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62  structures 392  species 0  interactions 3681  sequences 37  architectures

Family: Activin_recp (PF01064)

Summary: Activin types I and II receptor domain

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This is the Wikipedia entry entitled "Activin receptor". More...

Activin receptor Edit Wikipedia article

Activin types I and II receptor domain

An Activin receptor is a receptor which binds activin.

Types include:

These proteins are receptor-type kinases of Ser/Thr type, which have a single transmembrane domain and a specific hydrophilic Cys-rich ligand-binding domain.[1][2][3]

Human proteins containing this domain



  1. ^ Wrana JL, Attisano L (1996). "Signal transduction by members of the transforming growth factor-beta superfamily". Cytokine Growth Factor Rev. 7 (4): 327–339. doi:10.1016/S1359-6101(96)00042-1. PMID 9023056.
  2. ^ Wrana JL, Attisano L, Wieser R, Ventura F, Massague J (1994). "Mechanism of activation of the TGF-beta receptor". Nature. 370 (6488): 341–347. doi:10.1038/370341a0. PMID 8047140.
  3. ^ Massague J, Weis-Garcia F (1996). "Serine/threonine kinase receptors: mediators of transforming growth factor beta family signals". Cancer Surv. 27: 41–64. PMID 8909794.

External links

This article incorporates text from the public domain Pfam and InterPro: IPR000472

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

Activin types I and II receptor domain Provide feedback

This Pfam entry consists of both TGF-beta receptor types. This is an alignment of the hydrophilic cysteine-rich ligand-binding domains, Both receptor types, (type I and II) posses a 9 amino acid cysteine box, with the the consensus CCX{4-5}CN. The type I receptors also possess 7 extracellular residues preceding the cysteine box.

Literature references

  1. Baker JC, Harland RM; , Curr Opin Genet Dev 1997;7:467-473.: From receptor to nucleus: the Smad pathway. PUBMED:9309176 EPMC:9309176

  2. Kingsley DM; , Genes Dev 1994;8:133-146.: The TGF-beta superfamily: new members, new receptors, and new genetic tests of function in different organisms. PUBMED:8299934 EPMC:8299934

  3. ten Dijke P, Ichijo H, Franzen P, Schulz P, Saras J, Toyoshima H, Heldin CH, Miyazono K; , Oncogene 1993;8:2879-2887.: Activin receptor-like kinases: a novel subclass of cell-surface receptors with predicted serine/threonine kinase activity. PUBMED:8397373 EPMC:8397373

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR000472

This is a hydrophilic cysteine-rich ligand-binding domain found in both TGF-beta receptor types (type I and II). In both types, this domain posses a 9 amino acid cysteine box, with the the consensus CCX{4-5}CN. The type I receptors also possess 7 extracellular residues preceding the cysteine box [ PUBMED:9309176 , PUBMED:8299934 , PUBMED:8397373 ].

The Transforming growth factor-beta superfamily of ligands include: bone morphogenetic proteins (BMPs), growth and differentiation factors (GDFs), anti-mullerian hormone (AMH), activin, nodal and TGF-beta. Signalling begins with the binding of a TGF-beta superfamily ligand to a TGF-beta type II receptors. The type II receptors phosphorylate and activate type I receptors which autophosphorylate, then bind and activate SMAD transcriptional regulators [ PUBMED:9759503 ].

The receptors for most of the members of this growth factor family are related. They are receptor-type kinases of Ser/Thr type, which have a single transmembrane domain and a specific hydrophilic Cys-rich ligand-binding domain [ PUBMED:9023056 , PUBMED:8047140 , PUBMED:8909794 ].

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan uPAR_Ly6_toxin (CL0117), which has the following description:

This superfamily contains snake toxins as well as extracellular cysteine rich domains.

The clan contains the following 10 members:

Activin_recp BAMBI DUF5746 ecTbetaR2 Ly-6_related PLA2_inh QVR Toxin_TOLIP UPAR_LY6 UPAR_LY6_2


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

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Seed source: Pfam-B_338 (release 3.0)
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Finn RD , Bateman A , Griffiths-Jones SR
Number in seed: 16
Number in full: 3681
Average length of the domain: 83.40 aa
Average identity of full alignment: 27 %
Average coverage of the sequence by the domain: 15.09 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 20.9 20.9
Trusted cut-off 20.9 20.9
Noise cut-off 20.8 20.8
Model length: 83
Family (HMM) version: 25
Download: download the raw HMM for this family

Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the Activin_recp domain has been found. There are 62 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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