MPP1 (Membrane Palmitoylated Protein 1)
A key scaffold protein in the erythrocyte membrane skeleton and a member of the MAGUK family, involved in cell signaling and adhesion.
Gene Information Card
| Symbol | MPP1 |
|---|---|
| Full Name | Membrane Palmitoylated Protein 1 |
| Gene Type | Protein coding |
| Chromosomal Location | Xq28 |
| NCBI Gene ID | 4354 ncbi.nlm.nih.gov/gene/4354 |
| Ensembl ID | ENSG00000130830 |
| UniProt ID | Q00013 |
| OMIM ID | 305360 |
| HGNC ID | 7218 |
| Aliases | EMP55, PEMP, MRG1, DXS552E |
Description
MPP1 (Membrane Palmitoylated Protein 1) encodes a member of the membrane-associated guanylate kinase (MAGUK) family. The protein is a major component of the erythrocyte membrane skeleton, where it links the membrane to the spectrin-actin cytoskeleton. It contains PDZ, SH3, and guanylate kinase-like domains, and is involved in cell signaling, cell adhesion, and maintenance of cell shape. Mutations in MPP1 are associated with hereditary spherocytosis and other red cell disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Hereditary spherocytosis | Mutations in MPP1 disrupt the interaction between the erythrocyte membrane and cytoskeleton, leading to loss of membrane surface area and spherical red blood cells. | ClinVar, OMIM |
| Elliptocytosis | Altered membrane stability due to defective MPP1 protein contributes to elliptical red cell morphology. | OMIM |
| Cancer (various) | MPP1 expression changes have been observed in certain cancers, potentially affecting cell adhesion and signaling pathways. | COSMIC |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Whole blood | 12.5 | Medium |
| Spleen | 8.2 | Low |
| Bone marrow | 6.1 | Low |
| Brain | 1.3 | Not detected |
| Liver | 0.5 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| K562 (erythroleukemia) | 15.3 | High expression; relevant for erythroid lineage studies |
| HEK293 (embryonic kidney) | 0.8 | Low expression; not endogenous |
| HeLa (cervical cancer) | 1.2 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.149G>A (p.Arg50His) | Missense | <0.01% | Alters PDZ domain; associated with hereditary spherocytosis |
| c.286C>T (p.Arg96Trp) | Missense | <0.01% | Disrupts SH3 domain; reported in ClinVar |
| c.1A>G (p.Met1Val) | Start loss | <0.01% | Loss of translation initiation; likely pathogenic |
Mutation functional classification
Loss of Function (LOF)
Missense mutations in PDZ or SH3 domains reduce protein stability or binding to partners, leading to membrane skeleton defects.
Gain of Function (GOF)
Not reported for MPP1.
Dominant Negative (DN)
Some missense mutations may interfere with wild-type protein function in heterozygous state, though evidence is limited.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Erythrocyte membrane skeleton pathway (Reactome: R-HSA-5621480)
• Cell junction organization (Reactome: R-HSA-421270)
Protein Summary
MPP1 is a 55 kDa palmitoylated membrane protein belonging to the MAGUK family. It is primarily expressed in erythroid cells and localizes to the plasma membrane. The protein contains an N-terminal PDZ domain, an SH3 domain, and a C-terminal guanylate kinase-like domain. It binds to glycophorin C and other membrane proteins, anchoring the spectrin-actin cytoskeleton. Palmitoylation at cysteine residues facilitates membrane association. MPP1 is essential for red blood cell shape and deformability.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| MPP1 Knockout HEK293 Cell Line | EDJ-KQ3121 | Human | 4354 | Details Get a Quote |
| MPP1 Knockout A-549 Cell Line | EDJ-KQ24475 | Human | 4354 | Details Get a Quote |
| MPP1 Knockout HCT 116 Cell Line | EDJ-KQ24476 | Human | 4354 | Details Get a Quote |
| MPP1 Knockout HeLa Cell Line | EDJ-KQ24477 | Human | 4354 | Details Get a Quote |
