摘要： 为了探究不同光质以及转光条件对葡萄CO4基因表达水平及试管苗叶绿素荧光参数的影响，利用RT-PCR技术，从葡萄贝达试管苗中克隆了一个光质响应基因CO4（GenBank登录号为KY652090），并对其进行生物信息学以及qRT-PCR分析。结果表明，CO4基因片段全长663 bp，编码了248个氨基酸，其开放阅读框为747 bp；葡萄CO4有4个跨膜区，预测其为跨膜蛋白；葡萄CO4的分子式为C₁₂₅₃H₁₉₉₀N₃₂₄O₃₄₀S₁₁，预测是疏水性不稳定蛋白。系统进化树分析表明，该蛋白与巨桉CO4最为相似。经荧光实时定量PCR分析表明，在红光转蓝光处理下葡萄CO4表达量显著高于白光（对照），是对照的5.39倍；其次为蓝光处理；在白光转蓝光条件下CO4表达量最低，是对照的54%；红白转光处理下CO4表达量与对照无显著差异。叶绿素荧光参数分析结果显示，红光转蓝光处理后的Fv/Fm （最大光化学效率）、Fv/Fo （潜在活性）和qP （光化学猝灭系数）均显著高于对照，NPQ在该处理下（非光化学猝灭系数）最低；在红光处理下NPQ最高，Fv/Fm、qP最低。葡萄CO4对光质敏感，且在不同光质及转光条件下其响应水平不同，红光转蓝光处理下上调表达显著，且该光照条件下能显著促进葡萄试管苗的光化学能力。为深入研究CO基因在葡萄试管苗感光机理中的作用提供理论依据，并为葡萄光质改良奠定基础。

关键词: 葡萄, CO4, 基因表达, 光质, 叶绿素荧光参数

Abstract: To explore the effects of different light qualities on the expression of CO4 gene in grapevine plantlet in vitro. The full-length cDNA sequence of CO4 was cloned from Vitis riparia×V.labrusca Beta in vitro by RT-PCR. Bioinformatics analysis of the second level structure, and phylogenetic tree of protein. The result showed that the size of CO4 gene fragment was 663 bp, the open reading frame (ORF)of CO4 gene was 747 bp, including 248 amino acid coding regions. By use bioinformation analysis, CO4 of Beta was a hydrophobic, unstable protein with good lipid solubility. CO4 had a signal peptide, it can be inferred that it was a transmembrane protein. Phylogenetic tree indicated that CO4 of Beta (Vitis riparia×V.labrusca)had the highest evolutionary relationship with Eucalyptus grandis (Eucalyptus grandis Hill ex Maiden).qRT-PCR analysis showed that the CO4 expressed specifically and strongly in the treatment of red to blue light (control), which increased 5.39 fold in comparison to the control. The difference was not significant when exposed to the treatment of white to red light and red to white light. However the expression of CO4 was the lowest in the white to blue light treatment, which was 54% of the control. Fluorescence parameter analysis showed that the maximum photochemical efficiency (Fv/Fm), potential activity (Fv/Fo)and photochemical quenching coefficient (qP)were significantly higher than those of the control under red to blue light. The non photochemical quenching coefficient (NPQ)was the lowest under that treatment, but was the highest under red light treatment, it was the lowest under this treatment. The CO4 of Beta was more sensitive to light. The treatments of red to blue light could not only promote the expression of CO4, but also could improve the Beta Grapevine in vitro photosynthetic capacity. Thus, red to blue light played an important role in the process of morphogenesis of Beta Grapevine in vitro.

Key words: Grapevine, CO4, Gene expression, Light quality, Chlorophyll fluorescence parameters

中图分类号: 

• Q78

• S663.03