Effects On Phosphorylation Levels Of JNK,p38 And ERK Proteins In Frankliniella Occidentalis From Low Temperature Stresses And Beauveria Bassiana Infection

In this study,we identified and expressed MAPK-related proteins genes of F.occidentalis,surveyed its expression in various developmental stages and its functional activation in responses to low-temperature or of B.bassiana interaction,in order to further study more MAPK-related proteins of F.occidentalis,and understand the molecular mechanisms underlying their remarkable adaptability of F.occidentalis.The main results of the paper are as follows:1.Analyses and expression of MAPK-related protein genes of F.occidentalisThe results showed that the cDNA of F.occidentalis JNK consists of 1191bp open reading frame(ORF)which encodes 396 amino acids.There is a typical S_TKc domain in the 18-314 amino acids with a phosphorylation activation group TPY,and the molecular weight of the mature protein is predicted to be 45.34kDa;The cDNA of p38 consists of 840bp open reading frame(ORF)which encodes 279 amino acids.There is a typical S_TKc domain in the 20-270 amino acids with a phosphorylation activation group TGY,and the molecular weight of the mature protein is predicted to be 31.64kDa;The cDNA of ERK consists of 987bp open reading frame(ORF)which encodes 328 amino acids.There is a typical S_TKc domain in the 2-276 amino acids with a phosphorylation activation group TEY,and the molecular weight of the mature protein is predicted to be 38.34kDa;Amino acid sequence analyses indicate that these MAPK proteins are highly conservaed among different species,and each has a strictly conserved dual phosphorylation motif TPY?TPY and TEY.The high similarity confirms that commercial antibodies against mammalian kinases can likely be used successfully in F.occidentalis.2.Effects to different temperatures on MAPK phosphorylation of F.occidentalisTo test effects of temperatures on MAPK signaling pathway,we treated F.occidentalis under five temperatures ranging from-13 to 39?.By using Western blot to test and analyses.The results showed that low temperature stress activated F.Occidentalis JNK and p38 signaling pathway,and their phosphorylation increased in 10min at 0?,while no significant change was observed in ERK.It is speculated that JNK and p38 may be related to stress response to low temperature pressure.3.Effects to B.bassiana interaction on MAPK phosphorylation of F.occidentalisBy using quantitative real-time PCR and the comparative 2-??ct method,JNK,p38 and ERK gene expression profiles of B.bassiana interaction in F.occidentalis were measured.The activation of MAPKs in Frankliniella occidentalis was examined with anti-phospho-JNK,anti-phospho-p38,anti-phospho-ERK,Tatol-phospho-p3 8,Tatol-phospho-p38,Tatol-phospho-p38 antibodies.Compared with the control group,there are significant differences in the relative 3 genes expression.After the fungal infection of B.bassiana,the expression level of JNK and p38 in F.occidentalis was up-regulated in three stages,ho weverthe higher expression level was monitored in infected pupal than in others.The results showed JNK in pupal had the highest expression at 7.25 times in 36h.The results showed p38 in pupal had the highest expression at 9.54 times in 48h.But ERK in F.occidentalis was down-regulated in three stages.To detecte the MAPK phosphorylation in adults which has been infected by B.bassiana at 12,24,36 48h bying using Western blot technology.The results showed that after infection the phosohoryated of the JNK and p38 in F.occidentalis has increased.It can be observed that the phosphorylation of JNK and p38 increased significantly in 24h and the maximum at 48h.However,there was no significant change in ERK phosphorylation protein.