7XNN: Human KCNQ1-CaM-ML277-PIP2 complex in state B

human KCNQ1-CaM-ML277-PIP2 complex in state B. Determined by electron microscopy at 2.5 Å resolution. Released 14 Dec 2022.

Method: Electron microscopy
Resolution: 2.5 Å
Organism: Homo sapiens
Chains: 8
Atoms: 14,280
Mol. weight: 389.44 kDa
Ligands: I0S, PIO
Released: 14 Dec 2022

Explore 7XNN in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

7XNN contains 104 α-helices and 0 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, D, F and H: 9 helices, 0 β-strands

Element	Residues	Length
α-helix	12-17	6
α-helix	18-20	3
α-helix	30-40	11
α-helix	46-54	9
α-helix	80-82	3
α-helix	85-92	8
α-helix	103-110	8
α-helix	119-127	9
α-helix	139-146	8

Chains B, C, E and G: 17 helices, 0 β-strands

Element	Residues	Length
α-helix	106-114	9
α-helix	121-141	21
α-helix	146-148	3
α-helix	151-176	26
α-helix	182-184	3
α-helix	186-194	9
α-helix	197-211	15
α-helix	212-216	5
α-helix	224-236	13
α-helix	237-240	4
α-helix	246-284	39
α-helix	299-310	12
α-helix	323-335	13
α-helix	337-340	4
α-helix	342-382	41
α-helix	507-531	25
α-helix	538-554	17

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Calmodulin-3	A, D, F, H	protein	177	Homo sapiens	P0DP25 (AlphaFold model)
Potassium voltage-gated channel subfamily KQT member 1	B, C, E, G	protein	692	Homo sapiens	P51787 (AlphaFold model)

Sequence of entity 1 (A, D, F, H), FASTA

>7XNN_1 Calmodulin-3 (chains A, D, F, H)
MADQLTEEQIAEFKEAFSLFDKDGDGTITTKELGTVMRSLGQNPTEAELQDMINEVDADG
NGTIDFPEFLTMMARKMKDTDSEEEIREAFRVFDKDGNGYISAAELRHVMTNLGEKLTDE
EVDEMIREADIDGDGQVNYEEFVQMMTAKLEGGSSGGLVPRGSGGSSGGHHHHHHHH

Sequence of entity 2 (B, C, E, G), FASTA

>7XNN_2 Potassium voltage-gated channel subfamily KQT member 1 (chains B, C, E, G)
MAAASSPPRAERKRWGWGRLPGARRGSAGLAKKCPFSLELAEGGPAGGALYAPIAPGAPG
PAPPASPAAPAAPPVASDLGPRPPVSLDPRVSIYSTRRPVLARTHVQGRVYNFLERPTGW
KCFVYHFAVFLIVLVCLIFSVLSTIEQYAALATGTLFWMEIVLVVFFGTEYVVRLWSAGC
RSKYVGLWGRLRFARKPISIIDLIVVVASMVVLCVGSKGQVFATSAIRGIRFLQILRMLH
VDRQGGTWRLLGSVVFIHRQELITTLYIGFLGLIFSSYFVYLAEKDAVNESGRVEFGSYA
DALWWGVVTVTTIGYGDKVPQTWVGKTIASCFSVFAISFFALPAGILGSGFALKVQQKQR
QKHFNRQIPAAASLIQTAWRCYAAENPDSSTWKIYIRKAPRSHTLLSPSPKPKKSVVVKK
KKFKLDKDNGVTPGEKMLTVPHITCDPPEERRLDHFSVDGYDSSVRKSPTLLEVSMPHFM
RTNSFAEDLDLEGETLLTPITHISQLREHHRATIKVIRRMQYFVAKKKFQQARKPYDVRD
VIEQYSQGHLNLMVRIKELQRRLDQSIGKPSLFISVSEKSKDRGSNTIGARLNRVEDKVT
QLDQRLALITDMLHQLLSLHGGSTPGSGGPPREGGAHITQPCGSGGSVDPELFLPSNTLP
TYEQLTVPRRGPDEGSLEGGSSGGWSHPQFEK

Ligands and cofactors

ID	Name	Formula	Copies
I0S	(2R)-N-[4-(4-methoxyphenyl)-1,3-thiazol-2-yl]-1-(4-methylbenzene-1-sulfonyl)pip…	C23 H25 N3 O4 S2	4
PIO	[(2R)-2-octanoyloxy-3-[oxidanyl-[(1R,2R,3S,4R,5R,6S)-2,3,6-tris(oxidanyl)-4,5-d…	C25 H49 O19 P3	4

Water and common crystallization additives (K) are not listed.

Primary citation

Structural mechanisms for the activation of human cardiac KCNQ1 channel by electro-mechanical coupling enhancers. Ma, D., Zhong, L., Yan, Z. et al. Proc Natl Acad Sci U S A (2022) 119:e2207067119-e2207067119. DOI 10.1073/pnas.2207067119 · PubMed

Other PDB entries of the same protein (UniProt P0DP25 (AlphaFold model), which also has an AlphaFold model), best resolution first:

6K67 1.95 Å, Application of anti-helix antibodies in protein structure determination (9011-3LRH)
7BYL 2.5 Å, Cryo-EM structure of human KCNQ4
7XNK 2.6 Å, human KCNQ1-CaM in complex with ML277
7VNP 2.79 Å, Structure of human KCNQ4-ML213 complex with PIP2
7VNR 2.8 Å, Structure of human KCNQ4-ML213 complex in digitonin
9LJ5 2.9 Å, Human KCNQ5-CaM-PIP2-HN37 complex in an open conformation.
7VNQ 2.96 Å, Structure of human KCNQ4-ML213 complex in nanodisc
7BYM 3.1 Å, Cryo-EM structure of human KCNQ4 with retigabine
7XNL 3.1 Å, human KCNQ1-CaM-ML277-PIP2 complex in state A
9IXY 3.1 Å, Human KCNQ2-CaM-Ebio2 Complex in the Presence of PIP2
9LIZ 3.1 Å, Human KCNQ5-CaM in complex with PIP2
9LJ1 3.2 Å, Human KCNQ5-CaM-PIP2-HN37 complex in a closed conformation.

Browse structure collections

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