毛竹NLP转录因子鉴定及其响应氮素的表达模式

Identification of NLP Transcription Factors of Phyllostachys edulis and Their Expression Patterns in Response to Nitrogen

[目的]鉴定毛竹中NLP家族成员,为深入研究毛竹NLP分子调控机制奠定基础。[方法]采用生物信息学方法鉴定并系统分析毛竹NLP成员的分子特征,用实时荧光定量PCR(qPCR)技术检测毛竹NLP响应氮素的表达模式。[结果]毛竹中鉴定出10个NLP成员(PeNLP1~PeNLP10),其蛋白长度为714~963 aa,分子量为77.41~105.08 kDa,理论等电点介于5.36~6.25之间;亚细胞定位预测结果表明,除PeNLP9定位于叶绿体外,其余成员均定位于细胞核内。系统进化分析表明:PeNLPs分成3个组,各组成员分别为4、2、4个。PeNLPs均包含4个内含子,不同成员内含子的大小和位置存在一定的差异;PeNLPs内有共线性基因对6个,PeNLPs和OsNLPs之间有共线性基因对9个,且它们的Ka/Ks均小于1,说明其在进化上经历了纯化选择。组织特异性分析表明,有的PeNLPs呈组织特异性表达,有的则呈组成型表达。PeNLPs受到氮饥饿诱导表达,在1 h内PeNLP1的表达量显著上调,其它5个PeNLPs则显著下调(p<0.01);对氮饥饿72 h后的毛竹进行复氮处理,在24 h内所有PeNLPs的表达量均显著或极显著上调(p<0.05或p<0.01)。[结论]毛竹中NLP家族有10个成员,各成员的分子特征和组织表达特异性存在一定的差异,PeNLPs的表达能够对氮饥饿作出快速响应,且在氮饥饿后复氮过程中显著上调表达,响应氮素的诱导。

[Objective]To identify the NLP family members in moso bamboo(Phyllostachys edulis)and lay a foundation for further study on the molecular regulation mechanism of these NLPs.[Method]The molecular characteristics of the NLP members in moso bamboo were identified and analyzed comprehensively by bioinformatics methods,and the expression patterns of the NLPs in response to nitrogen were detected by quantitative real-time PCR(qPCR).[Result]Ten NLP members(PeNLP1~PeNLP10)were identified from moso bamboo.The length of PeNLPs ranged from 714 aa to 963 aa,with the molecular weight of 77.41~105.08 kDa,and the theoretical isoelectric point ranged from 5.36 to 6.25.The prediction of subcellular localization showed that all PeNLPs were located in the nucleus except PeNLP9 in the chloroplast.Phylogenetic analysis showed that PeNLPs could be divided into 3 groups with 4,2 and 4 members,respectively.All PeNLPs contained 4 introns,and there were some differences in the size and position of introns among different members.There were 6 collinear gene pairs in PeNLPs and 9 collinear gene pairs between PeNLPs and OsNLPs,and their Ka/Ks were all less than 1.0,indicating that they had undergone purification selection in evolution.Tissue specific analysis showed that some PeNLPs expressed in tissue-specific manner,while some PeNLPs expressed constitutively.The expression of PeNLPs was induced by nitrogen starvation,and that of PeNLP1 was significantly up-regulated within 1 hour,while those of other 5 PeNLPs were significantly down-regulated(p<0.01).After 72 hours of nitrogen starvation,the seedlings were resupplied with nitrogen,and the expression levels of all PeNLPs were significantly up-regulated(p<0.05 or p<0.01)within 24 hours.[Conclusion]There are 10 members of NLP family identified in moso bamboo.There are some differences in molecular characteristics and tissue expression specificity of each member.The expression of PeNLPs can respond to nitrogen starvation rapidly,and it is significantly up-regulated in the process of nitrogen resupply after nitrogen starvation.