Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).

Environmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra) is an economically and ecological...

Full description

Bibliographic Details
Main Authors: Yanguang Chu, Qinjun Huang, Bingyu Zhang, Changjun Ding, Xiaohua Su
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2014-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4041773?pdf=render
_version_ 1811265222007062528
author Yanguang Chu
Qinjun Huang
Bingyu Zhang
Changjun Ding
Xiaohua Su
author_facet Yanguang Chu
Qinjun Huang
Bingyu Zhang
Changjun Ding
Xiaohua Su
author_sort Yanguang Chu
collection DOAJ
description Environmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra) is an economically and ecologically important forest tree species with widely distributed populations and is thus suitable for experiments detecting evolutionary footprints left by stress. Here, we performed expression and evolutionary analysis of two duplicated DREB A1-subgroup (DREB1) genes, PnDREB68 and PnDREB69, encoding transcription factors that are involved in stress responses. The two genes showed partially overlapping but distinct expression patterns in response to stresses. These genes were strongly and rapidly induced by cold stress in leaves, stems, and roots. In leaf tissue, dehydration stress induced the expression of PnDREB68 but not PnDREB69. PnDREB69 displayed more rapid responses and longer expression durations than PnDREB68 under salt and ABA stress, respectively. Based on single nucleotide polymorphism (SNP) analysis, we found significant population genetic differentiation, with a greater FST value (0.09189) for PnDREB69 than for PnDREB68 (0.07743). Nucleotide diversity analysis revealed a two-fold higher πT for PnDREB68 than for PnDREB69 (0.00563 vs. 0.00243), reflecting strong purifying selection acting on the former. The results suggest that positive selection acted on PnDREB69, as evidenced by neutral testing using Tajima's D statistic. The distinct selective forces to which each of the genes was subjected may be associated with expression divergence. Linkage disequilibrium (LD) was low for the sequenced region, with a higher level for PnDREB68 than for PnDREB69. Additionally, analysis of the relationship among carbon isotope ratios, SNP classes and gene expression, together with motif and domain analysis, suggested that 14 polymorphisms within the two genes may be candidates for an association study of important traits such as water use efficiency/drought tolerance in black poplar.
first_indexed 2024-04-12T20:18:41Z
format Article
id doaj.art-ddd312d48a6442ac9e1a8a11116277e2
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-04-12T20:18:41Z
publishDate 2014-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-ddd312d48a6442ac9e1a8a11116277e22022-12-22T03:18:03ZengPublic Library of Science (PLoS)PLoS ONE1932-62032014-01-0196e9833410.1371/journal.pone.0098334Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).Yanguang ChuQinjun HuangBingyu ZhangChangjun DingXiaohua SuEnvironmental stresses such as low temperature, drought, and high salinity significantly affect plant growth and yield. As selective forces, these adverse factors play essential roles in shaping phenotypic variation in plant populations. Black poplar (Populus nigra) is an economically and ecologically important forest tree species with widely distributed populations and is thus suitable for experiments detecting evolutionary footprints left by stress. Here, we performed expression and evolutionary analysis of two duplicated DREB A1-subgroup (DREB1) genes, PnDREB68 and PnDREB69, encoding transcription factors that are involved in stress responses. The two genes showed partially overlapping but distinct expression patterns in response to stresses. These genes were strongly and rapidly induced by cold stress in leaves, stems, and roots. In leaf tissue, dehydration stress induced the expression of PnDREB68 but not PnDREB69. PnDREB69 displayed more rapid responses and longer expression durations than PnDREB68 under salt and ABA stress, respectively. Based on single nucleotide polymorphism (SNP) analysis, we found significant population genetic differentiation, with a greater FST value (0.09189) for PnDREB69 than for PnDREB68 (0.07743). Nucleotide diversity analysis revealed a two-fold higher πT for PnDREB68 than for PnDREB69 (0.00563 vs. 0.00243), reflecting strong purifying selection acting on the former. The results suggest that positive selection acted on PnDREB69, as evidenced by neutral testing using Tajima's D statistic. The distinct selective forces to which each of the genes was subjected may be associated with expression divergence. Linkage disequilibrium (LD) was low for the sequenced region, with a higher level for PnDREB68 than for PnDREB69. Additionally, analysis of the relationship among carbon isotope ratios, SNP classes and gene expression, together with motif and domain analysis, suggested that 14 polymorphisms within the two genes may be candidates for an association study of important traits such as water use efficiency/drought tolerance in black poplar.http://europepmc.org/articles/PMC4041773?pdf=render
spellingShingle Yanguang Chu
Qinjun Huang
Bingyu Zhang
Changjun Ding
Xiaohua Su
Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
PLoS ONE
title Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
title_full Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
title_fullStr Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
title_full_unstemmed Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
title_short Expression and molecular evolution of two DREB1 genes in black poplar (Populus nigra).
title_sort expression and molecular evolution of two dreb1 genes in black poplar populus nigra
url http://europepmc.org/articles/PMC4041773?pdf=render
work_keys_str_mv AT yanguangchu expressionandmolecularevolutionoftwodreb1genesinblackpoplarpopulusnigra
AT qinjunhuang expressionandmolecularevolutionoftwodreb1genesinblackpoplarpopulusnigra
AT bingyuzhang expressionandmolecularevolutionoftwodreb1genesinblackpoplarpopulusnigra
AT changjunding expressionandmolecularevolutionoftwodreb1genesinblackpoplarpopulusnigra
AT xiaohuasu expressionandmolecularevolutionoftwodreb1genesinblackpoplarpopulusnigra