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178  structures 4016  species 1  interaction 9881  sequences 34  architectures

Family: HSP20 (PF00011)

Summary: Hsp20/alpha crystallin family

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This is the Wikipedia entry entitled "Hsp20". More...

Hsp20 Edit Wikipedia article

Hsp20/alpha crystallin family
Identifiers
Symbol HSP20
Pfam PF00011
InterPro IPR002068
PROSITE PDOC00791
SCOP 1shs
SUPERFAMILY 1shs

Heat shock protein Hsp20 is a family of heat shock proteins.

Prokaryotic and eukaryotic organisms respond to heat shock or other environmental stress by inducing the synthesis of proteins collectively known as heat-shock proteins (hsp).[1] Amongst them is a family of proteins with an average molecular weight of 20 Kd, known as the hsp20 proteins.[2] These seem to act as protein chaperones that can protect other proteins against heat-induced denaturation and aggregation. Hsp20 proteins seem to form large heterooligomeric aggregates. Structurally, this family is characterised by the presence of a conserved C-terminal domain, alpha-crystallin domain, of about 100 residues. Recently, small heat shock proteins (sHSPs) were found in marine viruses (cyanophages).[3]

Human proteins containing this domain

CRYAA; CRYAB; HSPB1; HSPB2; HSPB3; HSPB6; HSPB7; HSPB8; HSPB9;

References

  1. ^ Lindquist S, Craig EA (1988). "The heat-shock proteins". Annu. Rev. Genet. 22: 631–677. doi:10.1146/annurev.ge.22.120188.003215. PMID 2853609. 
  2. ^ Merck KB, de Jong WW, Bloemendal H, Groenen PJ (1994). "Structure and modifications of the junior chaperone alpha-crystallin. From lens transparency to molecular pathology". Eur. J. Biochem. 225 (1): 1–9. doi:10.1111/j.1432-1033.1994.00001.x. PMID 7925426. 
  3. ^ Maaroufi H, Tanguay RM (2013). "Analysis and phylogeny of small heat shock proteins from marine viruses and their cyanobacteria host.". PLoS ONE 8 (11): e81207. doi:10.1371/journal.pone.0081207. PMID 24265841. 

This article incorporates text from the public domain Pfam and InterPro IPR002068

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

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Hsp20/alpha crystallin family Provide feedback

No Pfam abstract.

Literature references

  1. Kim KK, Kim R, Kim SH , Nature 1998;394:595-599.: Crystal structure of a small heat-shock protein. PUBMED:9707123 EPMC:9707123


External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR002068

Prokaryotic and eukaryotic organisms respond to heat shock or other environmental stress by inducing the synthesis of proteins collectively known as heat-shock proteins (hsp) [PUBMED:2853609]. Amongst them is a family of proteins with an average molecular weight of 20 Kd, known as the hsp20 proteins [PUBMED:7925426]. These seem to act as chaperones that can protect other proteins against heat-induced denaturation and aggregation. Hsp20 proteins seem to form large heterooligomeric aggregates. Structurally, this family is characterised by the presence of a conserved C-terminal domain of about 100 residues.

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 HSP20 (CL0190), which has the following description:

The small heat shock proteins (sHSPs) prevent protein aggregation during heat shock and oppose regulated cell death. A conserved arginine residue in the HSP20/alpha-crystallin domain (Pfam:PF00011) has in fact been implicated in the development of cataracts and myopathies [1]. The CS family (Pfam:PF04969) includes proteins that are known to bind HSP90 [2], as well as p23 (Swiss:Q15185), which is an HSP90 co-chaperone [3].

The clan contains the following 4 members:

CS GvpH HSP20 PIH1

Alignments

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 using the family HMM. We also generate alignments using four representative proteomes (RP) sets, the NCBI sequence database, and our metagenomics sequence database. More...

View options

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.

  Seed
(37)
Full
(9881)
Representative proteomes NCBI
(8031)
Meta
(3065)
RP15
(1108)
RP35
(2207)
RP55
(2972)
RP75
(3585)
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available

Key: ✓ available, x not generated, not available.

Format an alignment

  Seed
(37)
Full
(9881)
Representative proteomes NCBI
(8031)
Meta
(3065)
RP15
(1108)
RP35
(2207)
RP55
(2972)
RP75
(3585)
Alignment:
Format:
Order:
Sequence:
Gaps:
Download/view:

Download options

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.

  Seed
(37)
Full
(9881)
Representative proteomes NCBI
(8031)
Meta
(3065)
RP15
(1108)
RP35
(2207)
RP55
(2972)
RP75
(3585)
Raw Stockholm Download   Download   Download   Download   Download   Download   Download   Download  
Gzipped Download   Download   Download   Download   Download   Download   Download   Download  

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

External links

MyHits provides a collection of tools to handle multiple sequence alignments. For example, one can refine a seed alignment (sequence addition or removal, re-alignment or manual edition) and then search databases for remote homologs using HMMER3.

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...

Trees

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: Prosite
Previous IDs: none
Type: Family
Author: Sonnhammer ELL
Number in seed: 37
Number in full: 9881
Average length of the domain: 97.10 aa
Average identity of full alignment: 23 %
Average coverage of the sequence by the domain: 59.55 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 20.8 20.8
Trusted cut-off 20.8 20.8
Noise cut-off 20.7 20.7
Model length: 102
Family (HMM) version: 16
Download: download the raw HMM for this family

Species distribution

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Interactions

There is 1 interaction for this family. More...

HSP20

Structures

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 HSP20 domain has been found. There are 178 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 seqence.

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