Publication Date

11-12-2020

Department

Ames Laboratory; Biochemistry, Biophysics and Molecular Biology, Roy J. Carver Department of; Genetics, Development and Cell Biology; Plant Pathology and Microbiology

Campus Units

Ames Laboratory, Biochemistry, Biophysics and Molecular Biology, Roy J. Carver Department of, Genetics, Development and Cell Biology, Plant Pathology and Microbiology

OSTI ID+

1783232

Report Number

IS-J 10480

DOI

10.3390/plants9111558

Journal Title

Plants

Volume Number

9

Issue Number

11

First Page

1558

Abstract

Pectin is a critical component of the plant cell wall, supporting wall biomechanics and contributing to cell wall signaling in response to stress. The plant cell carefully regulates pectin methylesterification with endogenous pectin methylesterases (PMEs) and their inhibitors (PMEIs) to promote growth and protect against pathogens. We expressed Aspergillus nidulans pectin methylesterase (AnPME) in Arabidopsis thaliana plants to determine the impacts of methylesterification status on pectin function. Plants expressing AnPME had a roughly 50% reduction in methylester content compared with control plants. AnPME plants displayed a severe dwarf phenotype, including small, bushy rosettes and shorter roots. This phenotype was caused by a reduction in cell elongation. Cell wall composition was altered in AnPME plants, with significantly more arabinose and significantly less galacturonic acid, suggesting that plants actively monitor and compensate for altered pectin content. Cell walls of AnPME plants were more readily degraded by polygalacturonase (PG) alone but were less susceptible to treatment with a mixture of PG and PME. AnPME plants were insensitive to osmotic stress, and their susceptibility to Botrytis cinerea was comparable to wild type plants despite their compromised cell walls. This is likely due to upregulated expression of defense response genes observed in AnPME plants. These results demonstrate the importance of pectin in both normal growth and development, and in response to biotic and abiotic stresses.

DOE Contract Number(s)

AC02-07CH11358; 015227-00005; MCB-1616316

Language

en

Department of Energy Subject Categories

59 BASIC BIOLOGICAL SCIENCES

Publisher

Iowa State University Digital Repository, Ames IA (United States)

Included in

Plant Biology Commons

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