Annotations: 8RMN

Cryo-EM structure of a dimer of decameric human CALHM4 in complex with synthetic nanobody SbC4

External Resource: Annotation

Domain Annotation: ECOD Classification
SAbDab Antibody Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations
Membrane Protein Annotation: PDBTM

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
B [auth U]	HAT_Syf1_CNRKL1_C	e8rmnU01	A: beta barrels	X: cradle loop barrel	H: RIFT-related	T: acid protease	F: HAT_Syf1_CNRKL1_C	ECOD (v294.2)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
AA [auth a], B [auth U], BA [auth b], CA [auth c], DA [auth d], AA [auth a], B [auth U], BA [auth b], CA [auth c], DA [auth d], EA [auth e], FA [auth f], GA [auth g], HA [auth h], IA [auth i], JA [auth j], KA [auth k], LA [auth l], MA [auth m], NA [auth n], V, W, X, Y, Z	Heavy Chain	IGHV1	-	synthetic nanobody sbc4, calcium homeostasis modulator protein 4	SAbDab (2026-05-08)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
AA [auth a], B [auth U], BA [auth b], CA [auth c], DA [auth d], AA [auth a], B [auth U], BA [auth b], CA [auth c], DA [auth d], EA [auth e], FA [auth f], GA [auth g], HA [auth h], IA [auth i], JA [auth j], KA [auth k], LA [auth l], MA [auth m], NA [auth n], V, W, X, Y, Z	Synthetic nanobody SbC4	-	-	-
A, C [auth B], D [auth C], E [auth D], F [auth E], A, C [auth B], D [auth C], E [auth D], F [auth E], G [auth F], H [auth G], I [auth H], J [auth I], K [auth J], L [auth K], M [auth L], N [auth M], O [auth N], P [auth O], Q [auth P], R [auth Q], S [auth R], T [auth S], U [auth T]	Calcium homeostasis modulator protein 4	monoatomic cation transmembrane transporter activity monoatomic cation channel activity passive transmembrane transporter activity monoatomic ion channel activity channel activity monoatomic ion transmembrane transporter activity transporter activity transmembrane transporter activity	ATP transport nitrogen compound transport organic anion transport nucleotide transport transport purine ribonucleotide transport carbohydrate derivative transport establishment of localization purine nucleotide transport adenine nucleotide transport localization ATP export nucleobase-containing compound transport organophosphate ester transport	cell periphery cellular anatomical structure plasma membrane membrane

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, C [auth B], D [auth C], E [auth D], F [auth E], A, C [auth B], D [auth C], E [auth D], F [auth E], G [auth F], H [auth G], I [auth H], J [auth I], K [auth J], L [auth K], M [auth L], N [auth M], O [auth N], P [auth O], Q [auth P], R [auth Q], S [auth R], T [auth S], U [auth T]	IPR029569	Calcium homeostasis modulator family	Family

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A, C [auth B], D [auth C], E [auth D], F [auth E], A, C [auth B], D [auth C], E [auth D], F [auth E], G [auth F], H [auth G], I [auth H], J [auth I], K [auth J], L [auth K], M [auth L], N [auth M], O [auth N], P [auth O], Q [auth P], R [auth Q], S [auth R], T [auth S], U [auth T]	: Q5JW98	nephrotic syndrome ulcerative colitis

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A, C [auth B], D [auth C], E [auth D], F [auth E] A, C [auth B], D [auth C], E [auth D], F [auth E], G [auth F], H [auth G], I [auth H], J [auth I], K [auth J], L [auth K], M [auth L], N [auth M], O [auth N], P [auth O], Q [auth P], R [auth Q], S [auth R], T [auth S], U [auth T]	PDBTM	Annotated as membrane protein by PDBTM

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RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.