| CACNA1F Protein |
|---|
| Protein Name | Voltage-dependent L-type calcium channel subunit alpha-1F |
| Gene | [CACNA1F](/genes/cacna1f) |
| Category | Protein |
| Path | /proteins/cacna1f-protein |
| UniProt ID | O43497 |
| Protein Family | Voltage-gated calcium channel (Cav1.2) |
CACNA1F encodes the alpha-1F subunit of voltage-gated L-type calcium channels, also known as Cav1.4. This protein forms the pore-forming core of the calcium channel complex and is essential for calcium influx in response to membrane depolarization. The CACNA1F protein contains 2,166 amino acids and represents the primary calcium-conducting component of Cav1.4 channels, which are critically important for synaptic transmission and retinal signaling.
CACNA1F forms L-type voltage-gated calcium channels (Cav1.4) that mediate:
- Calcium influx: Permits selective Ca²⁺ entry upon membrane depolarization
- Excitation-contraction coupling: Initiates muscle contraction through calcium-induced calcium release
- Excitation-transcription coupling: Activates calcium-dependent gene expression
- Neurotransmitter release: Triggers synaptic vesicle fusion at presynaptic terminals
CACNA1F exhibits distinctive expression patterns:
The highest expression is in retinal photoreceptors:
- Rod bipolar cells: Essential for scotopic (low-light) vision
- Cone pathways: Contributes to photopic (bright-light) vision
- Horizontal cells: Modulates synaptic processing in the outer retina
Lower expression in:
- Cardiac muscle (minor expression)
- Skeletal muscle (minor expression)
- Endocrine tissues
CACNA1F mutations are primarily associated with visual disorders:
- Congenital stationary night blindness (CSNB): Multiple CACNA1F mutations cause this non-progressive retinal disorder
- Retinitis pigmentosa: Some mutations lead to progressive photoreceptor degeneration
- Electroretinogram abnormalities: Characteristic b-wave reductions
Although primarily retinal, CACNA1F dysregulation may affect:
- Epilepsy: Altered calcium channel function in neuronal excitability
- Neurodevelopmental disorders: Possible roles in synapse formation
- Migraine: Cortical calcium signaling involvement
Minor cardiac expression suggests potential roles in:
- Cardiac development
- Pacemaker activity
CACNA1F assembles with auxiliary subunits to form functional channels:
Cav1.4 (alpha-1F) + Beta2/Beta4 + Alpha2-Delta4
The alpha-1F subunit contains:
- 24 transmembrane segments (4 repeats)
- Voltage sensors in segments IVS1-4
- DHP-sensitive pore region
- C-terminal calmodulin binding domain
- Slow inactivation: Unlike other Cav1 channels, Cav1.4 shows minimal inactivation
- Low-voltage activation: Activates at relatively negative voltages
- Sustained currents: Supports prolonged calcium influx
CACNA1F interacts with:
CACNA1F interacts with:
Cav1.4 channels represent potential targets for:
- Retinal therapeutics: Modulating photoreceptor calcium channels
- Neuroprotective agents: Ca²⁺ channel blockers for retinal diseases
- Epilepsy treatments: CNS-targeted L-type channel modulators
- Developing retinal-selective calcium channel modulators
- Understanding genotype-phenotype relationships in CSNB
- Gene therapy approaches for CACNA1F mutations
- Striessnig et al., L-type Ca2+ channels (2014)
- Koschak et al., Cav1.4 alpha1F subunits (2003)
- McRory et al., CACNA1F mutations cause CSNB (2004)
- Pedrotti et al., Cav1.4 channel physiology (2021)