棉纤维伸长阶段上、下调基因及相关通路的分析

Up-and Down-Regulated Genes during Cotton Fiber Elongation and Relative Pathway

棉花纤维细胞是研究细胞发育机制的理想材料,陆地棉Ligon lintless(Li1)是单基因显性超短纤维突变体,其性状表现为长纤维极度缩短,分离得到的野生型(li1)纤维发育正常。本实验通过cDNA芯片的方法对2个材料进行比较分析,采集开花前1d到开花后7d材料,检测到多个上调和下调基因,选择2个基因(CIPK和XET)进行RT-PCR和qRT-PCR的芯片验证。应用MAS(molecular analysis system)系统进行GO功能注释和Pathway的分析表明,这些差异表达基因参与脂肪酸代谢(fatty acid metabolism)、甘油脂代谢(glycerolipid metabolism)以及碳固定(reductive carboxylate cycle)等多个代谢途径。这些基因在突变体Li1中的异常表达可能导致细胞中脂肪酸和脂肪含量变化,影响棉纤维细胞的正常发育。

The fiber development is a crucial factor,influencing cotton yield and quality.The elongation period of fiber development is the key time to determine the fiber＇s final length.The mechanism of fiber elongation is not known clearly now.We hope to find some information about it by using wild type and mutant microarray.It is an effective method to studying relevant genes of fiber development by comparing mutants and wild-type gene expression profiles.Cotton fiber formed by single-celled trichomes is the perfect material for studying cell elongation mechanism.Ligon lintless（Li1） is a dominant mutant of upland cotton（Gossypium hirsutum L.） and its fiber is extremely short on mature seed,about 4-6 mm in length,but the wild type（li） is normal for plant and fibers.Recently,we constructed a cDNA microarray used the ovule total RNAs of the mutant and its wild-type.The results showed that many genes expressed up-or down-regulated between the mutant and wild type from-1 to ＋7 DPA（day post anthesis）,and two genes（XET and CIPK） were validated by RT-PCR and qRT-PCR analysis.These genes were analyzed via the gene ontology and pathway with Molecule Annotation System（MAS） developed by Capitalbio Co,indicating that these differential expressed genes influenced some metabolism pathways including fatty acid metabolism,glycerolipid metabolism,reductive carboxylate cycle.The abnormal expression of these genes in the mutant Li1 maybe result in the change of the fatty acids and fat content,and further influence the fiber development.