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138  structures 470  species 0  interactions 12890  sequences 287  architectures

Family: HRM (PF02793)

Summary: Hormone receptor domain

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Hormone receptor domain Provide feedback

This extracellular domain contains four conserved cysteines that probably for disulphide bridges. The domain is found in a variety of hormone receptors. It may be a ligand binding domain.

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR001879

The secretin-like GPCRs include secretin [ PUBMED:1646711 ], calcitonin [ PUBMED:1658940 ], parathyroid hormone/parathyroid hormone-related peptides [ PUBMED:1658941 ] and vasoactive intestinal peptide [ PUBMED:1314625 ], all of which activate adenylyl cyclase and the phosphatidyl-inositol-calcium pathway. These receptors contain seven transmembrane regions, in a manner reminiscent of the rhodopsins and other receptors believed to interact with G-proteins (however there is no significant sequence identity between these families, the secretin-like receptors thus bear their own unique '7TM' signature). Their N-terminal is probably located on the extracellular side of the membrane and potentially glycosylated. This N-terminal region contains a long conserved region which allows the binding of large peptidic ligand such as glucagon, secretin, VIP and PACAP; this region contains five conserved cysteines residues which could be involved in disulphide bond. The C-terminal region of these receptor is probably cytoplasmic. Every receptor gene in this family is encoded on multiple exons, and several of these genes are alternatively spliced to yield functionally distinct products.

G protein-coupled receptors (GPCRs) constitute a vast protein family that encompasses a wide range of functions, including various autocrine, paracrine and endocrine processes. They show considerable diversity at the sequence level, on the basis of which they can be separated into distinct groups [ PUBMED:12679517 ]. The term clan can be used to describe the GPCRs, as they embrace a group of families for which there are indications of evolutionary relationship, but between which there is no statistically significant similarity in sequence [ PUBMED:8170923 ]. The currently known clan members include rhodopsin-like GPCRs (Class A, GPCRA), secretin-like GPCRs (Class B, GPCRB), metabotropic glutamate receptor family (Class C, GPCRC), fungal mating pheromone receptors (Class D, GPCRD), cAMP receptors (Class E, GPCRE) and frizzled/smoothened (Class F, GPCRF) [ PUBMED:8170923 , PUBMED:8081729 , PUBMED:15914470 , PUBMED:18948278 , PUBMED:16753280 ]. GPCRs are major drug targets, and are consequently the subject of considerable research interest. It has been reported that the repertoire of GPCRs for endogenous ligands consists of approximately 400 receptors in humans and mice [ PUBMED:12679517 ]. Most GPCRs are identified on the basis of their DNA sequences, rather than the ligand they bind, those that are unmatched to known natural ligands are designated by as orphan GPCRs, or unclassified GPCRs [ PUBMED:23020293 ].

This domain is found in the extracellular part of some of the secretin-like (family 2) GPCRs including the calcitonin receptor; corticotropin releasing factor receptor 1; diuretic hormone receptor; glucagon-like peptide 1 receptor; and parathyroid hormone peptide receptor.

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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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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We make a range of alignments for each Pfam-A family. You can see a description of each above. You can view these alignments in various ways but please note that some types of alignment are never generated while others may not be available for all families, most commonly because the alignments are too large to handle.

Representative proteomes UniProt
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available

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Representative proteomes UniProt

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We make all of our alignments available in Stockholm format. You can download them here as raw, plain text files or as gzip-compressed files.

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

HMM logo

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.

Note: You can also download the data file for the tree.

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.

Curation View help on the curation process

Seed source: Bateman A
Previous IDs: none
Type: Family
Sequence Ontology: SO:0100021
Author: Bateman A
Number in seed: 126
Number in full: 12890
Average length of the domain: 64.1 aa
Average identity of full alignment: 30 %
Average coverage of the sequence by the domain: 7.7 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 26.2 26.2
Trusted cut-off 26.2 26.2
Noise cut-off 26.1 26.1
Model length: 65
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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This visualisation provides a simple graphical representation of the distribution of this family across species. You can find the original interactive tree in the adjacent tab. More...

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The tree shows the occurrence of this domain across different species. More...


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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 HRM domain has been found. There are 138 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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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
A0A044R2Y8 View 3D Structure Click here
A0A044TQN4 View 3D Structure Click here
A0A044V9E0 View 3D Structure Click here
A0A077YZW4 View 3D Structure Click here
A0A077ZAG0 View 3D Structure Click here
A0A077ZGD6 View 3D Structure Click here
A0A0G2L5R5 View 3D Structure Click here
A0A0K0DW63 View 3D Structure Click here
A0A0K0E379 View 3D Structure Click here
A0A0K0EGZ6 View 3D Structure Click here
A0A0K0ESQ2 View 3D Structure Click here
A0A0N4UA76 View 3D Structure Click here
A0A0N4UHR7 View 3D Structure Click here
A0A0R4IKR9 View 3D Structure Click here
A0A158Q315 View 3D Structure Click here
A0A158Q3L3 View 3D Structure Click here
A0A1P6BTF1 View 3D Structure Click here
A0A2R8Q3H9 View 3D Structure Click here
A0A2R8QM07 View 3D Structure Click here
A0A2R8QN46 View 3D Structure Click here
A0A3P7DXB3 View 3D Structure Click here
A0A3P7E588 View 3D Structure Click here
A0A3P7FGC7 View 3D Structure Click here
A0A3Q0KKW6 View 3D Structure Click here
A0A3Q0KSN3 View 3D Structure Click here
A0A5K4F7L3 View 3D Structure Click here
A0A5S6PF64 View 3D Structure Click here
A0A5S6PFF2 View 3D Structure Click here
A0A5S6PGZ8 View 3D Structure Click here
A0A5S6PHA8 View 3D Structure Click here
A1Z9Q8 View 3D Structure Click here
A6QP74 View 3D Structure Click here
A8WG03 View 3D Structure Click here
A9Y366 View 3D Structure Click here
B0S4Y6 View 3D Structure Click here
C0HL12 View 3D Structure Click here
D4A831 View 3D Structure Click here
E2QCM9 View 3D Structure Click here
E7F0W8 View 3D Structure Click here
E7F1D8 View 3D Structure Click here