Interaction Between YL Protein And ZmPEPCs In Maize And Its Effect On Enzyme Activity

Maize（Zea mays L.）is one of the important crops,which plays an important role in national economy and biological research.Mutants are important materials for studying plant growth and development.In this study,candidate gene GRMZM2G095254（yl gene）of yellow leaf mutant（yellow leaf,yl）and Weaky mutant（Weaky）was studied.Based on the interaction between YL protein and C₄PEPC,C₃PEPC was previously verified in the laboratory.This study explored the interaction between Root-PEPC and YL protein,and studied the influence of the interaction between YL protein and Zm PEPCs on their enzymatic properties.The main results are as follows:1.Comparing the amino acid sequences of C₄PEPC,C₃PEPC,Root-PEPC and Bacterial-PEPC in maize,it was found that the amino acid sequences of the three plant type PEPCs have high homology,but the amino acid sequences of plant type PEPCs and bacterial type PEPCs have low homology,and there are significant differences in gene structures.The structural differences of the four PEPCs amino acid sequences may be related to the differences in the catalytic and regulatory properties of their enzymes.2.Yeast two-hybrid and BiFC experiments have shown that there is interaction between Root-PEPC and YL protein,with interaction sites located in the nucleus and weak interaction signals on the cell membrane.3.YL protein,C₃PEPC,C₄PEPC and Root-PEPC were expressed in Escherichia coli.The enzyme activity of Zm PEPCs was measured at different temperatures with YL protein.The results showed that the enzyme activities of C₃PEPC,C₄PEPC and Root-PEPC were all highest at 30℃.After adding YL protein and ATP simultaneously to the PEPC enzyme activity measurement system,the enzyme activity of Zm PEPCs was significantly decreased under various temperature conditions.YL protein can inhibited the enzyme activity of Zm PEPCs,and the inhibitory effect of YL protein was an active process,and its activation required ATP driving.4.Comparing the PEPC enzyme activity of the leaves in the two-leaf stage and three-leaf stage of maize materials,it was found that the PEPC enzyme activity of the leaves in three-leaf stage of the OE material with yl gene was significantly higher than that in the two-leaf stage.The PEPC enzyme activity of the KO material with yl gene in three-leaf stage was significantly higher than that in two-leaf stage.This study laid the foundation for elucidating the interaction mechanism between YL protein and Zm PEPCs,as well as the regulation of this interaction on maize growth and development,and C₄ metabolism pathway.