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Jun 4, 1996 - gpl20 on its association with calnexin, folding, and intracellular transport. YAN LI*, JOHN J. M. BERGERONt, LIZHONG Luo*, WEI-JIA Out, ...
Proc. Natl. Acad. Sci. USA Vol. 93, pp. 9606-9611, September 1996 Cell Biology

Effects of inefficient cleavage of the signal sequence of HIV-1 gpl20 on its association with calnexin, folding, and intracellular transport YAN LI*, JOHN J. M. BERGERONt, LIZHONG Luo*, WEI-JIA Out, DAVID Y. THOMASt, AND C. YONG KANG*§ *Department of Zoology, Faculty of Science and Department of Microbiology and Immunology, Faculty of Medicine, The University of Western Ontario, London ON, Canada N6A 5B7; tDepartment of Anatomy and Cell Biology, McGill University, Montreal QC, Canada H3A 2B2; and tEukaryotic Genetics Group, Biotechnology Research Institute, National Research Council of Canada, 6100 avenue Royalmount, Montreal QC, Canada H4P 2R2

Communicated by Max Summers, Texas A&M University, College Station, TX, June 4, 1996 (received for review April 4, 1996)

ABSTRACT The HIV-1 envelope glycoprotein gpl20 displays inefficient intracellular transport, which is caused by its retention in the endoplasmic reticulum. Coexpression in insect cells (Sf9) of mV-1 gpi20 with calnexin has shown that their interaction was modulated by the signal sequence of mHV-1 gpl20. gp120, with its natural signal sequence, showed a prolonged association with calnexin with a t/2 of greater than 20 min. Replacement of the natural signal sequence with the signal sequence from mellitin led to a decreased time of association of gpi20 with calnexin (tt/2