AIDSWEEKLY Plus, 20 May 1996 issue; Published by Charles Henderson, Publisher. Editorial & Publishing Office: P.O. Box 5528, Atlanta, GA 30307-0528 / Telephone: (800) 633-4931; Subscription Office: P.O. Box 830409, Birmingham, AL 35283-0409 / FAX: (205) 995-1588
Daniel J. DeNoon, Senior Editor

A small retroviral protein can be used to incorporate a foreign enzyme into virions, suggesting a new antiviral approach.

The protein, Vpx, is the product of the regulatory gene vpx found in the primate lentiviruses HIV-1, HIV-2, and SIV. The function of Vpx is not well understood, but it does not appear to be essential for virus replication.

Researchers In-Woo Park and Joseph Sodroski of the Dana- Farber Cancer Institute found that when the chloramphenicol acetyltransferase (CAT) enzyme is fused to Vpx from SIV, it is incorporated into SIV virions.

They reported their findings in the Journal of Acquired Immune Deficiency Syndromes and Human Retrovirology ("Targeting a Foreign Protein into Virion Particles by Fusion with the Vpx Protein of Simian Immunodeficiency Virus," JAIDS, 1996;11(4):341-350).

"Using a similar approach, it may also be possible to incorporate into immunodeficiency viruses foreign proteins that exert antiviral effects," Park and Sodroski reported.

"It appears that approximately 300 nucleotides of additional proviral length can be tolerated while retaining wild-type levels of virus replication in the cell lines examined."

In the T-cell lines in which the Vpx/CAT-containing viruses were grown, incorporation of the enzyme slowed but did not halt virus replication.

The researchers suggested that a more active enzyme than the CAT reporter gene would be required for antiviral activity.

"Disruption of virus replication requires more than just the presence of a large foreign protein within the virus particle," they wrote.

"It is possible that, in cell types such as primary lymphocytes and macrophages, in which Vpx and [the related protein] Vpr functions may be more important, the presence of even small amounts of a fusion protein such as the Vpx-CAT protein might be more disruptive of virus replication."

This work was supported by NIH Grants R01 A129333, P30 CA06516 (Cancer Center), P30 A128691 (Center for AIDS Research), and U01 A124845 (National Cooperative Drug Discovery Group) and a gift from the G. Harold and Leila Y. Mathers Charitable Foundation.

The corresponding author for this study is Joseph Sodroski, Department of Human Retrovirology, Dana-Farber Cancer Institute, Boston, Massachusetts.

Copyright (c) 1995 - Charles Henderson, Publisher. All rights Reserved. Permission to reproduce granted to AEGIS by Charles W. Henderson. Authorization to reproduce for personal use granted granted by C. W. Henderson, Publisher, provided that the fee of US$4.50 per copy, per page is paid directly to the Copyright Clearance Center, 27 Congress Street, Salem, Massachusetts 01970, USA.

960520
AW960508

Copyright © 1996 - Charles Henderson, Publisher. All rights Reserved. Permission to reproduce granted to AEGIS by Charles W. Henderson. Authorization to reproduce for personal use granted granted by C. W. Henderson, Publisher, provided that the fee of US$4.50 per copy, per page is paid directly to the Copyright Clearance Center, 27 Congress Street, Salem, Massachusetts 01970, USA.