PMID- 10964778
OWN - NLM
STAT- MEDLINE
DCOM- 20000925
LR  - 20211203
IS  - 0042-6822 (Print)
IS  - 0042-6822 (Linking)
VI  - 274
IP  - 2
DP  - 2000 Sep 1
TI  - An in vitro transcription system that recapitulates equine infectious anemia 
      virus tat-mediated inhibition of human immunodeficiency virus type 1 Tat activity 
      demonstrates a role for positive transcription elongation factor b and associated 
      proteins in the mechanism of Tat activation.
PG  - 356-66
AB  - Equine infectious anemia virus (EIAV) activates transcription via a Tat protein, 
      a TAR element, and the equine elongation factor positive transcription elongation 
      factor b (P-TEFb). In human cells, EIAV Tat (eTat) can inhibit the ability of 
      human immunodeficiency virus type 1 (HIV-1) Tat (hTat) to activate transcription 
      from the HIV-1 long terminal repeat, demonstrating that EIAV Tat can interact 
      nonproductively with human P-TEFb. To study the mechanism of EIAV Tat and HIV-1 
      Tat activation, we developed an in vitro elongation assay that recapitulates EIAV 
      Tat-mediated inhibition of HIV-1 Tat trans-activation. We found that eTat 
      specifically inhibits activation of elongation by HIV-1 Tat while having no 
      effect on basal transcription elongation. The competitive inhibition of hTat 
      activation was reversed by an activity present in HeLa cell nuclear extracts, 
      most likely a form of P-TEFb. Recombinant P-TEFb (cyclin T1 and CDK9) overcame 
      the inhibition of transcription by eTat but in a nonspecific manner. EIAV Tat 
      affinity chromatography was used to purify the activity present in nuclear 
      extract that was capable of reversing eTat inhibition. We characterized the 
      protein components of this activity, which include cyclin T1, CDK9, Tat-SF1, and 
      at least three unidentified proteins. These data suggest that additional factors 
      are involved in the mechanism of Tat activation.
CI  - Copyright 2000 Academic Press.
FAU - Sune, C
AU  - Sune C
AD  - Departments of Genetics, Duke University Medical Center, Durham, North Carolina 
      27710, USA. csn@duke.edu
FAU - Goldstrohm, A C
AU  - Goldstrohm AC
FAU - Peng, J
AU  - Peng J
FAU - Price, D H
AU  - Price DH
FAU - Garcia-Blanco, M A
AU  - Garcia-Blanco MA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Virology
JT  - Virology
JID - 0110674
RN  - 0 (CCNT1 protein, human)
RN  - 0 (Cell Extracts)
RN  - 0 (Cyclin T)
RN  - 0 (Cyclins)
RN  - 0 (Gene Products, tat)
RN  - 0 (HTATSF1 protein, human)
RN  - 0 (Nuclear Proteins)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Trans-Activators)
RN  - 0 (tat Gene Products, Human Immunodeficiency Virus)
RN  - EC 2.7.11.- (Positive Transcriptional Elongation Factor B)
RN  - EC 2.7.11.1 (Protein Serine-Threonine Kinases)
RN  - EC 2.7.11.22 (CDK9 protein, human)
RN  - EC 2.7.11.22 (Cyclin-Dependent Kinase 9)
RN  - EC 2.7.11.22 (Cyclin-Dependent Kinases)
SB  - IM
MH  - Binding, Competitive
MH  - Cell Extracts
MH  - Cell-Free System
MH  - Chromatography, Affinity
MH  - Cyclin T
MH  - Cyclin-Dependent Kinase 9
MH  - Cyclin-Dependent Kinases/isolation & purification/metabolism
MH  - Cyclins/isolation & purification/metabolism
MH  - *Gene Expression Regulation, Viral
MH  - Gene Products, tat/*antagonists & inhibitors/isolation & purification/*metabolism
MH  - HIV Long Terminal Repeat/genetics
MH  - HIV-1/*genetics
MH  - HeLa Cells
MH  - Hot Temperature
MH  - Humans
MH  - *Infectious Anemia Virus, Equine
MH  - Nuclear Proteins/isolation & purification/metabolism
MH  - Positive Transcriptional Elongation Factor B
MH  - Promoter Regions, Genetic/genetics
MH  - Protein Binding
MH  - Protein Denaturation
MH  - Protein Serine-Threonine Kinases/*metabolism
MH  - Recombinant Proteins/antagonists & inhibitors/isolation & purification/metabolism
MH  - Substrate Specificity
MH  - Templates, Genetic
MH  - Time Factors
MH  - Trans-Activators/isolation & purification/metabolism
MH  - Transcription, Genetic/genetics
MH  - Transcriptional Activation
MH  - tat Gene Products, Human Immunodeficiency Virus
EDAT- 2000/08/31 11:00
MHDA- 2000/09/30 11:01
CRDT- 2000/08/31 11:00
PHST- 2000/08/31 11:00 [pubmed]
PHST- 2000/09/30 11:01 [medline]
PHST- 2000/08/31 11:00 [entrez]
AID - S0042-6822(00)90480-X [pii]
AID - 10.1006/viro.2000.0480 [doi]
PST - ppublish
SO  - Virology. 2000 Sep 1;274(2):356-66. doi: 10.1006/viro.2000.0480.