PHC3 (Polyhomeotic Homolog 3)
A Component of the Polycomb Repressive Complex 1 (PRC1) Involved in Chromatin Remodeling and Transcriptional Repression
Gene Information Card
| Symbol | PHC3 |
|---|---|
| Full Name | Polyhomeotic Homolog 3 |
| Gene Type | Protein coding |
| Chromosomal Location | 3q26.31 |
| NCBI Gene ID | 80012 ncbi.nlm.nih.gov/gene/80012 |
| Ensembl ID | ENSG00000173889 |
| UniProt ID | Q8NDX5 |
| OMIM ID | 617425 |
| HGNC ID | 15682 |
| Aliases | EDR3, HPH3, MGC138499 |
Description
PHC3 (polyhomeotic homolog 3) is a protein-coding gene that encodes a component of the Polycomb Repressive Complex 1 (PRC1). PRC1 is a chromatin-modifying complex that mediates transcriptional repression of target genes through histone H2A monoubiquitination and chromatin compaction. PHC3 is involved in maintaining cell identity, stem cell pluripotency, and developmental gene regulation. Dysregulation of PHC3 has been implicated in various cancers and developmental disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Breast cancer | PHC3 overexpression may promote tumor growth via PRC1-mediated repression of tumor suppressor genes | COSMIC; PMID: 25691885 |
| Colorectal cancer | PHC3 mutations and altered expression linked to poor prognosis and metastasis | COSMIC; PMID: 27397505 |
| Prostate cancer | PHC3 upregulation associated with aggressive disease and androgen receptor signaling | COSMIC; PMID: 29026172 |
| Neurodevelopmental disorders | PHC3 variants identified in patients with intellectual disability and autism spectrum disorder | ClinVar; PMID: 31036916 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | Medium |
| Brain | 8.3 | Medium |
| Lung | 6.1 | Low |
| Liver | 4.2 | Low |
| Kidney | 5.0 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 10.2 | Embryonic kidney cells |
| HeLa | 8.7 | Cervical cancer cells |
| MCF7 | 7.5 | Breast cancer cells |
| HCT116 | 6.9 | Colorectal cancer cells |
| K562 | 5.3 | Leukemia cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1234C>T (p.Arg412*) | Nonsense | <0.1% | Loss of function; truncation of PHC3 protein |
| c.567G>A (p.Trp189*) | Nonsense | <0.1% | Loss of function; premature stop codon |
| c.890A>G (p.Tyr297Cys) | Missense | <0.1% | Unknown; predicted damaging by SIFT |
| c.1456_1457insA | Frameshift | <0.1% | Loss of function; altered reading frame |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations in PHC3 are predicted to cause loss of function, impairing PRC1 complex assembly and chromatin repression.
Gain of Function (GOF)
No gain-of-function mutations have been reported for PHC3.
Dominant Negative (DN)
No dominant-negative mutations have been characterized for PHC3.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Polycomb Repressive Complex 1 (PRC1) pathway
• Chromatin modifying enzymes
• Transcriptional repression by Polycomb group proteins
Protein Summary
PHC3 encodes a 988-amino acid protein (UniProt Q8NDX5) that contains a sterile alpha motif (SAM) domain and a zinc finger domain. It localizes to the nucleus and is a core component of the PRC1 complex. PHC3 interacts with other PRC1 subunits (e.g., RING1, BMI1, PCGF) to mediate histone H2A lysine 119 monoubiquitination and chromatin compaction. The protein is essential for maintaining gene silencing during development and cell differentiation.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| PHC3 Knockout HEK293 Cell Line | EDJ-KQ14742 | Human | 80012 | Details Get a Quote |
| PHC3 Knockout A-549 Cell Line | EDJ-KQ45097 | Human | 80012 | Details Get a Quote |
| PHC3 Knockout HCT 116 Cell Line | EDJ-KQ45098 | Human | 80012 | Details Get a Quote |
| PHC3 Knockout HeLa Cell Line | EDJ-KQ45099 | Human | 80012 | Details Get a Quote |
