Duplication and adaptive evolution of the COR15 genes within the highly cold-tolerant Draba lineage (Brassicaceae)

NWIPB OpenIR

	Duplication and adaptive evolution of the COR15 genes within the highly cold-tolerant Draba lineage (Brassicaceae)
	Zhou, Dangwei 1,2; Zhou, Jie 3; Meng, Lihua 2; Wang, Qingbiao 3; Xie, He 1; Guan, Yucheng 1; Ma, Zeyang 1; Zhong, Yang 3; Chen, Fan 1; Liu, Jianquan 2
	2009-07-15
发表期刊	GENE
ISSN	0378-1119
卷号	441 期号:1-2 页码:36-44
文章类型	Article
摘要	Plants have evolved diverse adaptive mechanisms that enable them to tolerate abiotic stresses, to varying degrees, and such stresses may have strongly influenced evolutionary changes at levels ranging from molecular to morphological. Previous studies on these phenomena have focused on the adaptive evolution of stress-related orthologous genes in specific lineages. However, heterogenetic evolution of the paralogous genes following duplication has only been examined in a very limited number of stress-response gene families. The COR15 gene encodes a low molecular weight protein that plays an important role in protecting plants from cold stresses. Although two different copies of this gene have been found in the model species, Arabidopsis thaliana, evolutionary patterns of this small gene family in plants have not been previously explored. In this study, we cloned COR15-like sequences and performed evolutionary analyses of these sequences (including those previously reported) in the highly cold-tolerant Draba lineage and related lineages of Brassicaceae. Our phylogenetic analyses indicate that all COR15-like sequences clustered into four clades that corresponded well to the morphological lineages. Gene conversions were found to have probably occurred before/during the divergence of Brassica and Draba lineage. However, repeated, independent duplications of this gene have occurred in different lineages of Brassicaceae. Further comparisons of all sequences suggest that there have been significant inter-lineage differences in evolutionary rates between the duplicated and original genes. We assessed the likelihood that the differences between two well-supported gene subfamilies that appear to have originated from a single duplication, COR15a and COR15b, within the Draba lineage have been driven by adaptive evolution. Comparisons of their non-synonymous/synonymous substitution ratios and rates of predicted amino acid changes indicate that these two gene groups are evolving under different selective pressures and may be functionally divergent. This functional divergence was confirmed by comparing site-specific shifts in evolution indexes of the two groups of predicted proteins. The evidence of differential selection and possible functional divergence suggests that the duplication may be of adaptive significance, with possible implications for the explosive diversification of the Draba lineage during the cooling Quaternary stages and the following worldwide colonization of and alpine and artic regions. (C) 2008 Elsevier B.V. All rights reserved.; Plants have evolved diverse adaptive mechanisms that enable them to tolerate abiotic stresses, to varying degrees, and such stresses may have strongly influenced evolutionary changes at levels ranging from molecular to morphological. Previous studies on these phenomena have focused on the adaptive evolution of stress-related orthologous genes in specific lineages. However, heterogenetic evolution of the paralogous genes following duplication has only been examined in a very limited number of stress-response gene families. The COR15 gene encodes a low molecular weight protein that plays an important role in protecting plants from cold stresses. Although two different copies of this gene have been found in the model species, Arabidopsis thaliana, evolutionary patterns of this small gene family in plants have not been previously explored. In this study, we cloned COR15-like sequences and performed evolutionary analyses of these sequences (including those previously reported) in the highly cold-tolerant Draba lineage and related lineages of Brassicaceae. Our phylogenetic analyses indicate that all COR15-like sequences clustered into four clades that corresponded well to the morphological lineages. Gene conversions were found to have probably occurred before/during the divergence of Brassica and Draba lineage. However, repeated, independent duplications of this gene have occurred in different lineages of Brassicaceae. Further comparisons of all sequences suggest that there have been significant inter-lineage differences in evolutionary rates between the duplicated and original genes. We assessed the likelihood that the differences between two well-supported gene subfamilies that appear to have originated from a single duplication, COR15a and COR15b, within the Draba lineage have been driven by adaptive evolution. Comparisons of their non-synonymous/synonymous substitution ratios and rates of predicted amino acid changes indicate that these two gene groups are evolving under different selective pressures and may be functionally divergent. This functional divergence was confirmed by comparing site-specific shifts in evolution indexes of the two groups of predicted proteins. The evidence of differential selection and possible functional divergence suggests that the duplication may be of adaptive significance, with possible implications for the explosive diversification of the Draba lineage during the cooling Quaternary stages and the following worldwide colonization of and alpine and artic regions. (C) 2008 Elsevier B.V. All rights reserved.
关键词	Gene Duplication Adaptive Evolution Cor15 Functional Divergence Draba
WOS标题词	Science & Technology ; Life Sciences & Biomedicine
关键词[WOS]	ARABIDOPSIS-THALIANA ; FREEZING TOLERANCE ; NUCLEOTIDE SUBSTITUTIONS ; MOLECULAR EVOLUTION ; POSITIVE SELECTION ; ENVIRONMENTAL-STRESS ; NATURAL-SELECTION ; DNA-SEQUENCES ; FAMILY ; DIVERSITY
收录类别	SCI
语种	英语
WOS研究方向	Genetics & Heredity
WOS类目	Genetics & Heredity
WOS记录号	WOS:000267229600006
引用统计	被引频次：21[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/1846
专题	中国科学院西北高原生物研究所
作者单位	1.Chinese Acad Sci, Inst Genet & Dev Biol, Key Lab Mol & Dev Biol, Beijing 100080, Peoples R China 2.Chinese Acad Sci, Key Lab Adaptat & Evolut Plateau Biota, NW Plateau Inst Biol, Beijing 810001, Qinghai, Peoples R China 3.Fudan Univ, MOE Key Lab Biodivers Sci & Ecol Engn, Sch Life Sci, Shanghai 200433, Peoples R China
推荐引用方式 GB/T 7714	Zhou, Dangwei,Zhou, Jie,Meng, Lihua,et al. Duplication and adaptive evolution of the COR15 genes within the highly cold-tolerant Draba lineage (Brassicaceae)[J]. GENE,2009,441(1-2):36-44.
APA	Zhou, Dangwei.,Zhou, Jie.,Meng, Lihua.,Wang, Qingbiao.,Xie, He.,...&Liu, Jianquan.(2009).Duplication and adaptive evolution of the COR15 genes within the highly cold-tolerant Draba lineage (Brassicaceae).GENE,441(1-2),36-44.
MLA	Zhou, Dangwei,et al."Duplication and adaptive evolution of the COR15 genes within the highly cold-tolerant Draba lineage (Brassicaceae)".GENE 441.1-2(2009):36-44.