Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

The Maize Oil Yellow1 (Oy1) Gene Encodes the I Subunit of Magnesium Chelatase

The Maize Oil Yellow1 (Oy1) Gene Encodes the I Subunit of Magnesium Chelatase Semi-dominant Oil yellow1 (Oy1) mutants of maize (Zea mays) are deficient in the conversion of protoporphyrin IX to magnesium protoporphyrin IX, the first committed step of chlorophyll biosynthesis. Using a candidate gene approach, a cDNA clone was isolated that was predicted to encode the I subunit of magnesium chelatase (ZmCHLI) and mapped to the same genetic interval as Oy1. Allelic variation was identified at ZmCHLI between wild-type plants and plants carrying semi-dominant alleles of Oy1. These differences revealed putative amino acid substitutions that could account for the alterations in protein function. Candidate lesions were tested by introduction of homologous changes into the Synechocystis magnesium chelatase I gene (SschlI) and characterization of the activity of mutant protein variants in an in vitro enzyme activity assay. The results of these analyses suggest that SsChlI protein variants containing the substitutions identified in the dominant Oy1 maize alleles lack activity necessary for magnesium chelation and confer a semi-dominant phenotype via competitive inhibition of wild-type SsChlI. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Molecular Biology Springer Journals

The Maize Oil Yellow1 (Oy1) Gene Encodes the I Subunit of Magnesium Chelatase

Loading next page...
 
/lp/springer_journal/the-maize-oil-yellow1-oy1-gene-encodes-the-i-subunit-of-magnesium-QuRRtlFf4Z

References (52)

Publisher
Springer Journals
Copyright
Copyright © 2006 by Springer
Subject
Life Sciences; Biochemistry, general; Plant Sciences; Plant Pathology
ISSN
0167-4412
eISSN
1573-5028
DOI
10.1007/s11103-005-2880-0
pmid
16463102
Publisher site
See Article on Publisher Site

Abstract

Semi-dominant Oil yellow1 (Oy1) mutants of maize (Zea mays) are deficient in the conversion of protoporphyrin IX to magnesium protoporphyrin IX, the first committed step of chlorophyll biosynthesis. Using a candidate gene approach, a cDNA clone was isolated that was predicted to encode the I subunit of magnesium chelatase (ZmCHLI) and mapped to the same genetic interval as Oy1. Allelic variation was identified at ZmCHLI between wild-type plants and plants carrying semi-dominant alleles of Oy1. These differences revealed putative amino acid substitutions that could account for the alterations in protein function. Candidate lesions were tested by introduction of homologous changes into the Synechocystis magnesium chelatase I gene (SschlI) and characterization of the activity of mutant protein variants in an in vitro enzyme activity assay. The results of these analyses suggest that SsChlI protein variants containing the substitutions identified in the dominant Oy1 maize alleles lack activity necessary for magnesium chelation and confer a semi-dominant phenotype via competitive inhibition of wild-type SsChlI.

Journal

Plant Molecular BiologySpringer Journals

Published: Sep 7, 2005

There are no references for this article.