7ZDZ: Human inward-rectifier potassium 2.1 channel

Cryo-EM structure of the human inward-rectifier potassium 2.1 channel (Kir2.1). Determined by electron microscopy at 4.3 Å resolution. Released 28 Sept 2022.

Method: Electron microscopy
Resolution: 4.3 Å
Organism: Homo sapiens
Chains: 4
Atoms: 10,369
Mol. weight: 193.59 kDa
Ligands: SR
Released: 28 Sept 2022

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

Secondary structure: helices and β-sheets

7ZDZ contains 30 α-helices and 68 β-strands across 4 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.

Chain A: 9 helices, 18 β-strands

Element	Residues	Length	Sheet
α-helix	56-58	3
α-helix	73-78	6
α-helix	84-109	26
α-helix	129-140	12
α-helix	155-184	30
β-strand	193-194	2	1
β-strand	199-204	6	2
β-strand	207-211	5	2
β-strand	212-213	2	3
β-strand	215-216	2	1
β-strand	222-223	2	4
β-strand	228-236	9	5
β-strand	242-249	8	5
β-strand	268-269	2	3
α-helix	284-289	6
β-strand	293-297	5	5
β-strand	300-302	3	4
β-strand	308-309	2	4
β-strand	312-313	2	5
β-strand	320-322	3	2
β-strand	325	1	6
α-helix	331	1
β-strand	332	1	7
α-helix	333	1
β-strand	337	1	7
β-strand	348	1	6
α-helix	358-365	8

Chain B: 7 helices, 18 β-strands

Element	Residues	Length	Sheet
β-strand	57-58	2	8
α-helix	61-63	3
α-helix	73-79	7
α-helix	84-114	31
α-helix	128-140	13
α-helix	155-184	30
β-strand	194	1	9
β-strand	202-204	3	10
β-strand	207-212	6	10
β-strand	215	1	9
β-strand	222-223	2	11
β-strand	228-236	9	12
β-strand	242-249	8	12
β-strand	269-272	4	10
α-helix	284-289	6
β-strand	293-297	5	12
β-strand	300-302	3	11
β-strand	308-309	2	11
β-strand	312	1	12
β-strand	315-316	2	12
β-strand	324-325	2	13
β-strand	330-333	4	14
β-strand	336-339	4	14
α-helix	341-343	3
β-strand	348-349	2	13

Chain C: 8 helices, 12 β-strands

Element	Residues	Length	Sheet
α-helix	74-78	5
α-helix	84-110	27
α-helix	129-140	12
α-helix	155-180	26
α-helix	181-183	3
β-strand	194-195	2	15
β-strand	200-204	5	16
β-strand	207-213	7	16
β-strand	214-215	2	15
β-strand	222-236	15	17
β-strand	242-249	8	17
β-strand	268-271	4	16
α-helix	284-288	5
β-strand	293-302	10	17
β-strand	308-315	8	17
β-strand	325-326	2	18
α-helix	327-328	2
β-strand	338-339	2	8
α-helix	341-343	3
β-strand	347-348	2	18

Chain D: 6 helices, 20 β-strands

Element	Residues	Length	Sheet
α-helix	71-109	39
α-helix	112-114	3
α-helix	130-140	11
α-helix	155-183	29
β-strand	193-195	3	19
β-strand	199	1	20
β-strand	200-204	5	21
β-strand	207-211	5	21
β-strand	212-213	2	22
β-strand	214-216	3	19
β-strand	223	1	23
β-strand	228-236	9	24
β-strand	242-249	8	24
β-strand	268-269	2	22
β-strand	272	1	21
α-helix	284-289	6
β-strand	293-297	5	24
β-strand	300-301	2	23
β-strand	308-309	2	23
β-strand	312-315	4	24
β-strand	320	1	20
β-strand	324-325	2	25
β-strand	332	1	26
β-strand	337	1	26
β-strand	348-349	2	25
α-helix	358-363	6

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Inward rectifier potassium channel 2	A, B, C, D	protein	427	Homo sapiens	P63252 (AlphaFold model)

Sequence of entity 1 (A, B, C, D), FASTA

>7ZDZ_1 Inward rectifier potassium channel 2 (chains A, B, C, D)
MGSVRTNRYSIVSSEEDGMKLATMAVANGFGNGKSKVHTRQQCRSRFVKKDGHCNVQFIN
VGEKGQRYLADIFTTCVDIRWRWMLVIFCLAFVLSWLFFGCVFWLIALLHGDLDASKEGK
ACVSEVNSFTAAFLFSIETQTTIGYGFRCVTDECPIAVFMVVFQSIVGCIIDAFIIGAVM
AKMAKPKKRNETLVFSHNAVIAMRDGKLCLMWRVGNLRKSHLVEAHVRAQLLKSRITSEG
EYIPLDQIDINVGFDSGIDRIFLVSPITIVHEIDEDSPLYDLSKQDIDNADFEIVVILEG
MVEATAMTTQCRSSYLANEILWGHRYEPVLFEEKHYYKVDYSRFHKTYEVPNTPLCSARD
LAEKKYILSNANSFCYENEVALTSKEEDDSENGVPESTSTDTPPDIDLHNQASVPLEPRP
LRRESEI

Ligands and cofactors

ID	Name	Formula	Copies
SR	Strontium ion	Sr	2

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

Primary citation

Cryo-electron microscopy unveils unique structural features of the human Kir2.1 channel. Fernandes, C.A.H., Zuniga, D., Fagnen, C. et al. Sci Adv (2022) 8:eabq8489-eabq8489. DOI 10.1126/sciadv.abq8489 · PubMed

Other PDB entries of the same protein (UniProt P63252 (AlphaFold model), which also has an AlphaFold model), best resolution first:

6SPZ 2.08 Å, Crystal structure of PDZ1-2 from PSD-95 with peptide ligand sequence RRESEI bound to…
8QQL 6.0 Å, Cryo-EM structure of the human inward-rectifier potassium 2.1 channel (Kir2.1) - R312H…

Browse structure collections

About this viewer

MolViewer shows 7ZDZ directly in your browser with nothing to install. Switch between cartoon, ball-and-stick, spacefill and surface views, color by chain, secondary structure or B-factor, measure distances, angles and dihedrals, and share or embed the view.