Molecular analysis of the chloroplast Cu/Zn-SOD gene (AhCSD2) in peanut
Molecular analysis of the chloroplast Cu/Zn-SOD gene (AhCSD2) in peanut
复制标题
花生叶绿体 Cu/Zn-SOD 基因 (AhCSD2) 的分子分析
DOI：
10.1016/j.cj.2015.03.006
复制
发表时间：
2015
期刊：
影响因子：
6.6
通讯作者：
Y. Wan
中科院分区：
文献类型：
--
作者：
Xiurong Zhang;Qian Wan;Fengzhen Liu;Kun;Ai;B. Luo;Li Sun;Y. Wan
超氧化物歧化酶（SOD，EC 1.15.1.1）在干旱胁迫下起着关键作用，干旱条件下SOD活性变化的品种间差异是重要的。从11个异源四倍体花生品种和5个二倍体野生种中获得了叶绿体Cu/Zn-SOD基因（AhCSD 2）的全长DNA。对花生基因组的BLAST分析表明，AhCSD 2基因gCSD 2 - 1和gCSD 2 - 2分别位于A03（A基因组）和B 03（B基因组）染色体的顶端，均含有8个外显子和7个内含子。核苷酸序列分析表明，供试品种gCSD 2 - 2序列完全相同，而gCSD 2 - 1序列存在等位变异。gCSD 2 - 1和gCSD 2 - 2推导的氨基酸序列均含有一个叶绿体转运肽，并通过6个氨基酸（aa）残基差异来区分。成熟肽区另外2个氨基酸残基的变异导致gCSD 2 - 1和gCSD 2 - 2基因推导的蛋白质三维结构发生变化。根据A. hypogaea和A基因组野生种的氨基酸序列，推导了AhCSD 2 -1（A. hypogaea）的氨基酸序列。hypogaea）与AduCSD 2（Arachis duranensis）相同，而AcoCSD 2（Arachis correntina）和AcoCSD 2（Arachis cardenasii）与AhCSD 2 -1（Arachis cardenasii）相比，在转运肽区都有2个氨基酸的差异。hypogaea）。基于花生基因组计划的启动子预测结果显示，在可能的启动子区域（pp-A和B）内存在许多与胁迫相关的顺式作用元件，pp-A比pp-B含有更多的干旱相关转录因子的结合位点。我们推测干旱胁迫下不同品种SOD活性的显著变化是受转录因子通过AhCSD 2基因的转录和表达而紧密调控的。
Superoxide dismutase (SOD, EC 1.15.1.1) plays a key role in response to drought stress, and differences in SOD activity changes among cultivars are important under drought conditions. We obtained the full-length DNA of the chloroplast Cu/Zn-SOD gene (AhCSD2) from 11 allotetraploid cultivars and 5 diploid wild species in peanut. BLAST search against the peanut genome showed that theAhCSD2genesgCSD2-1andgCSD2-2are located at the tops of chromosome A03 (A genome) and B03 (B genome), respectively, and both contain 8 exons and 7 introns. Nucleotide sequence analyses indicated thatgCSD2-2sequences were identical among all the tested cultivars, whilegCSD2-1sequences showed allelic variations. The amino acid sequences deduced fromgCSD2-1andgCSD2-2both contain a chloroplast transit peptide and are distinguished by 6 amino acid (aa) residue differences. The other 2 aa residue variations in the mature peptide regions give rise to three-dimensional structure changes of the protein deduced from the genesgCSD2-1andgCSD2-2.Sequences analyses of cultivars and wild species showed thatgCSD2-2ofArachis hypogaeaandgAipCSD2(Arachis ipaensis) are identical, and despite the abundant polymorphic loci betweengCSD2-1ofA. hypogaeaand sequences from A genome wild species, the deduced amino acid sequence of AhCSD2-1 (A. hypogaea) is identical to that of AduCSD2 (Arachis duranensis), whereas AcoCSD2 (Arachis correntina) and AcaCSD2 (Arachis cardenasii) both have 2 aa differences in the transit peptide region compared with AhCSD2-1 (A. hypogaea). Based on the Peanut Genome Project, promoter prediction revealed many stress-relatedcis-acting elements within the potential promoter regions (pp-Aandpp-B).pp-Acontains more binding sites for drought-associated transcriptional factors thanpp-B. We hypothesize that the marked changes in SOD activity in different cultivars under drought stress are tightly regulated by transcription factors through transcription and expression ofAhCSD2genes.