Evolutionary dynamics of the DNA-binding domains in putative R2R3-MYB genes identified from rice subspecies indica and japonica genomes

No Thumbnail Available
Authors
Jia, Li
Clegg, Michael T.
Jiang, Tao
Advisors
Issue Date
2004-02
Type
Article
Keywords
Research Support, Non-U.S. Gov't , Research Support, U.S. Gov't, Non-P.H.S. , Research Support, U.S. Gov't, P.H.S.
Research Projects
Organizational Units
Journal Issue
Citation
Plant physiology. 2004 Feb; 134(2): 575-85.
Abstract

The molecular evolution of the R2R3-MYB gene family is of great interest because it is one of the most important transcription factor gene families in the plant kingdom. Comparative analyses of a gene family may reveal important adaptive changes at the protein level and thereby provide insights that relate structure to function. We have performed a range of comparative and bioinformatics analyses on R2R3-MYB genes identified from the rice (Oryza sativa subsp. japonica and indica) and Arabidopsis genome sequences. The study provides an initial framework to investigate how different evolutionary lineages in a gene family evolve new functions. Our results reveal a remarkable excess of non-synonymous substitutions, an indication of adaptive selection on protein structure that occurred during the evolution of both helix1 and helix2 of rice R2R3-MYB DNA-binding domains. These flexible alpha-helix regions associated with high frequencies of excess non-synonymous substitutions may play critical roles in the characteristic packing of R2R3-MYB DNA-binding domains and thereby modify the protein-DNA interaction process resulting in the recognition of novel DNA-binding sites. Furthermore, a co-evolutionary pattern is found between the second alpha-helix of the R2 domain and the second alpha-helix of the R3 domain by examining all the possible alpha-helix pairings in both the R2 and R3 domains. This points to the functional importance of pairing interactions between related secondary structures.

Table of Contents
Description
Click on the DOI link below to access the article (may not be free).
Publisher
American Society of Plant Biologists
Journal
Book Title
Series
Plant physiology
PubMed ID
DOI
ISSN
0032-0889
EISSN