Ultrastructural Observation And Differential Proteomics Analysis Of Sporogenous And Nonsporogenous Sporocarp Of Pseudopeziza Medicaginis

Pseudopeziza medicaginis is the pathogen of alfalfa common leaf spot.This fungus overwintered the apothecium of the sporocarp formed by sexual reproduction,and in the spring of the next year,the ascospores were released from the apothecium for initial infection to complete the infection cycle.The structural characteristics of sporocarp are studied and the key proteins involved in the regulation of the development of sporocarp are analyzed,which provides the basis for further revealing the mechanism of sexual reproduction of fungi.In this experiment,to reveal P.medicaginis ' s formation mechanism from the perspective of cellular and proteomic.The ultrastructural characteristics of sporogenous and nonsporogenous sporocarp,the bioinformatics analysis of differential proteins and related proteins of sporogenous,nonsporogenous and early developmental sporocarp were studied by using the artificial culture sporocarp,and the photosynthetic physiology of sick alfalfa leaves was measured.The results are as follows:(I)The effect of P.medicaginis infection on photosynthesis in alfalfa leaves showed that the net photosynthetic rate and transpiration rate were significantly decreased,intercellular CO2 concentration was increased with the severity of common leaf spot.(2)The ultrastructural observation of P.medicaginis sporogenous and nonsporogenous colony showed that the sporogenous colony structure was intact,with obvious structure of apothecium,ascus mother cell,ascus,ascospore and paraphysis,and the structure of hyphae cells was dense and contained a lot of lipids.Only hyphae was observed in the nonsporogenous colony,and the cell structure was evacuated,and there was no obvious insoluble substance.(3)The studies of sporogenous colony,nonsporogenous colony and early developmental colony differential protein showed that 1125 proteins were identified in sporogenous colony,720 proteins were identified in nonsporogenous colony,and 1195 proteins were identified in early developmental colony.Compared with the proteins identified by the sporogenous colony and nonsporogenous colony,218 were identified only in the sporogenous colony,8 in the nonsporogenous colony.Relatived to sporogenous colony,52 up-regulated proteins and 112 down-regulated proteins in nonsporogenous colony.Compared with the proteins identified by the sporogenous colony and early developmental colony,36 were identified only in the sporogenous colony,70 in the early developmental colony.Relatived to sporogenous colony,33 up-regulated proteins and 41 down-regulated proteins in early developmental colony.Compared with the proteins identified by the nonsporogenous colony and early developmental colony,310 were identified only in the early developmental colony,25 in the nonsporogenous colony.Relatived to nonsporogenous colony,141 up-regulated proteins and 60 down-regulated proteins in early developmental colony.(4)The bioinformatics analysis of sporogenous colony,nonsporogenous colony and early developmental colony differential protein showed that in the sporogenous process of P.medicaginis,there were changes in the number of proteins,denaturation and renaturation,meiosis,increased synthesis of cytoskeleton and mitochondrial membrane,accompanied by the consumption of ATP,protein transfer and biosynthesis,involved in fatty acid biosynthesis,monosaccharide metabolism,nucleotide sugar metabolism,carbohydrate phosphorylation,glycol-alcohol metabolism and L-serine biosynthesis,protein targeting transport to the nucleus,ribonucleoprotein complex exportation from the nucleus,regulating the translation of precise,RNA transport,cellular senescence,mitochondrial inheritance,reactive oxygen metabolism,proteasome ubiquitin dependent protein catabolism and other biological processes.The synthesis of mitochondria was decreased,fatty acid and ATP were restricted,energy consumption was reduced,transcription process was affected,mitosis and pathogenicity were decreased in the non-sporulation colony.The utilization efficiency of ATP and glucose in sporogenous colony and nonsporogenous colony was different,which affected the development of P.medicaginis.The pathways of oxidative metabolism and fatty acid metabolism are different between early developmental colony and sporogenous colony.The utilization efficiency of glucose in early developmental colony and nonsporogenous colony is different.