Correlation Analysis On Expression Of Acyltransferase Genes Related To Lipid Synthesis And Oil Content Of Kernel In Peanut(Arachis Hypogaea L.)

Peanut(Arachis hypogaea L.)is the important oil crops widely cultivated around the world,peanut oil is the major edible vegetable oils in China,and cultivating high oil varieties is an important target for peanut breeding research.Triacylglycerol(TAG),the main constituents of seed oil,is synthesized predominantly from one molecule of glycerol and three molecules of fatty acid through Kennedy pathway after three esterification reaction synthesis.The esterification reaction is catalyzed by three sequential acyltransferase,namely GPAT,LPAAT,DGAT.Previous studies have found that GPAT9,LPAAT,DGAT1-2 play an important role in the Kennedy pathway.In this study,peanut cultivars(lines)with different oil content were used as test materials,the expression levels of six genes(GPAT9-A,GPAT9-B,LPAAT-A,LPAAT-B,DGAT1-2A,DGAT1-2B)encoding three kinds of acyltransferases at different developmental stages were detected,the correlation between the expression of three types of acyltransferase gene and the oil content of kernel,and the expression of two subgenomic genes encoding the same acyltransferase were analyzed.The results of this study lay the foundation for the full utilization and transformation of acyltransferase gene regulation peanut oil and other oil crops,and it is of great reference value for peanut quality improvement.The main results were as follows:(1)With the growth and development of seed,the expression curve of three types of acyltransferase gene(expression pattern)was dominated by single peak and bimodal.There was no obvious correspondence between the expression curve of gene expression and the oil content of the c?ltivars.The expression level of high oil content species was significantly higher than that of low oil content species.(2)The expression level of GPAT9-B was higher than that of GPAT9-A.The expression level of LPAAT-A was higher than that of LPAAT-B,and the expression of DGAT1-2A was similar to that of DGAT1-2B.(3)There was a significant positive correlation between the total expression of the three types of acyltransferase gene and oil content of kernel.LPAAT had the highest correlation,DGAT1-2 followed,and GPAT9 had the lowest correlation.The expression levels of GPAT9-B,LPAAT-A,LPAAT-B,DGAT1-2A and DGAT1-2B were positively correlated with oil content of kernel.(4)The ratios of DGAT1-2B/GPAT9-A and DGAT1-2/GPAT9-A were significantly positively correlated with oil content,and the ratio of DGAT1-2B/LPAAT-B and DGAT1-2/LPAAT-B were significantly correlated with oil content.Indicating that the relative values of DGAT1-2 and GPAT9,LPAAT have an effect on seed oil content.(5)Four GPAT9 transgenic plants were obtained and the seeds of T0 plants were harvested,which provided the material for further study of GPAT9.