 Kuan -

Distinct Functions of STARCH SYNTHASE 4 Domains in Starch Granule 13 Formation 1 14

Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion

Arabidopsis thaliana mutants lacking the SS4 isoform of starch synthase have strongly reduced numbers of starch granules per chloroplast, suggesting that SS4 is necessary for the normal generation of starch granules. To establish whether it plays a direct role in this process, we investigated the circumstances in which granules are formed in ss4 mutants. Starch granule numbers and distribution ...

Degradation of Glucan Primers in the Absence of Starch Synthase 4 Disrupts Starch Granule Initiation in Arabidopsis*

Arabidopsis leaf chloroplasts typically contain five to seven semicrystalline starch granules. It is not understood how the synthesis of each granule is initiated or how starch granule number is determined within each chloroplast. An Arabidopsis mutant lacking the glucosyl-transferase, STARCH SYNTHASE 4 (SS4) is impaired in its ability to initiate starch granules; its chloroplasts rarely contai...

Comparative proteome analysis of A- and B-type starch granule-associated proteins in bread wheat (Triticum aestivum L.) and Aegilops crassa.

UNLABELLED Starch is the main component in the wheat endosperm and exists in two forms including A- and B-type granules. A bread wheat line CB037A and an Aegilops line Aegilops crassa were studied for the underlying starch biosynthesis mechanism in relation to granule types. The wheat line contains both types of starch granules while the Aegilops line only has the A-type. Differential starch gr...

Regulation of starch accumulation by granule-associated plant 14-3-3 proteins.

In higher plants the production of starch is orchestrated by chloroplast-localized biosynthetic enzymes, namely starch synthases, ADP-glucose pyrophosphorylase, and starch branching and debranching enzymes. Diurnal regulation of these enzymes, as well as starch-degrading enzymes, influences both the levels and composition of starch, and is dependent in some instances upon phosphorylation-linked...