MAF1: A Key Repressor of RNA Polymerase III Transcription
Regulator of tRNA and 5S rRNA synthesis, implicated in cancer and metabolic disorders
Gene Information Card
| Symbol | MAF1 |
|---|---|
| Full Name | MAF1 homolog, negative regulator of RNA polymerase III |
| Gene Type | Protein coding |
| Chromosomal Location | 8q24.3 |
| NCBI Gene ID | 84232 ncbi.nlm.nih.gov/gene/84232 |
| Ensembl ID | ENSG00000179632 |
| UniProt ID | Q9H063 |
| OMIM ID | 610210 |
| HGNC ID | 24966 |
| Aliases | MAF1, Maf1 regulator, RNA polymerase III repressor |
Description
MAF1 is a highly conserved negative regulator of RNA polymerase III transcription. It represses the synthesis of small non-coding RNAs such as tRNAs and 5S rRNA in response to nutrient deprivation, stress, and growth signals. MAF1 functions by binding to the RNA polymerase III complex and inhibiting its activity. Dysregulation of MAF1 is associated with cancer, metabolic disorders, and altered cell growth.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cancer (various types) | Loss of MAF1 leads to increased RNA Pol III transcription, promoting cell proliferation and tumorigenesis | PMID: 23431136, COSMIC |
| Metabolic syndrome | MAF1 regulates lipid metabolism and insulin sensitivity; altered expression linked to metabolic dysfunction | PMID: 25936801 |
| Hepatocellular carcinoma | Reduced MAF1 expression correlates with poor prognosis and increased tRNA synthesis | PMID: 27325790 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 12.5 | Medium |
| Brain | 8.3 | Low |
| Heart | 10.1 | Medium |
| Kidney | 14.2 | Medium |
| Testis | 18.7 | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 15.3 | Embryonic kidney cells |
| HeLa | 12.8 | Cervical cancer cells |
| HepG2 | 11.4 | Hepatocellular carcinoma cells |
| A549 | 9.7 | Lung cancer cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | Rare | Likely loss of function; reduced protein expression |
| c.214C>T (p.Arg72Trp) | Missense | 0.01% | Unknown significance; may affect repressor activity |
| c.487_489del (p.Lys163del) | In-frame deletion | Rare | Alters protein stability and function |
Mutation functional classification
Loss of Function (LOF)
Most MAF1 mutations are predicted to reduce repressor activity, leading to increased RNA Pol III transcription and uncontrolled cell growth.
Gain of Function (GOF)
No gain-of-function mutations have been reported in MAF1.
Dominant Negative (DN)
No dominant-negative mutations have been described for MAF1.
View complete mutation data：
Gene Ontology (GO)
| • negative regulation of transcription by RNA polymerase III (GO:0000122) | • nucleus (GO:0005634) |
| • protein binding (GO:0005515) | • RNA polymerase III activity (GO:0001056) |
| • transcription of nuclear large rRNA transcript from RNA polymerase I promoter (GO:0042790) |
Pathways
• RNA polymerase III transcription
• mTOR signaling pathway
• p53 signaling pathway
• Metabolic signaling
Protein Summary
MAF1 is a 256-amino acid protein that acts as a master repressor of RNA polymerase III. It is regulated by phosphorylation via mTOR and other kinases. Upon dephosphorylation, MAF1 translocates to the nucleus and binds to the RNA Pol III complex, inhibiting transcription of tRNAs and 5S rRNA. This regulation is critical for cellular homeostasis, stress response, and growth control.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| MAF1 Knockout HEK293 Cell Line | EDJ-KQ3083 | Human | 84232 | Details Get a Quote |
| MAF1 Knockout A-549 Cell Line | EDJ-KQ24384 | Human | 84232 | Details Get a Quote |
| MAF1 Knockout HCT 116 Cell Line | EDJ-KQ24385 | Human | 84232 | Details Get a Quote |
| MAF1 Knockout HeLa Cell Line | EDJ-KQ24386 | Human | 84232 | Details Get a Quote |
