木薯SDH蛋白的序列分析及其与MeH1.2关系的研究OA北大核心CSTPCD

[Objective]Sorbitol dehydrogenase(SDH)plays an important role in regulating the conversion between fructose and sorbitol in Roseviaceae plants,and also participates in plant resistance to stress.The study on the function of MeSDH gene may provide a theoretical basis for cultivating cassava germplasm with high yield and resistance to stress.[Method]MeSDH gene was cloned using'SC124'cDNA as template,and the tissue specificity of MeSDH gene and its response pattern to drought,low temperature,PEG and ABA were analyzed by quantitative real-time PCR(RT-qPCR).MeH1.2 was used as bait to screen the mixed yeast cDNA library of cassava under drought and low temperature.Yeast two hybridization(Y2H)point-to-point and bimolecular fluorescence complementation(BiFC)experiments were further used to confirm the relationship between target proteins.[Result]The CDS length of MeSDH gene cloned from'SC124'cDNA is 1092 bp,encoding 364 amino acids,and the sequence shows no difference with it in the database.MeSDH protein contains catalytic Zn binding site,NADP binding site and structural Zn binding site,belonging to the MDR superfamily.MeSDH protein is localized in the nucleus by transforming tobacco leaves.The expression of MeSDH gene is decreasing in the order of functional leaves,young leaves,fibrous roots and stems.The expression of MeSDH is up-regulated in the cassava leaves treated with drought,low temperature and PEG,and significantly up-regulated in the cassava leaves and roots treated with ABA.Yeast library screening,Y2H point-to-point and BiFC experiments confirm the interaction between MeH1.2 and MeSDH.[Conclusion]MeSDH gene is up-regulated in response to various stresses,and probably MeSDH and MeH1.2 work together.