Calcium-activated potassium channel subunit alpha-1 (KCNMA1) is a 1236-residue protein from Homo sapiens. This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: Q12791.
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The mean pLDDT of this model is 76.0 (confident overall). pLDDT is AlphaFold's per-residue confidence score from 0 to 100. In MolViewer, choose the B-factor color scheme to color the model by pLDDT, because AlphaFold stores it in the B-factor column.
| pLDDT band | Meaning | Share of residues |
|---|---|---|
| Above 90 | Very high: backbone and side chains are usually accurate | 47% |
| 70 to 90 | Confident: backbone generally right | 25% |
| 50 to 70 | Low: treat with caution | 4% |
| Below 50 | Very low: often disordered regions | 24% |
What pLDDT means and how to read it
Potassium channel activated by both membrane depolarization or increase in cytosolic Ca(2+) that mediates export of K(+) (PubMed:14523450, PubMed:29330545, PubMed:31152168). It is also activated by the concentration of cytosolic Mg(2+). Its activation dampens the excitatory events that elevate the cytosolic Ca(2+) concentration and/or depolarize the cell membrane. It therefore contributes to repolarization of the membrane potential. Plays a key role in controlling excitability in a number of systems, such as regulation of the contraction of smooth muscle, the tuning of hair cells in the cochlea, regulation of transmitter release, and innate immunity. In smooth muscles, its activation by…
Homotetramer; which constitutes the calcium-activated potassium channel. Interacts with RAB11B (By similarity). Interacts with beta subunits KCNMB1, KCNMB2, KCNMB3 and KCNMB4. Interacts with gamma subunits LRRC26, LRRC38, LRRC52 and LRRC55. Beta and gamma subunits are accessory, and modulate its activity
Cell membrane
Compare the prediction with experimentally determined structures of the same protein:
| PDB ID | Method | Resolution | Chains and residues |
|---|---|---|---|
| 6V5A | X-ray | 2.0 Å | A=406-1179 |
| 8V60 | EM | 2.43 Å | A/B/C/D=66-1179 |
| 9CZM | EM | 2.57 Å | A/B/C/D=66-1179 |
| 8V64 | EM | 2.6 Å | A/B/C/D=66-1179 |
| 8GHF | EM | 2.7 Å | A/B/C/D=67-1179 |
| 8V63 | EM | 2.72 Å | A/B/C/D=66-1179 |
| 9JO3 | EM | 2.8 Å | A/B/C/D=66-1184 |
| 8VAZ | EM | 2.82 Å | A/B/C/D=66-1179 |
| 9CZO | EM | 2.87 Å | A/B/C/D=66-1179 |
| 9CZQ | EM | 2.88 Å | A/B/C/D=66-1179 |
| 9D18 | EM | 2.88 Å | A/B/C/D=66-1179 |
| 9D19 | EM | 2.88 Å | A/B/C/D=66-1179 |
| 9CZH | EM | 2.9 Å | A/B/C/D=66-1179 |
| 3MT5 | X-ray | 3.0 Å | A=406-1179 |
| 3NAF | X-ray | 3.1 Å | A=394-1236 |
| 7YO3 | EM | 3.1 Å | A=66-1179 |
| 8VAV | EM | 3.13 Å | A/B/C/D=66-1179 |
| 6V22 | EM | 3.2 Å | A/B/C/D=66-1179 |
| 7YO2 | EM | 3.3 Å | A/B/C/D=66-1179 |
| 8GHG | EM | 3.3 Å | A/B/C/D=67-1179 |
Showing 20 of 36 experimental structures (best resolution first).
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