A Preliminary Study On The Effect Of Protein Phosphorylation Of Tyrosine On Vigor Of Seeds In Different Parts Of Maize Ear

The seed is the most basic and important means of production in the agricultural production.The seeds directly affect the quality of agricultural production and the seed vigor is the important indicators to measure the sowing quality of seeds.High vigor seed has fast and neat germination,high resistance and obvious growth advantage and production potential.Therefore,revealing the mechanism of differences of seed vigor has important theoretical significance and potential application value for high vigor seed production and processing.Also,it has important practical significance for improving competitiveness of China's seed industry.Previous studies in our laboratory have found that seed vigor in different parts of maize ears is that central part is the highest and the basal part is the lowest.In this study,we studied the effects of phosphorylation on the seed vigor of different parts of maize ear from two aspects-protein kinase gene and phosphorylated protein.The main results are as follows:1.The amount of tyrosine phosphorylated protein in the central part of the swelling 24 h seed protein was higher than that of the upper part in the range of 55-72 KD.2.Through the analysis of Western blot and MS found the protein.It was not phosphorylated in the upper part but it was phosphorylated in the middle and analysis of KEGG pathway showed that P93805 is a key enzyme phosphoglucomutase in the process of Glycolysis.Phosphorylation level differences of phosphoglucomutase may produce differences in energy between upper part and middle,thereby they can affect the seed vitality.3.We found that the promoter region not only has the TATA-box and CAAT-box promoter consensus sequence,but also has regulatory domains related to light response,low temperature response,stress response,the development and hormone by bioinformatics analysis of promoter's cis element of protein tyrosine kinase gene-GRMZM2G076423.The gene was predicted to encode 377 amino acids and molecular weight prediction of protein was 42.28 KD and isoelectric point was 7.12.Evolutionary analysis showed that the GRMZM2G076423 encoded protein was in a clade with the loc_os03g06330.1 encoded protein tyrosine kinase in rice,indicating the closest relationship between them.GRMZM2G076423 and loc_os03g06330.1 belong to subfamily.4.RT-PCR method was used to analyze the expression pattern of GRMZM2G076423.The results showed that the genes had different levels in different tissues;it had the highest expression level after 24h's imbibition;it was down regulated after the salt stress and drought stress.5.Through mutant and the insertion of mutant Mu transposon of 5 '-end of GRMZM2G076423,it was found that down regulated expression of this gene decreased seed vigor.