Entry of Human Papillomavirus Type 16 by Actin-Dependent, Clathrin- and Lipid Raft-Independent Endocytosis

PLoS Pathogens

Mario Schelhaas¹  Patricia M. Day¹  Michael Holzer¹  Peter Blattmann²  Lena Kühling²  Bhavin Shah²  John T. Schiller³  Ari Helenius³ 

[1] Emmy-Noether Group ‚Virus Endocytosis', Institutes of Molecular Virology and Medical Biochemistry, University of Münster, Münster, Germany;Institute of Biochemistry, ETH Zurich, Zurich, Switzerland;Laboratory of Cellular Oncology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America

关键词: HPV-16;    HeLa cells;    Endocytosis;    SV40;    Cell membranes;    Small interfering RNAs;    Tyrosine kinases;    Influenza A virus;   

DOI  :  10.1371/journal.ppat.1002657

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

Infectious endocytosis of incoming human papillomavirus type 16 (HPV-16), the main etiological agent of cervical cancer, is poorly characterized in terms of cellular requirements and pathways. Conflicting reports attribute HPV-16 entry to clathrin-dependent and -independent mechanisms. To comprehensively describe the cell biological features of HPV-16 entry into human epithelial cells, we compared HPV-16 pseudovirion (PsV) infection in the context of cell perturbations (drug inhibition, siRNA silencing, overexpression of dominant mutants) to five other viruses (influenza A virus, Semliki Forest virus, simian virus 40, vesicular stomatitis virus, and vaccinia virus) with defined endocytic requirements. Our analysis included infection data, i.e. GFP expression after plasmid delivery by HPV-16 PsV, and endocytosis assays in combination with electron, immunofluorescence, and video microscopy. The results indicated that HPV-16 entry into HeLa and HaCaT cells was clathrin-, caveolin-, cholesterol- and dynamin-independent. The virus made use of a potentially novel ligand-induced endocytic pathway related to macropinocytosis. This pathway was distinct from classical macropinocytosis in regards to vesicle size, cholesterol-sensitivity, and GTPase requirements, but similar in respect to the need for tyrosine kinase signaling, actin dynamics, Na+/H+ exchangers, PAK-1 and PKC. After internalization the virus was transported to late endosomes and/or endolysosomes, and activated through exposure to low pH.

【 授权许可】

CC BY