异源表达异子蓬SaPEPC2基因提高烟草抗旱性和光合特性
Heterologous Expression of Suaeda aralocaspica SaPEPC2 Gene Improves Drought Resistance and Photosynthesis in Transgenic Tobacco
廖星鑫 1牛祎 1多兴武 1阿克也得力·居玛哈孜 1买热哈巴·阿不都克尤木热孜瓦尼姑丽·胡甫尔 1兰海燕 1曹婧1
作者信息
- 1. 新疆大学生命科学与技术学院,新疆生物资源基因工程重点实验室,生物学国家级实验教学示范中心,乌鲁木齐 830017
- 折叠
摘要
磷酸烯醇式丙酮酸羧化酶(PEPC)是C4光合关键酶,有助于植物在非生物胁迫下抵御逆境.异子蓬(Suaeda aralo-caspica)是一种无须Kranz结构即可在单细胞中高效执行C4光合作用的荒漠盐生植物,在C3作物遗传改良方面具有天然优势.以转异子蓬SaPEPC2基因烟草(Nicotiana tabacum)为材料,探讨了其抗旱功能和光合性能.结果表明,过表达SaPEPC2提高了烟草叶片持水能力,可保持叶绿素稳定;积累更多的渗透调节物质,增强了抗氧化酶活性,进而降低了植株体内的活性氧水平,减轻膜损伤程度;同时还增强了烟草抗旱相关基因和内源光合基因的表达,提高了PEPC活性和净光合速率,可能是促进了烟草体内的"类C4微循环"途径所致.研究结果为进一步利用异子蓬单细胞C4途径PEPC基因培育高光效抗逆农作物品种奠定了基础.
Abstract
INTRODUCTION:Phosphoenolpyruvate carboxylase(PEPC)is a key enzyme for C4 photosynthesis that help plants to resist adversity under abiotic stress.Suaeda aralocaspica,an annual halophyte,has gradually developed a single-cell C4 photosynthetic pathway by compartmentalizing a chlorenchyma cell into distal and proximal ends to delineate and form the four-carbon(C4)and three-carbon(C3)cycles through long term of evolution.This unique biochemical compartment-ation pattern holds promise for introducing"C4-like microcirculation"into C3 plants without establishing Kranz anatomy.RATIONALE:The PEPC gene act as an essential component of C4 photosynthesis,but few studies have reported on the PEPC gene in single cell C4-pathway species.To reveal the impact of the SaPEPC2 gene from S.aralocaspica on the photosynthetic performance and drought resistance of C3 plants,we evaluated the drought resistance function and pho-tosynthetic performance of transgenic tobacco(Nicotiana tabacum)overexpressing the SaPEPC2 gene driven by its own promoter(ProsaPEPC2::SaPEPC2)through physiological measurements and gene expression analysis methods.RESULTS:Our findings demonstrated that overexpressing the SaPEPC2 gene in tobacco improved leaf water retention,maintained chlorophyll stability,promoted the accumulation of osmotic adjustment substance,enhanced antioxidant en-zyme activities,reduced ROS levels,mitigated the extent of membrane damage,upregulated the expression of drou-ght-related and endogenous photosynthesis genes,and increased PEPC enzyme activity and net photosynthetic rate.CONCLUSION:In conclusion,overexpressing the SaPEPC2 gene likely facilitates the formation of a"C4-like microcircula-tion"pathway in tobacco.These results may provide the theoretical foundation for the potential utilization of the single-cell C4 pathway PEPC genes from S.aralocaspica to breed high light-efficiency and stress-resistant crop varieties.
关键词
单细胞C4植物/异子蓬/PEPC/抗旱性/光合作用Key words
single-cell C4 plant/Suaeda aralocaspica/PEPC/drought resistance/photosynthesis引用本文复制引用
基金项目
新疆维吾尔自治区自然科学基金(2022D01C95)
国家自然科学基金(32360066)
国家级大学生创新训练计划(202210755069)
出版年
2024
国家科技期刊平台
NSTL
万方数据