ABSTRACT
Objective:To investigate the effect of Rab7 on cytokine induced by TLR7 (Toll like receptor-7) R848 activated in Raw264.7,and discusses the influence of Rab7 on MAPK signal transduction.Methods: TLR7 downstream cytokines such as TNF-α,IL-6,IFN-α,IFN-β and IP-10 activated by R848 were detected through Q-PCR in Rab7 silenced mouse macrophages,and then analysis of phosphorylation of MAPK determined with Western blot showed the effect of Rab7 on signal transduction of MAPK.Results: Rab7 inhibit production of cytokine activated by TLR7,and also,Rab7 had an inhibitory effect on MAPK signal pathway.Conclusion: The experimental results further illustrate that the Rab7 is the TLR7 signal transduction pathway negative regulatory factor,and to participate in MAPK signaling pathway.
ABSTRACT
Objective:To establish cell lines stably expressing Rab5a and its the inactive mutant Rab5aN133I,analyze the effect of Rab5a on the expression of cytokines in LPS-stimulated RAW264.7 cells .Methods:RAW264.7 cells were transfected with Rab5a and its inactive mutant vector Rab5a N133I separately,and then screened by G418.Rab5a stable expressing cell lines were identified by Real time-PCR.The growth of the stable cell lines was analyzed by MTT assay.After the stable cell lines were stimulated by LPS for different time periods,the expression of iNOS,TNF-αand IL-6 was detected.Results:Rab5a and Rab5aN133I transfection resulted in elevated Rab5a mRNA expression compared with the control cells ( P<0.05 ).Rab5a overexpression enhanced the proliferation of RAW264.7 cells.However,the proliferation of Rab5aN133I cells was significantly slower than the control cells ( P<0.05).Overexpression of Rab5a promoted LPS-induced production of iNOS,TNF-αand IL-6 in RAW264.7 cells (P<0.01). Conversely,overexpression of Rab5aN133I abolished the stimulating effects of Rab5a.Conclusion: Rab5a promoted LPS-induced expression of iNOS,TNF-αand IL-6 in RAW264.7 macrophages in a GTP-binding ability-dependent manner.