ASCC3 (Activating Signal Cointegrator 1 Complex Subunit 3) is a protein‑coding gene in the human genome. The gene encodes a component of the ASC‑1 transcriptional co‑activator complex, which participates in the regulation of gene expression and the cellular response to DNA damage.
Gene and protein
- Official symbol: ASCC3
- Full name: Activating Signal Cointegrator 1 Complex Subunit 3
- Chromosomal location: 6p21.31 (according to the GRCh38 reference assembly)
- Protein size: Approximately 3,200 amino acids; the protein belongs to the Ski2‑like RNA helicase family and contains conserved helicase domains (DEAD/DEAH box motifs).
Biological function
- ASCC3 functions as an ATP‑dependent helicase within the ASCC complex, facilitating the remodeling of nucleic acid–protein structures.
- The ASCC complex, comprising ASCC1, ASCC2, ASCC3 and the scaffold protein ASC‑1, is recruited to sites of alkylated DNA lesions where it promotes repair through transcription‑coupled nucleotide excision repair (TC‑NER).
- In addition to DNA repair, ASCC3 contributes to transcriptional activation by interacting with transcription factors and co‑activators, thereby influencing the expression of genes involved in cell growth and stress responses.
Expression
- ASCC3 mRNA is expressed broadly across human tissues, with higher levels observed in proliferative cell types such as embryonic stem cells and certain cancer cell lines.
Clinical relevance
- Alterations in ASCC3 expression or function have been associated with sensitivity to alkylating chemotherapeutic agents, reflecting its role in DNA damage resolution.
- Somatic mutations or dysregulation of ASCC3 have been reported in a subset of cancers, although the causal relationship remains under investigation.
Interactions
- ASCC3 interacts directly with ASCC1 and ASCC2 to form the functional ASCC complex.
- Protein‑protein interaction studies also indicate associations with components of the transcription machinery (e.g., RNA polymerase II) and DNA repair factors such as RAD23B.
Research tools
- Antibodies targeting ASCC3 are commercially available for immunoblotting and immunofluorescence.
- CRISPR/Cas9 gene‑editing and RNAi approaches have been employed to dissect ASCC3 function in cellular models.
References
- Peer‑reviewed articles describing the identification of ASCC3 as a Ski2‑like helicase and its involvement in transcription‑coupled DNA repair.
- Gene annotation databases (e.g., NCBI Gene, Ensembl) providing genomic coordinates, protein domains, and expression data.
Note: The information above reflects current knowledge compiled from established scientific literature and genome databases.
