Campus Units

Biochemistry, Biophysics and Molecular Biology, Roy J. Carver Department of

Document Type

Article

Publication Version

Published Version

Publication Date

5-21-2011

Journal or Book Title

BMC Plant Biology

Volume

11

First Page

95

DOI

10.1186/1471-2229-11-95

Abstract

Background: Two distinct starch branching enzyme (SBE) isoforms predate the divergence of monocots and dicots and have been conserved in plants since then. This strongly suggests that both SBEI and SBEII provide unique selective advantages to plants. However, no phenotype for the SBEI mutation, sbe1a, had been previously observed. To explore this incongruity the objective of the present work was to characterize functional and molecular phenotypes of both sbe1a and wild-type (Wt) in the W64A maize inbred line.

Results: Endosperm starch granules from the sbe1a mutant were more resistant to digestion by pancreatic aamylase, and the sbe1a mutant starch had an altered branching pattern for amylopectin and amylose. When kernels were germinated, the sbe1a mutant was associated with shorter coleoptile length and higher residual starch content, suggesting that less efficient starch utilization may have impaired growth during germination.

Conclusions: The present report documents for the first time a molecular phenotype due to the absence of SBEI, and suggests strongly that it is associated with altered physiological function of the starch in vivo. We believe that these results provide a plausible rationale for the conservation of SBEI in plants in both monocots and dicots, as greater seedling vigor would provide an important survival advantage when resources are limited.

Comments

This article is published as Xia, Huan, Marna Yandeau-Nelson, Donald B. Thompson, and Mark J. Guiltinan. "Deficiency of maize starch-branching enzyme i results in altered starch fine structure, decreased digestibility and reduced coleoptile growth during germination." BMC plant biology 11 (2011): 95. doi: 10.1186/1471-2229-11-95. Posted with permission.

Rights

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Copyright Owner

Xia et al

Language

en

File Format

application/pdf

Share

COinS