Please note: this site relies heavily on the use of javascript. Without a javascript-enabled browser, this site will not function correctly. Please enable javascript and reload the page, or switch to a different browser.
24  structures 380  species 0  interactions 2816  sequences 31  architectures

Family: Snf7 (PF03357)

Summary: Snf7

Pfam includes annotations and additional family information from a range of different sources. These sources can be accessed via the tabs below.

The Pfam group coordinates the annotation of Pfam families in Wikipedia, but we have not yet assigned a Wikipedia article to this family. If you think that a particular Wikipedia article provides good annotation, please let us know.

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.

Snf7 Provide feedback

This family of proteins are involved in protein sorting and transport from the endosome to the vacuole/lysosome in eukaryotic cells. Vacuoles/lysosomes play an important role in the degradation of both lipids and cellular proteins. In order to perform this degradative function, vacuoles/lysosomes contain numerous hydrolases which have been transported in the form of inactive precursors via the biosynthetic pathway and are proteolytically activated upon delivery to the vacuole/lysosome. The delivery of transmembrane proteins, such as activated cell surface receptors to the lumen of the vacuole/lysosome, either for degradation/downregulation, or in the case of hydrolases, for proper localisation, requires the formation of multivesicular bodies (MVBs). These late endosomal structures are formed by invaginating and budding of the limiting membrane into the lumen of the compartment. During this process, a subset of the endosomal membrane proteins is sorted into the forming vesicles. Mature MVBs fuse with the vacuole/lysosome, thereby releasing cargo containing vesicles into its hydrolytic lumen for degradation. Endosomal proteins that are not sorted into the intralumenal MVB vesicles are either recycled back to the plasma membrane or Golgi complex, or remain in the limiting membrane of the MVB and are thereby transported to the limiting membrane of the vacuole/lysosome as a consequence of fusion. Therefore, the MVB sorting pathway plays a critical role in the decision between recycling and degradation of membrane proteins [1]. A few archaeal sequences are also present within this family.

Literature references

  1. Babst M, Katzmann DJ, Estepa-Sabal EJ, Meerloo T, Emr SD; , Dev Cell 2002;3:271-282.: Escrt-III: an endosome-associated heterooligomeric protein complex required for mvb sorting. PUBMED:12194857 EPMC:12194857

  2. Teo H, Perisic O, Gonzalez B, Williams RL; , Dev Cell 2004;7:559-569.: ESCRT-II, an endosome-associated complex required for protein sorting: crystal structure and interactions with ESCRT-III and membranes. PUBMED:15469844 EPMC:15469844

  3. Peck JW, Bowden ET, Burbelo PD; , Biochem J 2004;377:693-700.: Structure and function of human Vps20 and Snf7 proteins. PUBMED:14583093 EPMC:14583093


External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR005024

This is a family of eukaryotic proteins which are variously described as either hypothetical protein, developmental protein or related to yeast SNF7. The family contains human CHMP1. CHMP1 (CHromatin Modifying Protein; CHarged Multivesicular body Protein), is encoded by an alternative open reading frame in the PRSM1 gene [PUBMED:8863740] and is conserved in both complex and simple eukaryotes. CHMP1 contains a predicted bipartite nuclear localisation signal and distributes as distinct forms to the cytoplasm and the nuclear matrix in all cell lines tested.

Human CHMP1 is strongly implicated in multivesicular body formation. A multivesicular body is a vesicle-filled endosome that targets proteins to the interior of lysosomes. Immunocytochemistry and biochemical fractionation localise CHMP1 to early endosomes and CHMP1 physically interacts with SKD1/VPS4, a highly conserved protein directly linked to multivesicular body sorting in yeast. Similar to the action of a mutant SKD1 protein, over expression of a fusion derivative of human CHMP1 dilates endosomal compartments and disrupts the normal distribution of several endosomal markers. Genetic studies in Saccharomyces cerevisiae (Baker's yeast) further support a conserved role of CHMP1 in vesicle trafficking. Deletion of CHM1, the budding yeast homologue of CHMP1, results in defective sorting of carboxypeptidases S and Y and produces abnormal, multi-lamellar prevacuolar compartments. This phenotype classifies CHM1 as a member of the class E vacuolar protein sorting genes [PUBMED:11559747].

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...

Loading domain graphics...

Pfam Clan

This family is a member of clan PspA (CL0235), which has the following description:

This clan includes PspA like proteins that are transcriptional activators as well as Snf7, a protein involved in cellular trafficking.

The clan contains the following 2 members:

PspA_IM30 Snf7

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
(34)
Full
(2816)
Representative proteomes NCBI
(2693)
Meta
(44)
RP15
(636)
RP35
(1020)
RP55
(1514)
RP75
(1871)
Jalview View  View  View  View  View  View  View  View 
HTML View  View  View  View  View  View     
PP/heatmap 1 View  View  View  View  View     
Pfam viewer View  View             

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

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

Format an alignment

  Seed
(34)
Full
(2816)
Representative proteomes NCBI
(2693)
Meta
(44)
RP15
(636)
RP35
(1020)
RP55
(1514)
RP75
(1871)
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
(34)
Full
(2816)
Representative proteomes NCBI
(2693)
Meta
(44)
RP15
(636)
RP35
(1020)
RP55
(1514)
RP75
(1871)
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: Pfam-B_1641 (release 6.6)
Previous IDs: DUF279; SNF7; ESCRT-III;
Type: Family
Author: Mifsud W, Moxon SJ, Mistry J, Wood V
Number in seed: 34
Number in full: 2816
Average length of the domain: 169.10 aa
Average identity of full alignment: 19 %
Average coverage of the sequence by the domain: 70.47 %

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 21.9 21.9
Trusted cut-off 21.9 21.9
Noise cut-off 21.8 21.8
Model length: 171
Family (HMM) version: 16
Download: download the raw HMM for this family

Species distribution

Sunburst controls

Show

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...

Loading sunburst data...

Tree controls

Hide

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

Loading...

Please note: for large trees this can take some time. While the tree is loading, you can safely switch away from this tab but if you browse away from the family page entirely, the tree will not be loaded.

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 Snf7 domain has been found. There are 24 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.

Loading structure mapping...