A 60 kD heat-shock protein-like molecule interacts with the HIV transmembrane glycoprotein gp41.
The heat-shock protein hsp60 is typically found in mitochondria, but, in smaller amounts, also in the cell cytoplasm and associated with the cell membrane. Since heat-shock proteins are known to interact with a variety of molecules and since purified HIV-1 particles were described to contain hsp60 molecules, we tested the possibility that a previously described putative receptor for HIV transmembrane protein gp41 is identical to hsp60. The gp41-binding human protein P62 was purified from H9 and Raji cell lysates by a gp41-coupled affinity column. We could show crossreactivity of both polyclonal and monoclonal anti-hsp60 antibodies with the purified P62. In addition we analyzed binding of P18, a soluble gp41 fragment harboring the extracellular domain (Env aa539-684), to recombinant hsp60. Hsp60 bound well to P18-coated ELISA plates whereas HIV-1 surface protein gp120 induced no binding of hsp60. Preincubation of hsp60 with gp41 abolished the binding. The possible role of this molecule as a cofactor in the pathogenesis of HIV disease is discussed.
Speth
C
C
Institute for Hygiene and Ludwig Boltzmann-Institute for AIDS Research, Innsbruck, Austria. cornelia.speth@uibk.ac.at
Prohászka
Z
Z
Mair
M
M
Stöckl
G
G
Zhu
X
X
Jöbstl
B
B
Füst
G
G
Dierich
M P
MP
D001402:B-Lymphocytes / Q000166:cytology; D002478:Cells, Cultured; D018834:Chaperonin 60 / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism*; D015700:HIV Envelope Protein gp41 / Q000378:metabolism*; D015497:HIV-1 / Q000378:metabolism*; D006801:Humans; D009000:Monocytes / Q000166:cytology; D011485:Protein Binding; D013601:T-Lymphocytes / Q000166:cytology
D018834:Chaperonin 60; D006023:Glycoproteins; D015700:HIV Envelope Protein gp41