摘要
细胞色素b6f复合体是植物光合电子传递中潜在的限速因子,增强该复合物的活性,将有助于提高植物光合作用的效率,因此开展光合电子传递关键基因的研究具有重要的科学意义。该研究以锦叶栾叶色变异现象为切入点,以栾树及其突变体锦叶栾为材料,利用Li-COR6800光合分析仪测量栾树和锦叶栾生长期内的光合生理指标;结合转录组数据克隆光合关键基因PetC并对其进行生物信息学分析;采用实时定量PCR分析KpPetC基因在不同组织、不同发育时期叶片中的表达模式及与净光合速率之间的相关性;通过P2A串联KpPetC和eGFP构建KpPetC超表达载体,并在84K杨中进行异源遗传转化。结果显示,锦叶栾净光合速率和蒸腾速率普遍低于栾树,胞间CO_(2)浓度显著高于栾树,非气孔限制是其光合速率减弱的主导因素;7月强光高温的天气可能导致锦叶栾光合系统元件受损,产生更严重的光抑制,从而使锦叶栾对强光的耐受性减弱;KpPetC在根、茎、叶、花芽和种子中呈组成型表达,但在叶片中高丰度表达,且与其他组织间存在显著差异;7、8、9月栾树叶片中KpPetC基因的表达量均显著高于锦叶栾,净光合速率与KpPetC基因表达量之间存在正相关关系,推测锦叶栾KpPetC基因表达的下调可能是光合速率下降的主要原因之一。总之,与栾树相比,锦叶栾光合作用能力明显减弱,这可能是KpPetC基因的表达受到抑制,使得光合通路元件受损,最终影响光合电子传递速率。该研究为今后深入研究PetC基因的功能奠定了基础,对于光合电子传递机制的研究具有重要的科学意义。
The cytochrome b6f complex is a potential limiting factor in plant photosynthetic electron transfer,and increasing the activity of this complex may improve the efficiency of photosynthesis.It is of great scientific significance to investigate key genes involved in photosynthetic electron transfer.In this study,starting from color variation phenotype in Koelreuteria paniculata‘Jinye’,and using K.paniculata and its mutant K.paniculata‘Jinye’as experimental materials.The photosynthetic physiological indicators was measured by Li-COR6800 photosynthetic analyzer during the growth period.Then the PetC gene involved in the photosynthetic pathway was isolated by RT-qPCR,and comprehensive bioinformatics analysis was conducted by online tools.Furthermore,the expression patterns of PetC gene in different tissues and its dynamic expression in leaves of different development stages in K.paniculate were detected using RT-qPCR.Meanwhile,the correlation between KpPetC gene expression and net photosynthetic rate was analyzed.Additionally,an overexpression vector containing tandem KpPetC and eGFP with P2A elements was also constructedand and carried on ectopic genetic transformation in 84K poplar.The results showed that the net photosynthetic rate and transpiration rate of K.paniculata‘Jinye’were generally downregulated,while the intercellular CO2 concentration was significantly increased.These results indicated that the decreasing of photosynthetic rate in K.paniculata‘Jinye’was mainly caused by non-stomatal limitation.The strong light and high temperature in July might damage the photosynthetic elements of K.paniculata‘Jinye’,resulting in serious inhibition of photosynthesis,and the tolerance to light of K.paniculata‘Jinye’was weakened.The results of RT-qPCR assay revealed that KpPetC presented constitutive expression patterns in different tissues,but high abundant transcripts detected in leaf,and its expression in K.paniculata leaves was significantly higher than that in K.paniculata‘Jinye’in differe
作者
鲁海琳
吴茹茜
安新民
LU Hailin;WU Ruqian;AN Xinmin(State Key Laboratory of Tree Genetics and Breeding,National Engineering Research Center of Tree Breeding and Ecological Restoration,Advanced Innovation Center for Tree Breeding by Molecular Design,Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants of Ministry of Education,Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration,College of Biological Sciences and Technology,Beijing Forestry University,Beijing 100083,China)
出处
《中国细胞生物学学报》
CAS
CSCD
2024年第5期913-927,共15页
Chinese Journal of Cell Biology
基金
国家自然科学基金(批准号:31870652)资助的课题。
关键词
锦叶栾
光合作用
非气孔限制
PetC
基因克隆
表达分析
遗传转化
Koelreuteria paniculata‘Jinye’
photosynthesis
non-stomatal limitation
PetC
gene clone
expression analysis
genetic transformation
