Novel recognition sequence of coxsackievirus 2A proteinase.
Coxsackievirus B1 (CVB1) 2A proteinase (2A(pro)) is a cysteine proteinase that cleaves the viral monocistronic polyprotein between the C-terminus of the VP1 region and the N-terminus of the 2A region, and also shuts off translational initiation in host cells by cleavage of eukaryotic initiation factor 4G (eIF4G) isoforms. We expressed in Escherichia coli a series of fusions in which various C-terminal fragments of VP1 were linked to the N-terminus of 2A(pro), and we also employed site-directed mutagenesis to introduce mutations of several amino acid residues. Our results showed that the presence of the C-terminal three amino acid residues of VP1 at the N-terminus of 2A(pro) is sufficient for specific self-cleavage between VP1 and 2A(pro) to generate mature 2A(pro), but the P4 amino acid also plays an important role. We further found that 2A(pro) cleaves the amino acid sequence Leu-Val-Pro-Arg-( *)Gly-Ser (LVPRGS motif), which is the target sequence of thrombin.
Muto
Shinji
S
Department of Microbiology, St. Marianna University School of Medicine, Kawasaki 216-8511, Japan.
Miyoshi
Hiroshi
H
Nishikawa
Hiroyuki
H
Nakashima
Hideki
H
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D004770:Enterovirus / Q000201:enzymology*; D039603:Eukaryotic Initiation Factor-4G / Q000378:metabolism; D006639:Histidine; D016297:Mutagenesis, Site-Directed; D020815:Polyproteins / Q000737:chemistry / Q000378:metabolism; D020033:Protein Isoforms / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D013379:Substrate Specificity; D013917:Thrombin; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D039603:Eukaryotic Initiation Factor-4G; D020815:Polyproteins; D020033:Protein Isoforms; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; C033223:polyhistidine; D006639:Histidine; D013917:Thrombin; D003546:Cysteine Endopeptidases; C057400:picornain 2A, Picornavirus