Heat Shock Cognate Protein 70 Is a Cell Fusion-Enhancing Factor but Not an Entry Factor for Human T-Cell Lymphotropic Virus Type I

doi:10.1006/bbrc.1999.1028

Biochemical and Biophysical Research Communications

Volume 261, Issue 2, 2 August 1999, Pages 357-363

https://doi.org/10.1006/bbrc.1999.1028 Get rights and content

Abstract

Heat shock cognate protein 70 (HSC70) has been shown to bind to the peptide corresponding to amino acids 197 to 216 of human T-cell lymphotropic virus type I (HTLV-I) envelope protein, gp46, and an anti-HSC70 monoclonal antibody (mAb) inhibits HTLV-I-induced syncytium formation. These findings suggest that HSC70 is necessary for the entry of HTLV-I into its target cells. Here we showed that HSC70 directly binds to gp46 by co-immunoprecipitation of HSC70 and gp46 from HTLV-I-producing human T-cell lysate. However, transduction of human HSC70 cDNA into BaF3 cells, which were found to be highly resistant to HTLV-I infection, did not support the HTLV-I entry, and HSC70 expressed in NIH3T3 cells, which were found to be almost resistant to syncytium formation upon cocultivation with HTLV-I-producing cells but sensitive to infection with cell-free HTLV-I, enhanced cell fusion induced by HTLV-I-producing cells, but did not enhance the entry of cell-free HTLV-I into these cells. The mAb against HSC70 inhibited syncytium formation in NIH3T3 cells expressing HSC70, but showed little effect on infection of these cells with cell-free HTLV-I. These findings indicate that HSC70 markedly enhances syncytium formation induced by HTLV-I but does not facilitate HTLV-I entry into target cells.

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Citation Excerpt :
Due to the limited coding capacity of virus genomes, viruses are obligate intracellular parasites that subvert an array of cellular factors or processes to complete their replication cycles. In this regard, it is interesting to note the involvement of heat shock proteins (Hsps) at different stages of the infectious cycle, including cell entry (Fang et al., 1999; Guerrero et al., 2002), uncoating (Niewiarowska et al., 1992), replication (Liu et al., 1998; Park et al., 2003), gene expression (Gallie, 2002; Kampmueller and Miller, 2005), encapsidation (Satyanarayana et al., 2004) and virion release (Vasconcelos et al., 1998; for a review see Xiao et al., 2010). Hsps are a diverse group of proteins, many of which are chaperone molecules that facilitate protein folding, trafficking, prevention of aggregation and degradation by proteolysis in cells subjected to heat and other environmental insults (Gething and Sambrook, 1992; Young et al., 2004; Bukau et al., 2006).
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¹: Corresponding author. Fax: 81-27-220-8006. E-mail: [email protected].

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Biochemical and Biophysical Research Communications

Regular ArticleHeat Shock Cognate Protein 70 Is a Cell Fusion-Enhancing Factor but Not an Entry Factor for Human T-Cell Lymphotropic Virus Type I

Abstract

Cell

Virology

Neurol. Clin.

Cell

Virology

Biochem. Biophys. Res. Commun.

Biochem. Biophys. Res. Commun.

FEBS-Lett.

Genomics

Cell

J. Virol.

Eur. J. Immunol.

Int. J. Cancer

Science

Nature

Nature

J. Virol.

J. Virol.

Nucleic Acids Res.

Int. J. Cancer

J. Virol.

Heat shock protein 40 (Hsp40) plays a key role in the virus life cycle

Quantitative proteome profiling of respiratory virus-infected lung epithelial cells

A new sensitive and quantitative HTLV-I-mediated cell fusion assay in T cells

Fbs2 Is a New Member of the E3 Ubiquitin Ligase Family That Recognizes Sugar Chains

The virus-chaperone connection

Host cell stress response as a predictor of COVID-19 infectivity and disease progression

Regular Article
Heat Shock Cognate Protein 70 Is a Cell Fusion-Enhancing Factor but Not an Entry Factor for Human T-Cell Lymphotropic Virus Type I