6O3C | pdb_00006o3c

Crystal structure of active Smoothened bound to SAG21k, cholesterol, and NbSmo8

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Membrane Protein Annotation: OPM
Membrane Protein Annotation: PDBTM
Membrane Protein Annotation: mpstruc

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
B	V-set_8	e6o3cB1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_8	ECOD (1.6)
A	Frizzled	e6o3cA1	A: alpha bundles	X: Family A G protein-coupled receptor-like (From Topology)	H: Family A G protein-coupled receptor-like (From Topology)	T: Family A G protein-coupled receptor-like	F: Frizzled	ECOD (1.6)
A	Fz	e6o3cA2	A: few secondary structure elements	X: Frizzled cysteine-rich domain-related (From Topology)	H: Frizzled cysteine-rich domain-related (From Topology)	T: Frizzled cysteine-rich domain-related	F: Fz	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	1.20.1070.10	Mainly Alpha	Up-down Bundle	Rhopdopsin 7-helix transmembrane proteins	Rhodopsin 7-helix transmembrane proteins	CATH (utative)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B	Heavy Chain	IGHV1	-	smoothened homolog	SAbDab (2025-10-17)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF01392	Fz domain (Fz)	Fz domain	Also known as the CRD (cysteine rich domain), the C6 box in MuSK receptor. This domain of unknown function has been independently identified by several groups [1,2,3,4]. The domain contains 10 conserved cysteines.	Domain
A	PF01534	Frizzled/Smoothened family membrane region (Frizzled)	Frizzled/Smoothened family membrane region	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
B	NbSmo8	-	-	-
A	Smoothened homolog	patched binding protein binding binding signaling receptor binding enzyme regulator activity enzyme inhibitor activity protein kinase regulator activity cAMP-dependent protein kinase regulator activity protein kinase inhibitor activity molecular function inhibitor activity molecular function regulator activity cAMP-dependent protein kinase inhibitor activity protein serine/threonine kinase inhibitor activity kinase inhibitor activity patched binding protein binding binding signaling receptor binding enzyme regulator activity enzyme inhibitor activity protein kinase regulator activity cAMP-dependent protein kinase regulator activity protein kinase inhibitor activity molecular function inhibitor activity molecular function regulator activity cAMP-dependent protein kinase inhibitor activity protein serine/threonine kinase inhibitor activity kinase inhibitor activity kinase regulator activity sterol binding oxysterol binding steroid binding lipid binding molecular transducer activity G protein-coupled receptor activity transmembrane signaling receptor activity signaling receptor activity molecular sequestering activity protein sequestering activity protein kinase A catalytic subunit binding protein kinase A binding kinase binding enzyme binding protein kinase binding	cellular response to stimulus response to sterol response to stimulus response to lipid response to alcohol response to oxygen-containing compound response to cholesterol cellular response to oxygen-containing compound cellular response to chemical stimulus cellular response to alcohol response to chemical cellular response to lipid cellular process cellular response to sterol cellular response to stimulus response to sterol response to stimulus response to lipid response to alcohol response to oxygen-containing compound response to cholesterol cellular response to oxygen-containing compound cellular response to chemical stimulus cellular response to alcohol response to chemical cellular response to lipid cellular process cellular response to sterol cellular response to cholesterol developmental process multicellular organism development multicellular organismal process anatomical structure development pattern specification process regulation of protein stability biological regulation regulation of biological quality protein stabilization dorsal/ventral pattern formation regionalization apoptotic process cell death programmed cell death regulation of cellular process regulation of protein modification process regulation of protein phosphorylation negative regulation of biological process negative regulation of phosphate metabolic process regulation of primary metabolic process regulation of phosphate metabolic process phosphate-containing compound metabolic process negative regulation of protein modification process negative regulation of cellular process protein metabolic process protein modification process phosphorus metabolic process negative regulation of protein metabolic process negative regulation of macromolecule metabolic process regulation of biological process protein phosphorylation phosphorylation regulation of protein metabolic process negative regulation of metabolic process primary metabolic process regulation of macromolecule metabolic process negative regulation of protein phosphorylation macromolecule modification negative regulation of phosphorus metabolic process metabolic process regulation of phosphorylation regulation of phosphorus metabolic process macromolecule metabolic process negative regulation of phosphorylation regulation of metabolic process epithelium development epidermis development molting cycle process hair cycle epidermis morphogenesis animal organ development morphogenesis of an epithelium tissue development tissue morphogenesis anatomical structure morphogenesis skin development skin epidermis development hair follicle development molting cycle hair cycle process hair follicle morphogenesis cellular developmental process astrocyte differentiation cell development astrocyte activation glial cell development neurogenesis astrocyte development gliogenesis cell differentiation response to stress system development defense response cell activation nervous system development central nervous system development glial cell differentiation glial cell activation inflammatory response neuroinflammatory response head development brain morphogenesis forebrain development brain development forebrain morphogenesis animal organ morphogenesis ossification endocrine system development type B pancreatic cell development epithelial cell differentiation epithelial cell development pancreas development endocrine pancreas development enteroendocrine cell differentiation type B pancreatic cell differentiation RNA metabolic process negative regulation of RNA biosynthetic process RNA biosynthetic process nucleobase-containing compound metabolic process DNA-templated transcription nucleic acid biosynthetic