Annotations: 9NRC

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B [auth L]	Light Chain	IGKV1	Kappa	transmembrane protease serine 6	SAbDab (2026-02-06)
C [auth H]	Heavy Chain	IGHV3	-	transmembrane protease serine 6	SAbDab (2026-02-06)
E [auth C]	Heavy Chain	IGHV3	-	transmembrane protease serine 6	SAbDab (2026-02-06)
D [auth B]	Light Chain	IGKV2	Kappa	transmembrane protease serine 6	SAbDab (2026-02-06)

Thera-SAbDab Antibody Annotation Thera-SAbDab Database Homepage

Chain	Name	Target	Provenance Source
B [auth L]	Exerenibart	TMPRSS6/MT2	Therapeutic SAbDab (2026-02-06)
C [auth H]	Exerenibart	TMPRSS6/MT2	Therapeutic SAbDab (2026-02-06)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF01390	SEA domain (SEA)	SEA domain	Domain found in Sea urchin sperm protein, Enterokinase, Agrin (SEA). Proposed function of regulating or binding carbohydrate side chains. Recently a proteolytic activity has been shown for a SEA domain [4].	Domain
A	PF00057	Low-density lipoprotein receptor domain class A (Ldl_recept_a)	Low-density lipoprotein receptor domain class A	-	Repeat

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Transmembrane protease serine 6	peptidase activity catalytic activity, acting on a protein metalloendopeptidase activity hydrolase activity metallopeptidase activity catalytic activity endopeptidase activity serine hydrolase activity serine-type peptidase activity serine-type endopeptidase activity	intracellular iron ion homeostasis inorganic ion homeostasis cellular homeostasis chemical homeostasis homeostatic process intracellular monoatomic cation homeostasis monoatomic ion homeostasis intracellular chemical homeostasis monoatomic cation homeostasis intracellular monoatomic ion homeostasis regulation of cellular process negative regulation of biological process RNA metabolic process regulation of primary metabolic process intracellular iron ion homeostasis inorganic ion homeostasis cellular homeostasis chemical homeostasis homeostatic process intracellular monoatomic cation homeostasis monoatomic ion homeostasis intracellular chemical homeostasis monoatomic cation homeostasis intracellular monoatomic ion homeostasis regulation of cellular process negative regulation of biological process RNA metabolic process regulation of primary 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 negative regulation of cellular process negative regulation of nucleobase-containing compound metabolic process regulation of nucleobase-containing compound metabolic process regulation of RNA biosynthetic process negative regulation of macromolecule metabolic process regulation of biosynthetic process negative regulation of DNA-templated transcription regulation of biological process negative regulation of metabolic process biological regulation primary metabolic process regulation of macromolecule metabolic process 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 metabolic process cellular process regulation of macromolecule biosynthetic process macromolecule metabolic process regulation of DNA-templated transcription regulation of metabolic process negative regulation of RNA metabolic process collagen catabolic process catabolic process collagen metabolic process proteolysis self proteolysis protein metabolic process cellular response to stimulus cellular response to BMP stimulus cell surface receptor protein serine/threonine kinase signaling pathway cellular response to growth factor stimulus cell surface receptor signaling pathway response to stimulus signaling response to endogenous stimulus cell communication cellular response to endogenous stimulus response to BMP transforming growth factor beta receptor superfamily signaling pathway signal transduction response to growth factor BMP signaling pathway enzyme-linked receptor protein signaling pathway membrane protein proteolysis multicellular organismal-level iron ion homeostasis multicellular organismal process multicellular organismal-level homeostasis multicellular organismal-level chemical homeostasis cellular component organization cellular component disassembly extracellular matrix disassembly extracellular matrix organization cellular component organization or biogenesis extracellular structure organization external encapsulating structure organization negative regulation of signaling regulation of transmembrane receptor protein serine/threonine kinase signaling pathway regulation of signal transduction negative regulation of cellular response to growth factor stimulus negative regulation of BMP signaling pathway negative regulation of cell communication regulation of signaling regulation of BMP signaling pathway negative regulation of response to stimulus regulation of cellular response to growth factor stimulus negative regulation of signal transduction regulation of response to stimulus regulation of cell communication negative regulation of transmembrane receptor protein serine/threonine kinase signaling pathway transcription by RNA polymerase II regulation of transcription by RNA polymerase II negative regulation of transcription by RNA polymerase II positive regulation of DNA-templated transcription positive regulation of biological process positive regulation of macromolecule biosynthetic process positive regulation of metabolic process positive regulation of biosynthetic process positive regulation of macromolecule metabolic process positive regulation of cellular process positive regulation of transcription by RNA polymerase II positive regulation of RNA metabolic process positive regulation of RNA biosynthetic process	cell periphery cellular anatomical structure plasma membrane membrane extracellular region extracellular space
B [auth L]	REGN7999 Fab light chain	-	-	-
C [auth H]	REGN7999 Fab heavy chain	-	-	-
E [auth C]	REGN8023 Fab heavy chain	-	-	-
D [auth B]	REGN8023 Fab light chain	-	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR002172	Low-density lipoprotein (LDL) receptor class A repeat	Repeat
A	IPR035914	Spermadhesin, CUB domain superfamily	Homologous Superfamily
A	IPR036055	LDL receptor-like superfamily	Homologous Superfamily
A	IPR000859	CUB domain	Domain
A	IPR018114	Serine proteases, trypsin family, histidine active site	Active Site
A	IPR043504	Peptidase_S1_PA_chymotrypsin	Unknown
A	IPR009003	Peptidase S1, PA clan	Homologous Superfamily
A	IPR001314	Peptidase S1A, chymotrypsin family	Family
A	IPR033116	Serine proteases, trypsin family, serine active site	Active Site
A	IPR001254	Serine proteases, trypsin domain	Domain
A	IPR036364	SEA domain superfamily	Homologous Superfamily
A	IPR000082	SEA domain	Domain
A	IPR017118	Peptidase S1A, matriptase-2	Family

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A	Pharos: Q8IU80	iron deficiency anemia IRIDA syndrome microcytic anemia congenital anemia Hashimoto thyroiditis intellectual disability Iron-Refractory Iron Deficiency Anemia malignant glioma osteosarcoma sideroblastic anemia hereditary hemochromatosis juvenile idiopathic arthritis pituitary cancer vitiligo Graves disease iron deficiency anemia IRIDA syndrome microcytic anemia congenital anemia Hashimoto thyroiditis intellectual disability Iron-Refractory Iron Deficiency Anemia malignant glioma osteosarcoma sideroblastic anemia hereditary hemochromatosis juvenile idiopathic arthritis pituitary cancer vitiligo Graves disease hypothyroidism large cell medulloblastoma psoriasis

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.