Affordable Access

Publisher Website

Maize nitrilases have a dual role in auxin homeostasis and beta-cyanoalanine hydrolysis.

Authors
Type
Published Article
Journal
Journal of Experimental Botany
1460-2431
Publisher
Oxford University Press
Publication Date
Volume
58
Issue
15-16
Pages
4225–4233
Identifiers
DOI: 10.1093/jxb/erm279
PMID: 18182427
Source
Medline

Abstract

The auxin indole-3-acetic acid (IAA), which is essential for plant growth and development, is suggested to be synthesized via several redundant pathways. In maize (Zea mays), the nitrilase ZmNIT2 is expressed in auxin-synthesizing tissues and efficiently hydrolyses indole-3-acetonitrile to IAA. Zmnit2 transposon insertion mutants were compromised in root growth in young seedlings and sensitivity to indole-3-acetonitrile, and accumulated lower quantities of IAA conjugates in kernels and root tips, suggesting a substantial contribution of ZmNIT2 to total IAA biosynthesis in maize. An additional enzymatic function, turnover of beta-cyanoalanine, is acquired when ZmNIT2 forms heteromers with the homologue ZmNIT1. In plants carrying an insertion mutation in either nitrilase gene this activity was strongly reduced. A dual role for ZmNIT2 in auxin biosynthesis and in cyanide detoxification as a heteromer with ZmNIT1 is therefore proposed.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments