Protein / target
Activin receptor type-2B
Protein at a glance
Biological role
Protein serine/threonine/tyrosine kinase activity
Primary system
Nervous system
Strongest disease association
Heterotaxia
Therapeutic maturity
Clinically validated target
Druggability
Small molecule
Clinical development
1 approved · 1 in clinical development
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function
Transmembrane serine/threonine kinase activin type-2 receptor forming an activin receptor complex with activin type-1 serine/threonine kinase receptors (ACVR1, ACVR1B or ACVR1c). Transduces the activin signal from the cell surface to the cytoplasm and is thus regulating many physiological and pathological processes including neuronal differentiation and neuronal survival, hair follicle development and cycling, FSH production by the pituitary gland, wound healing, extracellular matrix production, immunosuppression and carcinogenesis. Activin is also thought to have a paracrine or autocrine role in follicular development in the ovary. Within the receptor complex, the type-2 receptors act as a primary activin receptors (binds activin-A/INHBA, activin-B/INHBB as well as inhibin-A/INHA-INHBA). The type-1 receptors like ACVR1B act as downstream transducers of activin signals. Activin binds to type-2 receptor at the plasma membrane and activates its serine-threonine kinase. The activated receptor type-2 then phosphorylates and activates the type-1 receptor. Once activated, the type-1 receptor binds and phosphorylates the SMAD proteins SMAD2 and SMAD3, on serine residues of the C-terminal tail. Soon after their association with the activin receptor and subsequent phosphorylation, SMAD2 and SMAD3 are released into the cytoplasm where they interact with the common partner SMAD4. This SMAD complex translocates into the nucleus where it mediates activin-induced transcription. Inhibitory SMAD7, which is recruited to ACVR1B through FKBP1A, can prevent the association of SMAD2 and SMAD3 with the activin receptor complex, thereby blocking the activin signal. Activin signal transduction is also antagonized by the binding to the receptor of inhibin-B via the IGSF1 inhibin coreceptor
Subcellular location
Domains and Gene Ontology detail (38)Hide
Domains & features
Gene Ontology
- Cactivin receptor complex
- Ccytoplasm
- Cplasma membrane
- Cprotein-containing complex
- Creceptor complex
- Factivin binding
- Factivin receptor activity
- Factivin receptor activity, type II
- FATP binding
- Fgrowth factor binding
- Fkinase activator activity
- Fmetal ion binding
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
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Kinase signalling
- ·Transmembrane serine/threonine kinase activin type-2 receptor forming an activin recepto…
- ·protein serine/threonine kinase activity
- ·protein serine/threonine/tyrosine kinase activity
Transcriptional regulation
- ·Transmembrane serine/threonine kinase activin type-2 receptor forming an activin recepto…
- ·negative regulation of transcription by RNA polymerase II
- ·regulation of DNA-templated transcription
Immune signalling
- ·trophoblast cell migration
Cell adhesion
- ·Transmembrane serine/threonine kinase activin type-2 receptor forming an activin recepto…
View underlying pathways (4)Hide underlying pathways
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Interaction neighbourhood
Proteins with the strongest functional or physical association. Node size and line weight reflect STRING confidence; hover or select a partner to inspect one association.
Functional and physical associations from STRING v12.0. Only associations with this protein are drawn — partner-to-partner links are not part of this evidence.
Drugs targeting this protein
Whether each drug engages this protein directly or through a complex, and how many other targets are recorded for it. Direct binders with few recorded targets are listed first.
Activin receptor type-2B antagonist
Appears in clinical studies involving inclusion body myositis, acute myeloid leukemia by FAB classification, inclusion body myositis, muscle atrophy
ChEMBL mechanism, action type and target identity. Open Targets clinical status and indications.
Translational evidence
Why this target matters therapeutically — disease associations, drugs in development, tractability and safety, from Open Targets.
Strongest genetic associations
Human genetic evidence — the most direct causal link between this target and a disease.
Highest-confidence therapeutic associations
Diseases where a drug acting on this target has already reached clinical development.
Highest overall evidence
Remaining associations by Open Targets' aggregated evidence score.
Show all associationsHide all associations
Open Targets ranks 1,338 associations for this target and we store the top 10 by aggregated score. The long tail is largely literature co-mention and RNA-expression evidence, not evidence that this target drives those diseases.
Known drugs · 2 total
inclusion body myositis · acute myeloid leukemia by FAB classification · inclusion body myositis
spinal fusion · bone disorder · osteoporosis
Tractability
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein.
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ClinicalTrials.gov via the drug-target graph.
Forefront confidence
Our own weighting of the evidence behind each disease association. Human genetics and clinical evidence count for most; literature co-mention counts for little, because two entities sharing an abstract is not evidence that one drives the other.
The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the underlying per-type scores are shown above so the calculation can be checked.
What's happening now
Recent activity around this target, drawn from one canonical event stream. Every item is reached through a drug that targets this protein, so each event is news about that drug rather than about the protein directly.
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.