CTDP1: RNA Polymerase II Subunit A C-Terminal Domain Phosphatase
Key regulator of transcription and DNA repair, implicated in congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) and Charcot-Marie-Tooth disease.
Gene Information Card
| Symbol | CTDP1 |
|---|---|
| Full Name | CTD (carboxy-terminal domain) phosphatase 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 18q23 |
| NCBI Gene ID | 9150 ncbi.nlm.nih.gov/gene/9150 |
| Ensembl ID | ENSG00000101412 |
| UniProt ID | Q9Y5B0 |
| OMIM ID | 604927 |
| HGNC ID | 2498 |
| Aliases | FCP1 |
Description
CTDP1 encodes the RNA polymerase II subunit A C-terminal domain phosphatase, also known as FCP1. This enzyme dephosphorylates the C-terminal domain (CTD) of RNA polymerase II, a critical step in transcription elongation and termination. CTDP1 also participates in DNA repair pathways. Mutations in CTDP1 cause congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) and are associated with Charcot-Marie-Tooth disease.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) | Loss-of-function mutations impair CTD dephosphorylation, disrupting transcription and leading to developmental and neurological defects. | ClinVar, OMIM |
| Charcot-Marie-Tooth disease (CMT) | Specific missense variants (e.g., p.Arg259His) reduce phosphatase activity, causing peripheral neuropathy. | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | Medium |
| Brain | 8.2 | Medium |
| Heart | 6.1 | Low |
| Liver | 4.3 | Low |
| Kidney | 5.0 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 10.1 | Cervical cancer cell line |
| HEK293 | 8.7 | Embryonic kidney cells |
| K562 | 7.3 | Leukemia cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.156_157delAG | Frameshift | Rare (founder in Roma) | Loss of function; causes CCFDN |
| c.776G>A (p.Arg259His) | Missense | Rare | Reduced phosphatase activity; associated with CMT |
| c.1240C>T (p.Arg414*) | Nonsense | Rare | Premature stop; loss of function |
Mutation functional classification
Loss of Function (LOF)
Frameshift and nonsense mutations (e.g., c.156_157delAG, p.Arg414*) lead to truncated or absent protein, causing CCFDN.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
Missense variants like p.Arg259His may exert a dominant-negative effect by interfering with wild-type CTDP1 function in heterozygous state.
View complete mutation data：
Gene Ontology (GO)
Pathways
• RNA polymerase II transcription (Reactome R-HSA-75955)
• DNA repair (Reactome R-HSA-73894)
Protein Summary
CTDP1 (FCP1) is a 961-amino acid protein with a C-terminal phosphatase domain that specifically dephosphorylates Ser2 and Ser5 of the RNA polymerase II CTD heptad repeat. It is essential for transcription cycle progression and is recruited by TFIIF. The protein also interacts with BRCA1, linking it to DNA damage response.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| No Data | ||||
