IMPDH2 Gene: Inosine Monophosphate Dehydrogenase 2
Key enzyme in guanine nucleotide biosynthesis, associated with immunodeficiency and cancer
Gene Information Card
| Symbol | IMPDH2 |
|---|---|
| Full Name | Inosine Monophosphate Dehydrogenase 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 3p21.31 |
| NCBI Gene ID | 3615 ncbi.nlm.nih.gov/gene/3615 |
| Ensembl ID | ENSG00000178035 |
| UniProt ID | P12268 |
| OMIM ID | 146830 |
| HGNC ID | 6053 |
| Aliases | IMPD2, IMPD, IMPDH-II |
Description
IMPDH2 encodes inosine monophosphate dehydrogenase 2, a rate-limiting enzyme in the de novo synthesis of guanine nucleotides. It catalyzes the conversion of inosine monophosphate (IMP) to xanthosine monophosphate (XMP), which is essential for DNA and RNA synthesis. The enzyme is a tetramer and is critical for cell proliferation. Mutations in IMPDH2 are associated with combined immunodeficiency and have been implicated in certain cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Combined immunodeficiency due to IMPDH2 deficiency | Loss-of-function mutations impair guanine nucleotide synthesis, leading to defective T- and B-cell proliferation | ClinVar, OMIM |
| Retinitis pigmentosa | Potential role in retinal cell survival via nucleotide metabolism disruption | OMIM |
| Cancer (various types) | Gain-of-function or overexpression promotes cell proliferation and tumor growth | COSMIC, NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Lymph node | 25.6 | High |
| Spleen | 22.3 | High |
| Bone marrow | 18.9 | High |
| Lung | 10.2 | Medium |
| Liver | 8.5 | Medium |
| Brain | 3.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 20.1 | Embryonic kidney cells |
| HeLa | 18.5 | Cervical cancer cells |
| K562 | 22.0 | Leukemia cells |
| HepG2 | 15.3 | Liver cancer cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.458C>T (p.Thr153Ile) | Missense | Rare | Loss of function; associated with immunodeficiency |
| c.787G>A (p.Gly263Arg) | Missense | Rare | Loss of function; reduced enzyme activity |
| c.1090G>A (p.Gly364Ser) | Missense | Rare | Gain of function; linked to cancer |
| c.1360C>T (p.Arg454Trp) | Missense | Rare | Unknown effect; reported in COSMIC |
Mutation functional classification
Loss of Function (LOF)
Mutations such as p.Thr153Ile and p.Gly263Arg reduce enzyme activity, impairing guanine nucleotide synthesis and leading to immunodeficiency.
Gain of Function (GOF)
Mutations like p.Gly364Ser increase enzyme activity, promoting cell proliferation and tumorigenesis.
Dominant Negative (DN)
No dominant-negative mutations have been reported for IMPDH2.
View complete mutation data：
Gene Ontology (GO)
| • IMP dehydrogenase activity (GO:0003938) | • GMP biosynthetic process (GO:0006177) |
| • GTP binding (GO:0005525) | • cytoplasm (GO:0005737) |
| • cytosol (GO:0005829) |
Pathways
• Purine metabolism (KEGG: hsa00230)
• Guanine nucleotide biosynthesis (Reactome: R-HSA-73817)
Protein Summary
IMPDH2 is a 514-amino acid protein that forms a homotetramer. Each subunit contains a catalytic domain and a CBS (cystathionine beta-synthase) domain that regulates activity via ATP binding. The enzyme is a target for immunosuppressive drugs like mycophenolic acid. Its expression is high in proliferating cells, and dysregulation contributes to immune disorders and cancer.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| IMPDH2 Knockout HEK293 Cell Line | EDJ-KQ50392 | Human | 3615 | Details Get a Quote |
| IMPDH2 Knockout HeLa Cell Line | EDJ-KQ53656 | Human | 3615 | Details Get a Quote |
| IMPDH2 Knockout A-549 Cell Line | EDJ-KQ62130 | Human | 3615 | Details Get a Quote |
| IMPDH2 Knockout HCT 116 Cell Line | EDJ-KQ70620 | Human | 3615 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
