Fig. 3
From: Translation control of Enterovirus A71 gene expression
The regulatory roles of cellular IRES trans-acting factors (ITAFs) in EV-A71 translation. The brown arrow indicates that MINK is phosphorylated after EV-A71 infection. Phosphorylation of MINK activates p38 MAPK kinase pathway, which stimulates the export of hnRNP A1 from the nucleus into the cytoplasm, where hnRNP A1 binds to domains II and VI of EV-A71 IRES and then recruits the ribosome to promote viral IRES-mediated translation. Similarly, hnRNP A2 can replace hnRNP A1 to promote viral IRES-mediated translation. EV-A71 infection also activates nuclear Sam68, PCBP1/2, and PTB1 proteins to redistribute to the cytoplasm. Sam68, PCBP1/2, and PTB1 bind to different domains of EV-A71 IRES to promote viral translation. EV-A71 viral proteinase 2Apro can cleave FBP1 to generates a functional cleavage product, FBP11–371, and the cleavage product also acts to promote viral IRES-mediated translation. FBP11–371 acts additively with FBP1 to promote IRES-mediated translation and virus production. FBP1 activates viral IRES activity by competing with FBP2, which also binds to EV-A71 IRES and acts as a negative regulator of EV-A71 translation