Huntingtin Interacting Protein 1
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HIP1 Protein is a protein encoded by the HIP1 gene. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
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| Protein Name | Huntingtin Interacting Protein 1 |
|---|
| Gene | [HIP1](/genes/hip1) |
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| UniProt ID | [Q9Y4X5](https://www.uniprot.org/uniprot/Q9Y4X5) |
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| PDB Structures | [2Y8W](https://www.rcsb.org/structure/2Y8W) |
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| Molecular Weight | ~116 kDa |
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| Subcellular Localization | Cytoplasm, cytoskeleton |
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| Protein Family | Huntingtin-associated protein family |
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HIP1 is a multi-domain scaffold protein with distinct structural features:
- N-terminal ANTH domain: Membrane-binding domain that binds phosphoinositides
- ** coiled-coil domains**: Mediate homo- and heterodimerization
- CLATHRIN-binding domain: Links to clathrin-coated vesicle machinery
- Talin-like helical domain: Involved in actin binding
- C-terminal proline-rich region: Contains multiple SH3-binding motifs
The protein forms homodimers via its coiled-coil regions and interacts with huntingtin through its N-terminal region.
HIP1 functions as a versatile scaffold protein:
- Clathrin-mediated endocytosis: Links cargo to clathrin-coated vesicles
- Actin cytoskeleton: Connects membrane proteins to the actin cytoskeleton
- Synaptic function: Involved in synaptic vesicle trafficking
- Huntingtin interaction: Binds huntingtin, potentially modulating its function
- Cell division: Roles in cytokinesis and cell division
In neurons, HIP1 is implicated in maintaining synaptic architecture and function.
- Huntingtin interaction: HIP1 binds mutant huntingtin with altered affinity [1]
- Loss of function: Reduced HIP1 levels in HD patient brains
- Synaptic dysfunction: Contributes to synaptic vesicle trafficking defects
- Pathogenic mechanisms: May contribute to loss of normal huntingtin function
- Endocytic trafficking: Dysregulated endocytosis is an early AD feature
- Amyloid processing: HIP1 may influence APP trafficking and processing
- Synaptic vulnerability: Contributes to synaptic dysfunction
- Endocytic pathways: Altered endocytic function in PD models
- Alpha-synuclein interactions: Potential involvement in synucleinopathy
- Oncogenic roles: HIP1 has been implicated in various cancers
- Androgen receptor: Linked to prostate cancer progression
- Protein-protein interaction modulators: Targeting huntingtin-HIP1 interaction
- Endocytic pathway modulators: Restoring normal trafficking function
- Biomarkers: HIP1 levels as potential disease markers
- Mechanism studies: Understanding HIP1's role in neurodegeneration
| Interactor |
Function |
Reference |
| Huntingtin |
Mutant huntingtin interaction |
1 |
| Clathrin |
Clathrin-mediated endocytosis |
2 |
| Actin |
Cytoskeletal binding |
3 |
| AP2 |
Clathrin adaptor complex |
4 |