Research On The Biological Function And Regulatory Mechanism Of MiR394 In The Interaction Between Plant And Botrytis Cinerea

Plants are easily affected by the surrounding environment during growth and development.Gray mold caused by the pathogen Botrytis cinerea is one of the major factors that are harmful to tomato production.According to the results of our research group,mi R394 is responded to the infection by B.cinerea.Over-expression mi R394 transgenic A.thaliana and lcr mutants were used to clarified the function and mechanism of mi R394 in response to B.cinerea in tomato.The main researches are as follows:1.Inoculated tomato with B.cinerea and the samples were collected at different time.q RT-PCR results showed that mi R394 was involved in the defense of B.cinerea.2.In order to further determine the functional role of mi R394,we inoculated overexpressing mi R394 transgenic plants and lcr mutant Arabidopsis thaliana with B.cinerea.It is finding that leaf surface of overexpression-mi R394 plants and lcr mutants appear larger lesion size compared to the wild type,and then integrated trypan blue staining showed that A.thaliana mi R394 exists a direct effect on LCR.MiR394 acts as a negative regulator of Arabidopsis defense against B.cinerea making plants more sensitive to B.cinerea.3.Overexpression of mi R394 in the transgenic lines affect expression of other stressrelated miRNAs.The q PCR results showed that the expression levels of mi R156,mi R168,and mi R172 were up-regulated in all lines,except for mi R159.It is suggesting that these miRNAs have potentially association with mi R394.4.The expression of seven related protein-coding genes in the process of miRNA synthesis and action was detected in the transgenic lines.There are three genes upregulated,including DDL,DRB4 and AGO1.It is indicated that the over-expression of mi R394 has a positive feedback effect on these genes.5.Two plant hormone regulation pathways: the four key genes in the Jasmonic Acid / Salicylic Acid pathway were detected in transgenic plants and the lcr mutants.Both higher levels of mi R394 and lower levels of LCR lead to increased expression of PDF1.2 and PR4,which may also serve as a potential influencing factor,making mi R394/LCR more sensitive to infection by B.cinerea.6.It is reported that mi R394 is involved in plant abiotic stress.We verified and obtained consistent results,indicating that over-expression of mi R394 enhances A.thaliana drought-tolerant and salt-sensitiveness.In this research,we have investigated the function of mi R394/LCR in resistance to B.cinerea,and then identified the mi R394/LCR is associated with JA/SA pathway genes.These studies will build the foundation for further clarifying the regulatory mechanism of mi R394/LCR and the molecular control of B.cinerea.