## Structure is a protein that ### Mitochondrial Fission. This page describes its structure, normal nervous system function, role in neurodegenerative disease, and potential as a therapeutic target.
MiD50 shares structural features with MiD49:
- N-terminal cytosolic domain: Contains protein interaction motifs for Drp1 binding
- Transmembrane anchor: Single helix that localizes the protein to mitochondria
- C-terminal region: Faces the intermembrane space
MiD50 can form homodimers and heterodimers with MiD49, allowing fine-tuned regulation of mitochondrial fission.
MiD50 functions as a molecular scaffold:
- Recruits Drp1 to prospective fission sites on mitochondria
- Facilitates the assembly of the Drp1 oligomeric ring
- Promotes mitochondrial membrane constriction
- Works together with MiD49 for optimal fission efficiency
MiD50 integrates fission with quality control:
- Links mitochondrial dynamics to mitophagy initiation
- Coordinates with PINK1/Parkin pathway
- Participates in mitochondrial stress responses
- Drp1: Primary effector for mitochondrial fission
- MiD49: Functional partner for fission regulation
- Miro1: Coordinates fission with mitochondrial transport
- MFN1/2: Balances fission with fusion
MiD50 dysfunction in PD:
- Impaired mitochondrial fission in dopaminergic neurons
- Disrupted mitophagy leading to accumulation of defective mitochondria
- Interaction with PINK1/Parkin mitophagy pathway
- Enhanced susceptibility to mitochondrial toxins
In AD, MiD50 contributes to:
- Amyloid-beta-induced mitochondrial fragmentation
- Tau pathology affecting mitochondrial dynamics
- Synaptic mitochondrial depletion
- Neuronal energy deficits
MiD50 dysfunction has been implicated in:
- ALS: Impaired mitochondrial quality control in motor neurons
- HD: Altered mitochondrial dynamics in striatal neurons
- FTD: Mitochondrial dysfunction in frontal and temporal cortices
| Approach |
Status |
Description |
| Small molecule modulators |
Research |
Modulating MiD50-Drp1 interaction |
| Peptide inhibitors |
Preclinical |
Blocking excessive fission signaling |
| Gene expression modulators |
Research |
Normalizing MiD50 levels |