Molecular cloning of a novel chaperone-like protein induced by rhabdovirus infection with sequence similarity to the bacterial extracellular solute-binding protein family 5.
Previously we demonstrated that a novel stress protein is induced in fish cells by the infection of a fish rhabdovirus (Cho W. J., Cha, S. J., Do, J. W., Choi, J. Y., Lee, J. Y., Jeong, C. S., Cho, K. J., Choi, W. S., Kang, H. S., Kim, H. D., and Park, J. W. (1997) Biochem. Biophys. Res. Commun. 233, 316-319). In this paper, we present the molecular cloning and characterization of a gene encoding this protein named virus-inducible stress protein (VISP). The VISP was purified partially by immunoprecipitation using a monoclonal antibody against the VISP and further purified by the electroelution from a SDS-PAGE gel. The protein was subjected to internal protein sequencing, and the sequence of three peptides was determined. Degenerate oligonucleotides based on the three peptide sequences were used to screen a cDNA library from rhabdovirus-infected CHSE-214 fish cells, and a cDNA of a 2193-bp open reading frame encoding the VISP with 730 amino acid residues (M(r) = 79.84) was identified. Whereas the nucleotide sequence of VISP shows no similarity with other genes in the GenBank(TM), the amino acid sequence of the VISP has similarity with the bacterial extracellular solute-binding protein family 5 (SBP_bac_5) that is proposed to have chaperone activity. Thus, we explored whether the VISP also had chaperone-like activity. Purified recombinant VISP expressed in Escherichia coli promoted the functional folding of alpha-glucosidase after urea denaturation and also prevented thermal aggregation of alcohol dehydrogenase. These results suggest that the VISP has amino acid sequence similarity with SBP_bac_5 and that it has chaperone activity that may play a role in virus infection.
Department of Biological Sciences and Immunomodulation Research Center, University of Ulsan, Korea.
Wha Ja
WJ
Cho
Won Joon
WJ
Yoon
Chang Hoon
CH
Moon
Seung Ju
SJ
Cha
Hebok
H
Song
Hong Rae
HR
Cho
Soo Jin
SJ
Jang
Dae Kyun
DK
Chung
Choon Soo
CS
Jeong
Jeong Woo
JW
Park
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D001483:Base Sequence; D001692:Biological Transport; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000302:isolation & purification; D018832:Molecular Chaperones / Q000737:chemistry / Q000235:genetics* / Q000502:physiology; D008969:Molecular Sequence Data; D017510:Protein Folding; D018353:Rhabdoviridae Infections / Q000378:metabolism*; D014158:Transcription, Genetic; D000520:alpha-Glucosidases / Q000096:biosynthesis / Q000737:chemistry
D001426:Bacterial Proteins; D018076:DNA, Complementary; D018832:Molecular Chaperones; D000520:alpha-Glucosidases