棉花冠菌素不敏感因子GhCOI1基因分离和对大丽轮枝菌的抗性分析

Isolation of Cotton Coronatine Insensitive Factor Gene(GhCOI1)and Its Function in Cotton Resistance Against Verticillium dahliae Infection

为了解决黄萎病对棉花的危害,利用基因工程技术培育抗病棉花品种是当前育种的主要目标。从棉花中克隆了一个黄萎病抗性基因GhCOI1,其编码冠菌素不敏感因子。GhCOI1基因序列全长2 213 bp,编码一个600氨基酸的多肽,分子量为68 k Da,等电点p I是7.06。GhCOI1含有典型的F-box和LRR结构域。组织表达分析表明,该基因在根器官优势表达,并且其表达受到大丽轮枝菌浸染诱导。利用病毒诱导基因沉默(Virus-induced gene silencing,VIGS)技术,抑制了GhCOI1基因在棉花植株中的表达;通过大丽轮枝菌接菌分析表明,GhCOI1基因沉默能够引起植株的抗性下降,发病加重。研究结果表明GhCOI1参与棉花对大丽轮枝菌抗性调控,因此,其可以作为棉花抗病育种的候选基因。

Since Verticillium wilt takes a large loss in cotton production every year,cotton resistant cultivars developed by genetic engineering methods have been urgently demanded in cotton production. We isolated a cotton CORONATINE INSENSITIVE1（ COI1） gene,named GhCOI1. The full-length c DNA of GhCOI1 gene was 2 213 bp,encoding a 600 amino acid peptide with a predicted molecular mass of 68 k Da and an isoelectric point（ p I） of7. 06. GhCOI1 contains both typical F-box and LRR conserved domains. By RT-PCR and qPCR analyses,GhCOI1 gene was dominantly expressed in roots. And it was continuously induced overtime by Verticillium dahliae. The cotton plants with knock down of GhCOI1 gene were successfully developed by virus-induced gene silencing（ VIGS）techniques. When VIGS-plants were challenged with V. dahliae,resistance of these plants significantly reduced according to analyses of rates of diseased plants and disease index compared to the control. All together,the results indicated that GhCOI1 was involved in cotton resistance to Verticillium wilt,which can be used as a candidate gene in the cotton resistant breeding.