环核苷酸门控通道(CNGC)作为Ca2+渗透阳离子转运途径,参与调节各种生物学功能,如植物细胞离子选择性通透性,成长和发展,对生物和非生物胁迫的反应。在目前的研究中,在洋麻中共鉴定了31个CNGC基因,并进行了生物信息学分析.在这些基因中,HcCNGC21的特征是位于质膜,在叶子中表达水平最高,其次是根。此外,HcCNGC21在盐或干旱胁迫下可显著诱导。在盐或干旱胁迫下,红麻中HcCNGC21的病毒诱导基因沉默(VIGS)引起明显的生长抑制,以植物高度降低为特征,阀杆直径,叶面积,根长,根表面积,和根尖号。同时,超氧化物歧化酶(SOD)的活性,过氧化物酶(POD)和过氧化氢酶(CAT)显著降低,伴随着渗透调节物质和总叶绿素含量的降低。然而,ROS积累和Na+含量增加。应激反应基因的表达,如HcSOD,HcPOD,HcCAT,HcERF3,HcNAC29,HcP5CS,HcLTP,和HcNCED,在这些沉默的系中显著下调。然而,在盐或干旱胁迫下,过表达HcCNGC21的转基因拟南芥植物的生理特性和胁迫相关基因的表达与pTRV2-HcCNGC21洋麻品系完全相反。酵母双杂交(Y2H)和双分子荧光互补(BiFC)分析显示,HcCNGC21与HcAnnexinD1相互作用。这些发现共同强调了HcCNGC21在植物对盐和干旱胁迫的抗性中的积极作用。
Cyclic Nucleotide-Gated Channels (CNGCs) serve as Ca2+ permeable cation transport pathways, which are involved in the regulation of various biological functions such as plant cell ion selective permeability, growth and development, responses to biotic and abiotic stresses. At the present study, a total of 31 CNGC genes were identified and bioinformatically analyzed in kenaf. Among these genes, HcCNGC21 characterized to localize at the plasma membrane, with the highest expression levels in leaves, followed by roots. In addition, HcCNGC21 could be significantly induced under salt or drought stress. Virus-induced gene silencing (VIGS) of HcCNGC21 in kenaf caused notable growth inhibition under salt or drought stress, characterized by reductions in plant height, stem diameter, leaf area, root length, root surface area, and root tip number. Meanwhile, the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were significantly decreased, accompanied by reduced levels of osmoregulatory substances and total chlorophyll content. However, ROS accumulation and Na+ content increased. The expression of stress-responsive genes, such as HcSOD, HcPOD, HcCAT, HcERF3, HcNAC29, HcP5CS, HcLTP, and HcNCED, was significantly downregulated in these silenced lines. However, under salt or drought stress, the physiological performance and expression of stress-related genes in transgenic Arabidopsis thaliana plants overexpressing HcCNGC21 were diametrically opposite to those of TRV2-HcCNGC21 kenaf line. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays revealed that HcCNGC21 interacts with HcAnnexin D1. These findings collectively underscore the positive role of HcCNGC21 in plant resistance to salt and drought stress.