Annotations: 4P59

HER3 extracellular domain in complex with Fab fragment of MOR09825

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
IMGT Antibody Annotation
SAbDab Antibody Annotation
Thera-SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	GDI	e4p59A1	A: alpha arrays	X: Lipocalins/Streptavidin	H: Enterocin 7A and 7B	T: Enterocin 7A and 7B	F: GDI	ECOD (v295.2)
B [auth H]	AAA_23	e4p59H1	A: alpha arrays	X: DEATH domain	H: 6-phosphogluconate dehydrogenase C-terminal domain-like	T: 6-phosphogluconate dehydrogenase C-terminal domain-like	F: AAA_23	ECOD (v295.2)
C [auth L]	AAA_23	e4p59L1	A: alpha arrays	X: DEATH domain	H: 6-phosphogluconate dehydrogenase C-terminal domain-like	T: 6-phosphogluconate dehydrogenase C-terminal domain-like	F: AAA_23	ECOD (v295.2)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.80.20.20	Alpha Beta	Alpha-Beta Horseshoe	24 nucleotide stem-loop, u2 snrnp hairpin iv. U2 a'	Chain A	CATH (4.3.0)
A	2.10.220.10	Mainly Beta	Ribbon	Hormone Receptor, Insulin-like Growth Factor Receptor 1	Chain A domain 2	CATH (4.3.0)
B [auth H]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
C [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)

IMGT Antibody Annotation IMGT Database Homepage

Chain	Protein Name	Description	Organism Name	Gene Allele Name(s)	Domain Name(s)	Receptor Type	Receptor Description	Provenance Source
B [auth H]	MOR09825 Fab	VH-CH1	Homo sapiens (human)	IGHV3-6404, IGHV3-2304, IGHJ302, IGHG101, IGHG102, IGHG104	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_KAPPA	IMGT (202640-0)
C [auth L]	MOR09825 Fab	L-KAPPA	Homo sapiens (human)	IGKV1-1201, IGKV1D-1201, IGKV1-1202, IGKV1D-1202, IGKJ101, IGKC01	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-1_KAPPA	IMGT (202640-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B [auth H]	Heavy Chain	IGHV3	-	receptor tyrosine-protein kinase erbb-3	SAbDab (2026-10-16)
C [auth L]	Light Chain	IGKV1	Kappa	receptor tyrosine-protein kinase erbb-3	SAbDab (2026-10-16)

