A Non-enveloped Virus Hijacks Host Disaggregation Machinery to Translocate across the Endoplasmic Reticulum Membrane

Mammalian cytosolic hsp110 family,in concert with the hsc70:j-protein complex,functions as a disaggregation machinery to rectify protein misfolding problems. here we uncover a novel role of this machinery in driving membrane translocation during viral entry. the non-enveloped virus sv40 penetrates the endoplasmic reticulum (er) membrane to reach the cytosol,a critical infection step. combining biochemical,cell-based,and imaging approaches,we find that the hsp110 family member hsp105 associates with the er membrane j-protein b14. here hsp105 cooperates with hsc70 and extracts the membrane-penetrating sv40 into the cytosol,potentially by disassembling the membrane-embedded virus. hence the energy provided by the hsc70-dependent hsp105 disaggregation machinery can be harnessed to catalyze a membrane translocation event. © 2015 ravindran et al.