中文摘要：

根据棉花纤维特异表达cDNA文库分析得到的4-香豆酸辅酶A连接酶基因EST序列设计引物,采用RT-PCR技术从棉花中克隆了1个4CL基因,命名为Gh4CL1（GenBank登录号为FJ479707）.结果表明：Gh4CL1基因cDNA全长2 331 bp,具有1个1 722 bp的开放阅读框,5′非编码区为64 bp,3′非编码区为445 bp,编码573个氨基酸,预测分子量约为61.951 kD,等电点为5.70.氨基酸同源性分析发现,Gh4CL1与来自白杨、大豆和紫草的4CL同源性较高.半定量RT-PCR检测表明,Gh4CL1基因在不同发育阶段的棉纤维中均有表达,在开花后20 d的棉纤维中表达量最大,说明该基因可能参与调控棉纤维细胞的伸长和次生壁的增厚.Gh4CL1基因在棉花花瓣中表达量最高,在其他组织中低水平表达或不表达.

英文摘要：

According to results of cotton fibre preferentially expressed cDNA library analysis,primers of EST sequence were designed.RT-PCR method was used to clone 4CL gene,a gene coding for 4CL,designated as Gh4CL1（GenBank accession No.FJ479707） was isolated from cotton（Gossypium hirsutum L.）.The full length Gh4CL1 cDNA is 2 331 bp,including a 64 bp 5′-UTR,an ORF of 1 722 bp,and a 445 bp 3′-UTR.This cDNA sequence encoded a polypepide of 573 amino acid residues with a predicted molecular mass of 61.951 kDa and a basic isoelectric point of 5.70.The deduced amino acid sequence had a high homology with 4CL from Populus tremuloides,Glycine max,and Lithospermum erythrorhizon.Semi-quantitative RT-PCR analysis revealed that Gh4CL1 was expressed during different fibre developmental stages,and reached to the peak of expression in 20 days post anthers（DPA） fibre cells,suggesting that this gene may be involved in regulating fibre elongationg and secondary wall thickening.The gene is also expressed at higher level in petal,but displays lower or undetectable level in other tissues of cotton.