process regulation of RNA metabolic process transcription by RNA polymerase II negative regulation of nucleobase-containing compound metabolic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process regulation of biosynthetic process regulation of transcription by RNA polymerase II negative regulation of DNA-templated transcription negative regulation of transcription by RNA polymerase II nucleobase-containing compound biosynthetic process gene expression macromolecule biosynthetic process nucleic acid metabolic process regulation of gene expression biosynthetic process negative regulation of biosynthetic process negative regulation of macromolecule biosynthetic process regulation of macromolecule biosynthetic process regulation of DNA-templated transcription negative regulation of RNA metabolic process multicellular organism growth developmental growth growth regulation of somatic stem cell population maintenance regulation of developmental process regulation of stem cell population maintenance stem cell population maintenance somatic stem cell population maintenance regulation of multicellular organismal process maintenance of cell number heart development cardiac atrium morphogenesis cardiac chamber morphogenesis heart morphogenesis cardiac atrium development circulatory system development cardiac septum development cardiac septum morphogenesis cardiac chamber development atrial septum morphogenesis atrial septum development mesonephric epithelium development kidney epithelium development branching morphogenesis of an epithelial tube nephron tubule morphogenesis regulation of kidney development regulation of branching involved in ureteric bud morphogenesis positive regulation of developmental process tube morphogenesis nephron development regulation of morphogenesis of a branching structure regulation of animal organ morphogenesis positive regulation of multicellular organismal process mesonephric tubule development renal tubule morphogenesis nephron morphogenesis nephron epithelium morphogenesis positive regulation of biological process nephron tubule development renal system development ureteric bud morphogenesis positive regulation of morphogenesis of an epithelium branching involved in ureteric bud morphogenesis renal tubule development regulation of morphogenesis of an epithelium epithelial tube morphogenesis regulation of anatomical structure morphogenesis nephron epithelium development ureteric bud development tube development mesonephros development kidney morphogenesis morphogenesis of a branching structure positive regulation of branching involved in ureteric bud morphogenesis mesonephric tubule morphogenesis kidney development morphogenesis of a branching epithelium negative regulation of programmed cell death regulation of apoptotic process regulation of programmed cell death negative regulation of apoptotic process generation of neurons central nervous system neuron differentiation neuron differentiation positive regulation of cell communication positive regulation of signal transduction signaling regulation of signal transduction cell communication positive regulation of response to stimulus positive regulation of smoothened signaling pathway signal transduction positive regulation of cellular process regulation of smoothened signaling pathway regulation of signaling cell surface receptor signaling pathway smoothened signaling pathway regulation of response to stimulus regulation of cell communication positive regulation of signaling positive regulation of mesenchymal cell proliferation cell population proliferation positive regulation of cell population proliferation regulation of mesenchymal cell proliferation regulation of cell population proliferation mesenchymal cell proliferation diencephalon development thalamus development left/right axis specification left/right pattern formation axis specification regulation of heart morphogenesis epithelial cell proliferation blood vessel morphogenesis vasculogenesis vasculature development blood vessel development mesenchymal to epithelial transition involved in renal vesicle formation renal vesicle morphogenesis metanephric renal vesicle morphogenesis renal vesicle development metanephros development metanephric renal vesicle formation metanephros morphogenesis metanephric nephron development mesenchymal to epithelial transition involved in metanephric renal vesicle formation mesenchymal to epithelial transition involved in metanephros morphogenesis epithelial cell differentiation involved in kidney development mesenchymal to epithelial transition metanephric nephron morphogenesis cell differentiation involved in metanephros development cell differentiation involved in kidney development anatomical structure formation involved in morphogenesis renal vesicle formation positive regulation of locomotion regulation of cell motility positive regulation of cell migration regulation of locomotion positive regulation of cell motility regulation of cell migration cell migration cell motility locomotion regulation of growth regulation of developmental growth positive regulation of organ growth organ growth positive regulation of growth regulation of organ growth positive regulation of developmental growth response to inositol negative regulation of gene expression lateral mesoderm development mesenchyme development determination of left/right asymmetry in lateral mesoderm determination of bilateral symmetry determination of left/right symmetry mesoderm development specification of symmetry dopaminergic neuron differentiation somite development embryo development cell fate specification cell fate commitment neuroblast proliferation neural precursor cell proliferation digestive system development midgut development digestive tract development regulation of localization localization multicellular organismal-level homeostasis homeostatic process homeostasis of number of cells within a tissue anatomical structure homeostasis tissue homeostasis homeostasis of number of cells mammary gland epithelial cell differentiation mammary gland development gland development mammary gland epithelium development cell-cell signaling epithelial-mesenchymal cell signaling muscle cell migration myoblast migration positive regulation of macromolecule biosynthetic process positive regulation of metabolic process positive regulation of gene expression positive regulation of biosynthetic process positive regulation of macromolecule metabolic process pancreas morphogenesis cerebellum morphogenesis cerebellar cortex morphogenesis hindbrain morphogenesis