The GTF2H2 Knockout HeLa Polyclonal Cells product provides a polyclonal population of HeLa cells subjected to CRISPR/Cas9-mediated disruption of the GTF2H2 gene. This loss-of-function model is designed for researchers investigating the dual roles of the TFIIH complex in transcription initiation by RNA polymerase II and nucleotide excision repair (NER). The polyclonal format captures a heterogeneous mixture of edited alleles, enabling the study of gene disruption effects across a population while avoiding clonal selection artifacts. The cells serve as a versatile tool for functional genomics, DNA repair studies, and cancer biology, particularly in contexts where the interplay between transcription and genomic maintenance is critical.
Derived from the HeLa cell line, an HPV18-positive cervical adenocarcinoma epithelial model, these knockout cells retain the well-characterized genomic and phenotypic features of the parental line. HeLa cells are widely adopted for studying human cell signaling, viral oncogenesis, and DNA damage responses, and their p53- and Rb-deficient background provides a sensitized environment for examining tumor-suppressor pathway interactions. The immortalized nature and robust growth characteristics of HeLa cells facilitate high-throughput screening and long-term experimental manipulations, making them an ideal host for investigating the consequences of GTF2H2 loss in a transformed cellular context.
The GTF2H2 gene encodes the p44 subunit of the TFIIH complex, which operates at the nexus of transcription and DNA repair. As part of the core TFIIH, p44 interacts with XPB, XPD, p62, p52, and p34, and is regulated by the CDK7?Ccyclin H?CMAT1 kinase module. Functionally, GTF2H2 facilitates promoter opening and phosphorylation of the RNA polymerase II C-terminal domain at Ser5, a critical step in transcription initiation. During NER, TFIIH unwinds DNA around lesions and coordinates the recruitment of downstream endonucleases including XPA, XPG, and XPF-ERCC1. Loss of GTF2H2 disrupts both transcriptional output and the repair of UV-induced and other helix-distorting lesions, providing a direct link to diseases such as xeroderma pigmentosum, trichothiodystrophy, and Cockayne syndrome.
In the HeLa background, GTF2H2 knockout is expected to compromise the cell??s ability to cope with genotoxic stress and maintain transcriptional programs, thereby unmasking vulnerabilities relevant to cancer susceptibility. The HPV18-positive status of HeLa cells introduces an additional layer of relevance, as viral oncoproteins E6 and E7 are known to interfere with p53 and Rb pathways, respectively, which can influence DNA repair dynamics. Consequently, this model is particularly valuable for dissecting how viral transformation modifies the cellular reliance on TFIIH-dependent NER and transcription, and for testing synthetic lethality paradigms that exploit DNA repair deficiencies in cancer cells.
Researchers can apply this polyclonal knockout model in a range of experimental workflows. Transcription regulation studies can leverage RNA-seq and ChIP-qPCR to assess changes in gene expression and RNA polymerase II occupancy. DNA repair functional assays, such as UV sensitivity and host cell reactivation assays, directly measure NER capacity. Immunofluorescence and western blotting enable monitoring of TFIIH complex assembly and downstream repair factor recruitment, while cellular viability screens can identify chemical sensitivities conferred by GTF2H2 loss. For additional details or technical support, please contact Ascent Research.
