PMID: 15183343 In the absence of the viral Tat protein, RNA polymerase II initiates transcription from the viral LTR, but is defective for elongation and few productive transcripts are made. PMID: 15183343, 11713532, 11713533 A small nuclear RNA known as 7SK snRNA has been found to associate with a significant portion of P-TEFb and negatively regulate kinase activity in vitro, leading to the proposal that 7SK snRNA is a negative regulator of P-TEFb function.

PMID: 15183343, 2654643 NF-¦ÊB is induced under viral infected conditions and contributes to an increase in LTR transcription and viral replication. PMID: 15183343, 11713532, 11713533 A small nuclear RNA known as 7SK snRNA has been found to associate with a significant portion of P-TEFb and negatively regulate kinase activity in vitro, leading to the proposal that 7SK snRNA is a negative regulator of P-TEFb function.

PMID: 15183343 PMA treatment of U937 and HL-60 cells produced an increase of cyclin T1 protein expression from very low levels

PMID: 15183343, 15254183 Using proteasome inhibitors, we have recently observed that the shut off of cyclin T1 in uninfected late-differentiated macrophages involves proteasome-mediated proteolysis.

PMID: 15183343, 12368300 We observed that treatment of macrophages with lipopolysaccharide (LPS) at late time points of differentiation re-induces cyclin T1 protein expression.

PMID: 15183343 HIV-infected macrophages secrete at least two chemokines, MIP1¦Á and MIP1¦Â, which recruit and activate resting CD4+ T lymphocytes.Analysis of viral genes involved in the secretion of these chemokines revealed that the HIV-1 Nef protein is responsible for the induction of chemokines.

PMID: 15183343 HIV-infected macrophages secrete at least two chemokines, MIP1¦Á and MIP1¦Â, which recruit and activate resting CD4+ T lymphocytes.Analysis of viral genes involved in the secretion of these chemokines revealed that the HIV-1 Nef protein is responsible for the induction of chemokines.

PMID: 15183343 CDK9 is also found in other complexes that contain regulatory subunits other than cyclin T1; these additional cyclin partners of CDK9 are cyclins T2a, T2b, and K.

PMID: 15183343 CDK9 is also found in other complexes that contain regulatory subunits other than cyclin T1; these additional cyclin partners of CDK9 are cyclins T2a, T2b, and K.

PMID: 15183343 CDK9 is also found in other complexes that contain regulatory subunits other than cyclin T1; these additional cyclin partners of CDK9 are cyclins T2a, T2b, and K.

PMID: 15183343 Tat binds to TAR RNA in a complex with a cellular protein kinase complex termed TAK/P-TEFb (Tat-associated kinase/positive transcriptional elongation factor b). TAK/P-TEFb is composed of cyclin T1 as a regulatory subunit and CDK9 as the catalytic subunit.

PMID: 15183343, 12368300 The transient increase of cyclin T1 expression is specific to macrophage differentiation, as monocytes induced to differentiate to dendritic cells by GM-CSF and IL-4 sustain cyclin T1 expression.

PMID: 15183343, 12368300 The transient increase of cyclin T1 expression is specific to macrophage differentiation, as monocytes induced to differentiate to dendritic cells by GM-CSF and IL-4 sustain cyclin T1 expression.

PMID: 15183343, 12368300 The transient increase of cyclin T1 expression is specific to macrophage differentiation, as monocytes induced to differentiate to dendritic cells by GM-CSF and IL-4 sustain cyclin T1 expression.

PMID: 15183343, 12368300 The transient increase of cyclin T1 expression is specific to macrophage differentiation, as monocytes induced to differentiate to dendritic cells by GM-CSF and IL-4 sustain cyclin T1 expression.

PMID: 15183343, 11145967, 10757782, 11713532, 11713533 Binding of Tat complexed with TAK/P-TEFb to TAR RNA is believed to activate transcriptional elongation through the phosphorylation of the carboxyl terminal domain of RNA polymerase II, the Spt5 subunit of a negative factor termed DSIF, and perhaps other substrates in the polymerase complex. A small nuclear RNA known as 7SK snRNA has been found to associate with a significant portion of P-TEFb and negatively regulate kinase activity in vitro, leading to the proposal that 7SK snRNA is a negative regulator of P-TEFb function. PMID: 15183343 Association of TAK/P-TEFb with 7SK snRNA and MAQ1 reduces CDK9 kinase activity in vitro.

PMID: 15183343 Tat makes direct protein-protein complex with cyclin T1 and can therefore only target the cyclin T1-containing P-TEFb complex. PMID: 15183343 TAK/P-TEFb is composed of cyclin T1 as a regulatory subunit and CDK9 as the catalytic subunit.

PMID: 15183343 phosphorylation overcomes the active of negative factors (DSIF, NELF) that repress elongation

PMID: 15183343, 11713532, 11713533 A small nuclear RNA known as 7SK snRNA has been found to associate with a significant portion of P-TEFb and negatively regulate kinase activity in vitro, leading to the proposal that 7SK snRNA is a negative regulator of P-TEFb function.

PMID: 15183343, 12832472 A recent study has identified an additional protein termed MAQ1 that is associated with the 7SK/P-TEFb complex, and this association is dependent upon active RNA polymerase II transcription.

PMID: 15183343, 11145967, 10757782, 11713532, 11713533 Binding of Tat complexed with TAK/P-TEFb to TAR RNA is believed to activate transcriptional elongation through the phosphorylation of the carboxyl terminal domain of RNA polymerase II, the Spt5 subunit of a negative factor termed DSIF, and perhaps other substrates in the polymerase complex. A small nuclear RNA known as 7SK snRNA has been found to associate with a significant portion of P-TEFb and negatively regulate kinase activity in vitro, leading to the proposal that 7SK snRNA is a negative regulator of P-TEFb function. PMID: 15183343 Association of TAK/P-TEFb with 7SK snRNA and MAQ1 reduces CDK9 kinase activity in vitro.

PMID: 15183343, 2654643 NF-¦ÊB is induced under viral infected conditions and contributes to an increase in LTR transcription and viral replication.