Regulation of P38 and MKK6 kinase on heat-induced Raw264.7 cell apoptosis / 基础医学与临床

ABSTRACT

Objective To elucidate the role of P38 signaling pathway on heat-induced apoptosis in monocytic cell line Raw264.7.Methods Raw cells were transfected with constitutively active mutant MKK6b(E)and dominant negative mutant P38(AF),or the empty cloning vector pcDNA3 and apoptosis was detected by flow cytometric analysis.Results The ectopic expression of P38 mutant was confirmed by immunostaining with the antibody against the Flag-epitope tag.Expression of MKK6b(E)led to a marked increase in P38 kinase activity in transfected cells and induced a 4-fold increase in the number of apoptotic cells as compared to that in cultures of control transfected cells.Meanwhile the expression of MKK6b(E)increased the apoptotic rate of Raw cells induced by heat.In contrast,the dominant-negative mutant P38(AF)inhibited Raw cells apoptosis induced by heat.Conclusion The activation of the MKK6-P38 MAP kinase signaling pathway is required for heat-induced apoptosis in Raw264.7 cells.