Cleavage of dengue virus NS1-NS2A requires an octapeptide sequence at the C terminus of NS1.
The length of amino acid sequence at the NS1-NS2A juncture of dengue virus that is required for specific cleavage effected by the cis-acting function of NS2A was identified by deletion analysis. Recombinant DNA sequences of NS1-NS2A, each containing a deletion in NS1 followed by a sequence of 3 to 20 amino acids at the C terminus of NS1 preceding the cleavage site, were constructed and expressed with vaccinia virus as a vector. The NS1 product of recombinant vaccinia virus-infected cells was immunoprecipitated and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The occurrence of cleavage between NS1 and NS2A was indicated by the appearance of shortened NS1. Failure to cleave this site yielded a large NS1-NS2A fusion protein. This analysis indicated that a minimum length of eight amino acids at the NS1 C terminus preceding the NS1-NS2A juncture is required for cleavage to take place. Comparison of this eight-amino-acid sequence of the NS1 C terminus of dengue type 4 virus with the analogous sequences of 12 other flaviviruses suggests that the consensus cleavage site sequence is as follows: (table; see text)
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Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland 20892.
Lai
C J
CJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D002213:Capsid / Q000235:genetics / Q000378:metabolism*; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D003716:Dengue Virus / Q000235:genetics / Q000378:metabolism*; D005814:Genes, Viral; D006026:Glycoside Hydrolases; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D010447:Peptide Hydrolases / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013379:Substrate Specificity; D014616:Vaccinia virus / Q000235:genetics; D014758:Viral Core Proteins / Q000235:genetics / Q000378:metabolism*; D017361:Viral Nonstructural Proteins
D015345:Oligonucleotide Probes; D011993:Recombinant Fusion Proteins; D014758:Viral Core Proteins; D017361:Viral Nonstructural Proteins; D006026:Glycoside Hydrolases; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D010447:Peptide Hydrolases