海岛棉GbHCT基因克隆及生物信息学分析

摘要

This study is to isolate full-length cDNA of a key enzyme gene GbHCT related to lignin metabolism in cotton(Gossypium barbadense L.),and analyze the expression of GbHCT in the different developing stages of cotton’s fiber. The primers were designed according to the HCT sequence in transcriptome data of sea island cotton,then the gene was cloned using RT-PCR,and the cDNA sequence and the amino acid sequence of GbHCT were analyzed by bioinformatics methods. The expressions of gene GbHCT in developing fibers of cotton were analyzed from the transcriptome data of sea island cotton. A gene encoding HCT,designated as GbHCT,was isolated from G. barbadense. The full-length of the GbHCT consisted of a 1,311 bp open reading frame(ORF)encoding 436 amino acids. The molecular weight of protein was 48.58 kD,with an isoelectric point(pI)of 6.03. The deduced amino acid sequence of the GbHCT had two conservative motifs HTLGD and DFGWG. The deduced amino acid sequence had a high homology with HCT from Gossypium hirsutum,Gossypium arboretum and Gossypium raimondii,however,it showed 55.7%-60.7% identities with HCTs of other plants. Analyzing the transcriptome data of sea island cotton revealed that gene GbHCT was expressed in all different development stages of fiber,and the peak of expression reached in 5 days post anthers (DPA)fiber cells,suggesting that this gene may be involved in fiber development.%克隆海岛棉木质素合成关键酶基因GbHCT全长cDNA序列，分析其在纤维不同发育时期的表达情况。根据海岛棉转录组数据中的HCT序列设计引物，采用RT-PCR技术克隆基因，通过生物信息学方法分析GbHCT的cDNA序列和氨基酸序列。通过分析转录组数据研究GbHCT在纤维不同发育时期的表达。从海岛棉中克隆了1个编码HCT的基因GbHCT，开放阅读框长度为1311 bp，编码436个氨基酸，蛋白质分子量为48.58 kD，等电点为6.03。GbHCT氨基酸序列中含有HTLGD和DFGWG 2个保守基序。GbHCT氨基酸与陆地棉、亚洲棉和雷蒙德氏棉HCT一致性较高，与其他植物中的HCT氨基酸的一致性为55.7%-60.7%。转录组数据分析发现GbHCT在纤维不同发育阶段都有表达，在5 DPA的纤维中表达量最高，表明该基因可能参与棉花纤维的发育。