cerebellar cortex development cerebellum development metencephalon development hindbrain development establishment of protein localization cellular localization nitrogen compound transport nucleocytoplasmic transport transport nuclear transport intracellular transport protein localization to nucleus establishment of localization import into nucleus establishment of protein localization to organelle protein transport establishment of localization in cell macromolecule localization protein localization to organelle protein import into nucleus intracellular protein localization intracellular protein transport regulation of protein localization positive regulation of nucleocytoplasmic transport positive regulation of establishment of protein localization regulation of protein localization to nucleus positive regulation of protein transport regulation of protein import into nucleus positive regulation of intracellular transport regulation of intracellular transport regulation of transport positive regulation of protein localization to nucleus regulation of establishment of protein localization positive regulation of protein import into nucleus regulation of nucleocytoplasmic transport regulation of protein transport positive regulation of transport regulation of cellular localization positive regulation of protein localization regulation of intracellular protein transport positive regulation of intracellular protein transport embryo development ending in birth or egg hatching chordate embryonic development in utero embryonic development embryonic organ development pallium development cerebral cortex development telencephalon development neural tube development dorsal/ventral neural tube patterning neural tube patterning positive regulation of DNA-templated transcription positive regulation of nucleobase-containing compound metabolic process positive regulation of transcription by RNA polymerase II positive regulation of RNA metabolic process positive regulation of RNA biosynthetic process embryonic heart tube development embryonic heart tube morphogenesis heart looping embryonic organ morphogenesis embryonic morphogenesis determination of heart left/right asymmetry osteoblast differentiation myotube cell development skeletal muscle fiber development skeletal muscle tissue development muscle cell differentiation myotube differentiation striated muscle tissue development muscle structure development skeletal muscle organ development striated muscle cell development muscle cell development muscle tissue development muscle organ development striated muscle cell differentiation odontogenesis of dentin-containing tooth odontogenesis ventral midline determination ventral midline development regulation of cell differentiation regulation of epithelial cell differentiation negative regulation of cell differentiation regulation of multicellular organismal development negative regulation of epithelial cell differentiation negative regulation of developmental process spinal cord dorsal/ventral patterning spinal cord development spinal cord patterning positive regulation of epithelial cell proliferation regulation of epithelial cell proliferation stem cell development neural crest cell differentiation neural crest cell development mesenchymal cell migration stem cell differentiation ameboidal-type cell migration mesenchymal cell differentiation neural crest cell migration regulation of multicellular organism growth positive regulation of multicellular organism growth dentate gyrus development hippocampus development limbic system development smooth muscle tissue development regulation of molecular function regulation of DNA binding regulation of binding negative regulation of binding negative regulation of molecular function negative regulation of DNA binding regulation of hair cycle regulation of hair follicle development negative regulation of hair follicle development negative regulation of multicellular organismal process detection of stimulus contact inhibition detection of cell density detection of biotic stimulus response to biotic stimulus positive regulation of nervous system development regulation of neuroblast proliferation regulation of neurogenesis regulation of cell development regulation of nervous system development positive regulation of cell differentiation positive regulation of neurogenesis regulation of neural precursor cell proliferation positive regulation of cell development positive regulation of neural precursor cell proliferation positive regulation of neuroblast proliferation anterior/posterior pattern specification	intracellular organelle microtubule organizing center cellular anatomical structure intracellular anatomical structure cytoskeleton organelle membraneless organelle centriole intracellular membraneless organelle microtubule cytoskeleton membrane microdomain cell periphery membrane raft plasma membrane raft intracellular organelle microtubule organizing center cellular anatomical structure intracellular anatomical structure cytoskeleton organelle membraneless organelle centriole intracellular membraneless organelle microtubule cytoskeleton membrane microdomain cell periphery membrane raft plasma membrane raft membrane plasma membrane plasma membrane region caveola membrane-bounded organelle cilium ciliary membrane plasma membrane bounded cell projection cell projection bounding membrane of organelle organelle membrane cell projection membrane endosome intracellular vesicle intracellular membrane-bounded organelle endomembrane system cytoplasmic vesicle late endosome cytoplasm vesicle cytoplasmic vesicle membrane vesicle membrane endocytic vesicle membrane endocytic vesicle Golgi apparatus endoplasmic reticulum-Golgi intermediate compartment non-motile cilium 9+0 non-motile cilium endoplasmic reticulum

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR036790	Frizzled cysteine-rich domain superfamily	Homologous Superfamily
A	IPR041771	Smoothened, cysteine-rich domain	Domain
A	IPR017981	GPCR, family 2-like, 7TM	Domain
A	IPR020067	Frizzled domain	Domain
A	IPR035683	Smoothened, 7TM	Domain
A	IPR015526	Frizzled/secreted frizzled-related protein	Family
A	IPR000539	Frizzled/Smoothened, 7TM	Domain

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A	OPM	Transmembrane	Alpha-helical polytopic	Rhodopsin-like receptors and pumps	Frizzled/Smoothened family

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	G Protein-Coupled Receptors: Class F	Smoothened (SMO) receptor bound to SAG21k, cholesterol, and NbSmo8

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.