Mycelial Enzymatic Activiation And Proteomics Of Magnaporthe Oryzae In Nitrogen Starvation

Magnaporthe oryzae causing the rice blast disease,is one.of the important plant pathogenic fungi.It is also can infect other species of Gramineae.Many researches focus on the complex interaction between rice and M.oryzae.Previous studies have shown that nitrogen-starvation is one of the major environmental stress in the interaction,many secreted proteins,involved in interaction between rice and M.oryzae,produced from cultured in nitrogen-starvation medium.It is unclear that the molecular mechanism of M oryzae mycelium growth in nitrogen-starvation.Proteomic methods and techniques were used to analyze the variation of proteome in CH-63 mycelium with cultured in complete medium and nitrogen-starvation medium,in order to search the different proteins related closely to nitrogen-starvation and to investigat the function.Meanwhile we analyzed the activities of protective enzymes under two different conditions to know the adaptive mechanism of M.oryzae in nitrogen-starvation.Mycelial proteins were separated using rotofor,2-DE and mass spectrometry.By means of these experiments,it is fundamentally understandable that the difference of Mycelial proteins are expressed under the different nutrient medium.The main results are followed:1、The activity of protective enzymes were acquired:The activity of CAT、POD、SOD raised rapidly in the pre-6 to pre-9 hours of treatment.And after that they dropped gradually.MDA increased in pre-12 hours and later slightly declined.Both protective enzymes and MDA were higer than those in control,which indicated that the cell membrane of M.oryzae mycelium was injured.However,M.oryzae possesses strong adaptability in nitrogen-starvation to a certain extend and achieve a new balance.2、Through optimization of the extraction method of protein samples,the strips range of options,and the adjustment of the sample volume,The 2-DE system applying to mycelium protein of M.oryzae was established,The high-resolution 2-DE maps of mycelium protein were obtained through improved method,which was enough to fulfill the mass spectrometry.3.Spots of 975 ± 70 and 1169 ± 90 were detected on the 2-DE maps with CH-63 mycelium with cultured in complete medium and nitrogen-starvation medium.Fourty-nine changed protein spots were found in nitrogen stress conditions.Changed protein spots were identified by MALDI-TOF-MS/MS,and 43 proteins were successfully recognized.Thirty-seven spots had functional description and 6 spots were unknown protein.Proteins with functional description involved development,metabolizable action,biosynthesis,biologic process and so on.It shows that there may be kinds of proteins and enzymes joined in the control of M.oryzae in nitrogen-starvation.