The CCNT2 Knockout HEK293T Polyclonal Cells are a population of HEK293T cells with CRISPR/Cas9-mediated disruption of the CCNT2 gene, creating a loss-of-function model for Cyclin T2. This polyclonal pool contains diverse edited alleles, suitable for studies that do not require clonal isolation. It allows examination of CCNT2 ablation in a bulk population, avoiding clonal artifacts.
HEK293T cells, derived from human embryonic kidney cells, are immortalized with adenovirus 5 DNA and stably express SV40 large T-antigen, conferring high transfection efficiency and robust protein expression. This cell line is widely used for viral production, protein expression, and genetic manipulation, providing a reliable platform for investigating CCNT2 function.
CCNT2 encodes Cyclin T2, the regulatory subunit of P-TEFb. It binds CDK9 to form active P-TEFb, which phosphorylates RNA polymerase II CTD at Ser2 and elongation factors DSIF and NELF, releasing promoter-proximal pausing and enabling transcription elongation. P-TEFb is regulated by CDK7 phosphorylation, sequestration by HEXIM1/7SK snRNA, and recruitment by NF-??B and ??-catenin. In HIV-1, Tat binds Cyclin T2 and CDK9 to recruit P-TEFb to the viral LTR. Downstream targets include MYC, MCL1, and FOS, linking Cyclin T2 to oncogenic and immediate-early gene transcription.
Disrupting CCNT2 in HEK293T cells impairs P-TEFb-dependent phosphorylation and reduces expression of target genes. The HEK293T background allows reconstitution with exogenous Cyclin T2 variants for structure-function studies and co-transfection of HIV-1 Tat with LTR-reporter constructs to analyze viral transactivation. Additionally, the involvement of Cyclin T2 in NF-??B and Wnt/??-catenin pathways makes these cells useful for studying signal-induced transcription elongation crosstalk.
These knockout cells are suited for Western blotting of CCNT2, CDK9, and phospho-RNA Pol II; RT-qPCR of MYC, FOS, and MCL1; HIV-1 LTR-luciferase assays; ChIP-qPCR for Pol II occupancy; co-immunoprecipitation of CCNT2 with CDK9 or Tat; RNA-seq transcriptome profiling; and cell viability assays. For further information, please contact Ascent Research.