Thera-SAbDab Antibody Annotation Thera-SAbDab Database Homepage

Chain	Name	Target	Provenance Source
B [auth H]	Elgemtumab	ERBB3/HER3	Therapeutic SAbDab (2026-10-16)
C [auth L]	Elgemtumab	ERBB3/HER3	Therapeutic SAbDab (2026-10-16)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF00757	Furin-like cysteine rich region (Furin-like)	Furin-like cysteine rich region		Domain
A	PF01030	Receptor L domain (Recep_L_domain)	Receptor L domain	-	Repeat
A	PF14843	Growth factor receptor domain IV (GF_recep_IV)	Growth factor receptor domain IV	This is the fourth extracellular domain of receptor tyrosine protein kinases. Interaction between this domain and the furin-like domain (Pfam:PF00757) regulates the binding of ligands to the receptor L domains (Pfam:PF01030) [1].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	Receptor tyrosine-protein kinase erbB-3	protein tyrosine kinase activator activity enzyme regulator activity kinase activator activity enzyme activator activity molecular function activator activity molecular function regulator activity protein kinase activator activity protein kinase regulator activity kinase regulator activity neuregulin binding protein binding binding growth factor binding molecular transducer activity protein tyrosine kinase activator activity enzyme regulator activity kinase activator activity enzyme activator activity molecular function activator activity molecular function regulator activity protein kinase activator activity protein kinase regulator activity kinase regulator activity neuregulin binding protein binding binding growth factor binding molecular transducer activity transmembrane signaling receptor activity signaling receptor activity neuregulin receptor activity protein tyrosine kinase activity catalytic activity, acting on a protein kinase activity protein kinase activity transferase activity catalytic activity phosphotransferase activity, alcohol group as acceptor transferase activity, transferring phosphorus-containing groups adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding ubiquitin protein ligase binding ubiquitin-like protein ligase binding enzyme binding identical protein binding protein heterodimerization activity protein dimerization activity signaling receptor binding ErbB-3 class receptor binding	cellular response to stimulus regulation of signaling regulation of biological process regulation of cellular process response to stimulus negative regulation of signaling signaling negative regulation of response to stimulus biological regulation negative regulation of biological process regulation of signal transduction negative regulation of signal transduction negative regulation of cell communication cell communication regulation of response to stimulus cellular response to stimulus regulation of signaling regulation of biological process regulation of cellular process response to stimulus negative regulation of signaling signaling negative regulation of response to stimulus biological regulation negative regulation of biological process regulation of signal transduction negative regulation of signal transduction negative regulation of cell communication cell communication regulation of response to stimulus negative regulation of cellular process regulation of cell communication cellular process signal transduction developmental process heart development multicellular organism development multicellular organismal process anatomical structure development animal organ development animal gross anatomical part developmental process circulatory system development system development regulation of localization regulation of transport transport secretion negative regulation of transport establishment of localization regulation of secretion localization negative regulation of secretion ERBB2 signaling pathway cell surface receptor signaling pathway ERBB2-ERBB3 signaling pathway cell surface receptor protein tyrosine kinase signaling pathway ERBB signaling pathway ERBB3 signaling pathway enzyme-linked receptor protein signaling pathway signal transduction in absence of ligand cell death extrinsic apoptotic signaling pathway apoptotic signaling pathway extrinsic apoptotic signaling pathway in absence of ligand apoptotic process programmed cell death positive regulation of cell communication positive regulation of signal transduction positive regulation of biological process intracellular signal transduction positive regulation of response to stimulus positive regulation of JNK cascade regulation of intracellular signal transduction JNK cascade intracellular signaling cassette positive regulation of cellular process positive regulation of MAPK cascade regulation of JNK cascade positive regulation of intracellular signal transduction regulation of MAPK cascade MAPK cascade positive regulation of signaling epidermal growth factor receptor signaling pathway cell adhesion regulation of cell adhesion negative regulation of cell adhesion phosphatidylinositol 3-kinase/protein kinase B signal transduction negative regulation of programmed cell death regulation of apoptotic process regulation of programmed cell death negative regulation of apoptotic process cellular developmental process peripheral nervous system development cell development nervous system development glial cell development neurogenesis Schwann cell development gliogenesis glial cell differentiation cell differentiation Schwann cell differentiation cellular component organization cell junction organization neuromuscular junction development synapse organization cellular component organization or biogenesis cell population proliferation positive regulation of cell population proliferation positive regulation of epithelial cell proliferation regulation of cell population proliferation regulation of epithelial cell proliferation epithelial cell proliferation generation of neurons neuron differentiation regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction positive regulation of phosphatidylinositol 3-kinase/protein kinase B signal transduction neuron apoptotic process negative regulation of neuron apoptotic process regulation of neuron apoptotic process nerve development cranial nerve development wound healing response to stress response to wounding myelination axon ensheathment ensheathment of neurons	cell periphery postsynapse cellular anatomical structure postsynaptic membrane synapse cell junction membrane plasma membrane plasma membrane region synaptic membrane protein-containing complex plasma membrane protein complex plasma membrane signaling receptor complex membrane protein complex cell periphery postsynapse cellular anatomical structure postsynaptic membrane synapse cell junction membrane plasma membrane plasma membrane region synaptic membrane protein-containing complex plasma membrane protein complex plasma membrane signaling receptor complex membrane protein complex signaling receptor complex ERBB3:ERBB2 complex basal part of cell basal plasma membrane basolateral plasma membrane apical part of cell apical plasma membrane extracellular region lateral plasma membrane
B [auth H]	MOR09825 Fab fragment heavy chain	-	-	-
C [auth L]	MOR09825 Fab fragment light chain	-	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR016245	Tyrosine protein kinase, EGF/ERB/XmrK receptor	Family
A	IPR000719	Protein kinase domain	Domain
A	IPR036941	Receptor L-domain superfamily	Homologous Superfamily
A	IPR032778	Growth factor receptor domain 4	Domain
A	IPR006212	Furin-like repeat	Repeat
A	IPR000494	Receptor L-domain	Domain
A	IPR001245	Serine-threonine/tyrosine-protein kinase, catalytic domain	Domain
A	IPR011009	Protein kinase-like domain superfamily	Homologous Superfamily
A	IPR006211	Furin-like cysteine-rich domain	Domain
A	IPR009030	Growth factor receptor cysteine-rich domain superfamily	Homologous Superfamily
A	IPR050122	Receptor Tyrosine Kinase	Family

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A	: P21860	lethal congenital contracture syndrome 2 breast cancer nasopharyngeal carcinoma Neoplasm Metastasis prostate cancer gallbladder cancer breast carcinoma alopecia areata cutaneous lupus erythematosus urinary bladder neoplasm ductal breast carcinoma in situ gastric adenocarcinoma osteosarcoma glioblastoma pancreatic ductal adenocarcinoma lethal congenital contracture syndrome 2 breast cancer nasopharyngeal carcinoma Neoplasm Metastasis prostate cancer gallbladder cancer breast carcinoma alopecia areata cutaneous lupus erythematosus urinary bladder neoplasm ductal breast carcinoma in situ gastric adenocarcinoma osteosarcoma glioblastoma pancreatic ductal adenocarcinoma acute erythroleukemia, familial head and neck carcinoma pancreatic intraductal papillary-mucinous neoplasm with low grade dysplasia anorexia nervosa invasive ductal breast carcinoma pituitary cancer attention deficit hyperactivity disorder, inattentive type lung adenocarcinoma bipolar disorder rheumatoid arthritis cancer malignant glioma skin neoplasm cleft lip subependymal giant cell astrocytoma cystic fibrosis urinary bladder cancer Down syndrome vitiligo gastric carcinoma ovarian cancer Hashimoto thyroiditis pancreatic intraductal papillary-mucinous carcinoma allergic rhinitis head and neck neoplasm Pick disease arthrogryposis large cell medulloblastoma polycystic ovary syndrome atypical teratoid rhabdoid tumor lung benign neoplasm bladder benign neoplasm major depressive disorder schizophrenia carcinoma spina bifida colon carcinoma malignant pancreatic neoplasm ulcerative colitis medulloblastoma urinary bladder carcinoma Duchenne muscular dystrophy gallbladder neoplasm gastric neoplasm ovarian mucinous adenocarcinoma head and neck cancer pancreatic intraductal papillary-mucinous neoplasm interstitial cystitis pilocytic astrocytoma asthma progressive supranuclear palsy benign neoplasm of stomach lung cancer bladder carcinoma in situ malignant ependymoma skin cancer breast fibroadenoma cholangiocarcinoma stomach carcinoma in situ