ACTIVATION OF THE JC VIRUS TAT-RESPONSIVE TRANSCRIPTIONAL CONTROL ELEMENT BY ASSOCIATION OF THE TAT PROTEIN OF HUMAN-IMMUNODEFICIENCY-VIRUS-1 WITH CELLULAR PROTEIN PUR-ALPHA
Cp. Krachmarov et al., ACTIVATION OF THE JC VIRUS TAT-RESPONSIVE TRANSCRIPTIONAL CONTROL ELEMENT BY ASSOCIATION OF THE TAT PROTEIN OF HUMAN-IMMUNODEFICIENCY-VIRUS-1 WITH CELLULAR PROTEIN PUR-ALPHA, Proceedings of the National Academy of Sciences of the United Statesof America, 93(24), 1996, pp. 14112-14117
JC virus is activated to replicate in glial cells of many AIDS patient
s with neurological disorders, In human glial cells, the human immunod
eficiency virus 1 (HIV-1) Tat protein activates the major late promote
r of JC virus through a Tat-responsive DNA element, termed upTAR, whic
h is a recognition site for cellular Pur alpha, a sequence-specific si
ngle-stranded DNA binding protein implicated in cell cycle control of
DNA replication and transcription, Tat interacts with two leucine-rich
repeats in Pur alpha to form a complex that can be immunoprecipitated
from cell extracts, Tat enhances the ability of purified glutathione
S-transferase-Pur alpha (GST-Pur alpha) to bind the upTAR element, Tat
acts synergistically with Pur alpha, in a cell-cycle-dependent manner
, to activate transcription at an upTAR element placed upstream of a h
eterologous promoter, Since Pur alpha is ubiquitously expressed in hum
an cells and since PUR elements are located near many promoters and or
igins of replication, the Tat-Pur alpha interaction mag be implicated
in effects of HIV-1 throughout the Full range of HIV-1-infected cells.