2A proteinase of human rhinovirus cleaves cytokeratin 8 in infected HeLa cells.
Rhino- and enteroviruses encode two proteinases, 2A and 3C, which are responsible for the processing of the viral polyprotein and for cleavage of several cellular proteins. To identify further targets of the 2A proteinase of human rhinovirus serotype 2 (HRV2), an in vitro cleavage assay followed by two-dimensional electrophoresis was employed. Cytokeratin 8, a member of the intermediate filament group of proteins, was found to be proteolytically cleaved in vitro by the 2A proteinase of HRV2 and of coxsackievirus B4 and in vivo during HRV2 infection of HeLa cells. The cleavage results in removal of 14 amino acids from the N-terminal head domain of cytokeratin 8. However, other intermediate filament proteins (cytokeratins 7 and 18 and vimentin) were not cleaved in the course of the HRV2 infection. Compared with the processing of the eucaryotic translation initiation factors 4GI and 4GII, cleavage of cytokeratin 8 occurs late in the infection cycle at the time of the onset of the cytopathic effect.
Seipelt
J
J
Institute of Medical Biochemistry, Division of Biochemistry, University of Vienna, Dr. Bohrgasse 9/3, A-1030 Vienna, Austria.
Liebig
H D
HD
Sommergruber
W
W
Gerner
C
C
Kuechler
E
E
D015153:Blotting, Western; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D039603:Eukaryotic Initiation Factor-4G; D006367:HeLa Cells; D006801:Humans; D007633:Keratins / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D010446:Peptide Fragments / Q000378:metabolism; D010448:Peptide Initiation Factors / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D039102:Poly(A)-Binding Proteins; D011485:Protein Binding; D016601:RNA-Binding Proteins / Q000378:metabolism; D012229:Rhinovirus / Q000201:enzymology*; D013997:Time Factors; D014746:Vimentin / Q000737:chemistry / Q000378:metabolism; D014764:Viral Proteins
C113920:EIF4G1 protein, human; D039603:Eukaryotic Initiation Factor-4G; D010446:Peptide Fragments; D010448:Peptide Initiation Factors; D010455:Peptides; D039102:Poly(A)-Binding Proteins; D016601:RNA-Binding Proteins; D014746:Vimentin; D014764:Viral Proteins; D007633:Keratins; D003546:Cysteine Endopeptidases; C057400:picornain 2A, Picornavirus