9MY3: Xenopus KCNQ1-CaM in GDN

Structure of Xenopus KCNQ1-CaM in GDN. Determined by electron microscopy at 3.46 Å resolution. Released 15 Oct 2025.

Method: Electron microscopy
Resolution: 3.46 Å
Organisms: Xenopus laevis, Homo sapiens
Chains: 8
Atoms: 15,004
Mol. weight: 316.91 kDa
Released: 15 Oct 2025

Explore 9MY3 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9MY3 contains 116 α-helices and 16 β-strands across 8 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chains A, C, E and G: 21 helices, 0 β-strands

Element	Residues	Length
α-helix	96-105	10
α-helix	110-134	25
α-helix	139-167	29
α-helix	168-170	3
α-helix	177-183	7
α-helix	187-204	18
α-helix	217-226	10
α-helix	227-230	4
α-helix	236-247	12
α-helix	249-274	26
α-helix	289-300	12
α-helix	313-326	14
α-helix	328-347	20
α-helix	348-350	3
α-helix	351-353	3
α-helix	354-357	4
α-helix	358-373	16
α-helix	380-383	4
α-helix	499-520	22
α-helix	524-525	2
α-helix	527-553	27

Chains B, D, F and H: 8 helices, 4 β-strands

Element	Residues	Length	Sheet
α-helix	13-20	8
β-strand	27-28	2	1
α-helix	30-39	10
α-helix	46-54	9
β-strand	64-65	2	1
α-helix	66-74	9
α-helix	80-91	12
β-strand	100-102	3	2
α-helix	103-112	10
α-helix	119-128	10
β-strand	136-138	3	2
α-helix	139-145	7

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Potassium voltage-gated channel subfamily KQT member 1	A, C, E, G	protein	545	Xenopus laevis	P70057 (AlphaFold model)
Calmodulin-1	B, D, F, H	protein	149	Homo sapiens	P0DP23 (AlphaFold model)

Sequence of entity 1 (A, C, E, G), FASTA

>9MY3_1 Potassium voltage-gated channel subfamily KQT member 1 (chains A, C, E, G)
MATDPPRPTINLDPRVSIYSGRRPLLSRTNIQGRVYNFLERPTGWKCFVYHFTVFLIVLI
CLIFSVLSTIQQYNNLATETLFWMEIVLVVFFGAEYVVRLWSAGCRSKYVGVWGRLRFAR
KPISVIDLIVVVASVIVLCVGSNGQVFATSAIRGIRFLQILRMLHVDRQGGTWRLLGSVV
FIHRQELITTLYIGFLGLIFSSYFVYLAEKDAIDSSGEYQFGSYADALWWGVVTVTTIGY
GDKVPQTWIGKTIASCFSVFAISFFALPAGILGSGFALKVQQKQRQKHFNRQIPAAASLI
QTAWRCYAAENPDSATWKIYIRKQSRNHHLMSPSPKPKKSAMVKKKKIRTERDEGSTDKM
LNIPHITYDHVADDRKNDGYSVESYENTVRKPFGFLDPSTGPFIRTSSFTDDLDMEGDTL
LTPITHISELKEHHRAAIKVIRRMQYFVAKKKFQQARKPYDVRDVIEQYSQGHLNLMVRI
KELQRRLDQSLGKPSLFLSVSDKVKDKGINTIGSRLNRVEDKVTQMDHKLNLITDMLHHL
LTNQQ

Sequence of entity 2 (B, D, F, H), FASTA

>9MY3_2 Calmodulin-1 (chains B, D, F, H)
MADQLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADG
NGTIDFPEFLTMMARKMKDTDSEEEIREAFRVFDKDGNGYISAAELRHVMTNLGEKLTDE
EVDEMIREADIDGDGQVNYEEFVQMMTAK

Primary citation

A physiologically-relevant intermediate state structure of a voltage-gated potassium channel. Kyriakis, E., Sastre, D., Eldstrom, J. et al. Nat Commun (2025) 16:8814-8814. DOI 10.1038/s41467-025-64060-3 · PubMed

Other PDB entries of the same protein (UniProt P70057 (AlphaFold model), which also has an AlphaFold model), best resolution first:

9MY4 3.53 Å, Structure of Xenopus KCNQ1(E150R/R221E)-CaM with the VSD in the intermediate state
5VMS 3.7 Å, CryoEM structure of Xenopus KCNQ1 channel
10NL 3.81 Å, Xenopus KCNQ1 in complex with UCL2077
7TCP 3.84 Å, Structure of Xenopus KCNQ1-CaM
7TCI 3.9 Å, Structure of Xenopus KCNQ1-CaM in complex with ML277
10NK 3.95 Å, Xenopus KCNQ1 Intermediate State (E1R/R2E) in complex with UCL2077

Browse structure collections

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