Different Responses Of Rice DNA Methyltransferase Mutants Under Ozone Stress And Mining Of Instinct Response Genes

The continuous increase of the concentration of the straton ozone（O₃）causes varying degrees of damage to the quality and yield of food,and seriously threatens global food safety.Therefore,the effect of ozone on crops cannot be ignored.important.As one of the world’s most important grain crops in the rice（Oryza Sativa L.）,it has become a model plant for crop function genome research to explore its molecular mechanism for environmental coercion（such as ozone）and cultivate new types of anti-inverse rice varieties.It is a issue that scientists pay attention to.Therefore,reasonable use of apparent genetic mutations to create a group that can resist adversity and improve production can provide new ideas for improvement of crop improvement.DNA methylation is one of the most important and most important ways to study it.CG methylation,as the most common type of cytopine in rice,is mainly maintained by DNA methyl metastase 1（Methyltransferase 1）.The lack of MET1genes will cause random changes in the level of nailing of the plant whole genome and mode,thereby regulating growth and development by affecting gene expression.Therefore,in order to study whether the lack of the MET1 gene function can make the rice show the difference in response to ozone stress response and allow it to produce genes that can resist ozone（instinct ozone response genes）,this experiment selects the descendants of the Osmet1 mutant’s self-made offspring group For experimental materials,that is,Osmet1^+/-,Osmet1^+/+mutant,use the top box method（OTC）for the ozone concentration of 200 ppb for a 25-day continuous processing.Digging and studying the molecular mechanism of Osmet1 mutant body in response to ozone stress,and the following conclusions are obtained:1.The genotype identification identification of the Osmet1 mutant group was completed through specific PCR amplification,and a total of 130 Osmet1 mutants were detected,of which the genotype of 82 strains was"+/-"and the genotypes of 48strains were"+/+".2.Osmet1 mutant and rice during ozone treatment during the ozone treatment period,Japanese Qingye Wild Type（NIP-O₃）,conducted a survey Differences in agronomic traits screen out the relatively resistant Osmet1 mutant（Tr-met1）and relatively sensitive Osmet1 mutant（Ts-met1）.The results show that:the strong and weak anti-oxygen coercion capabilities are relatively resistant OSMET1 mutant（Tr-met1,19 single plants）>Rice Japanese Naruto Wild Type（NIP-O₃）>Relatively sensitive Osmet1 mutant（Ts-met1,18 Single plant）.3.The results of the transcription group analysis before ozone treatment show that compared with the relatively sensitive Osmet1 mutant group（s-met1）,the Chinese Communist Party has found 21 common expression genes in the relatively resistant Osmet1 mutant group（r-met1）,and they Very significant（P<0.01）is enriched in molecular functions such as acetylcel glucose metastase activity and NADH dehydrogenase activity.Among the molecular functions such as enzyme activity,oxidation reduction enzyme,combined with the expression trend analysis,it shows that during the normal growth and development stage,the r-met1 group is compared with the s-met1 group and the NIP-0d group.The expression regulation mode of catalytic sugar substance synthesis and plant body energy conversion has shown a downward trend.4.After ozone treatment,comparative analysis of the transcription of Tr-met1group and the Ts-met1 group found that there were 11 common difference expression genes in the Tr-met1 group in the Tr-met1 group.The response and growth and development of ozone stress finally screened the uniquely resisting ozone genes of 7Osmet1 mutants.These genes are very high（P<0.01）enriched in nitrogen metabolism,and significantly enriched（P<0.05）in the metabolic pathway of biomaba such as chloride and chlorophyll metabolism,secondary metabolism The group can resist the coercion by regulating the synthesis of its metabolic substances,photosynthetic effects,and the ability of nitrogen absorption to maintain their own growth and development5.By filtering the genes with obvious differences in the expression levels before and after ozone treatment,the two groups are screened,and it is excavated that the instinct type response gene Loc＿os09g11160 that can resist ozone due to mutations in the MET1 gene is tapped.Before the ozone treatment,the r-met1 group expression was significantly higher than the s-met1 group.After the ozone treatment,the Tr-met1group was activated and expressed.The difference between the MET1 group and the NIP-O₃group is higher than before the ozone treatment.Explain that Osmet1 mutant activates the expression of Loc＿os09g11160,which can actively respond to oxygen coercion.6.The specific differences of differential differences obtained from the two groups of confrontation and sensitivity are performed in real-time fluorescent quantitative PCR（q RT-PCR）verification,which is consistent with the expression trend in the transcription group sequencing results.In the comparison,the normal growth and development stage has shown a significant downward trend.After ozone treatment,the expression of the mutant group of Osmet1 mutant group is not significantly different.The difference between the two groups is not significant;The quantity will be significantly higher than other groups,indicating that the relatively resistant Osmet1 mutant group may resist ozone stress by stimulating gene expression.The above results are the theoretical basis for exploring the molecular mechanism of Osmet1 mutant to resist ozone,creating a theoretical basis for creating an anti-vivid genetic mutant group with resistance to ozone stress.