Summary: Apoptosis preventing protein
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.
Apoptosis preventing protein Provide feedback
This viral protein functions to block the host apoptotic response caused by infection by the virus. The apoptosis preventing protein (or early 35kD protein, P35) acts by blocking caspase protease activity.
Literature references
-
Fisher AJ, Cruz Wd, Zoog SJ, Schneider CL, Friesen PD; , EMBO J 1999;18:2031-2039.: Crystal structure of baculovirus P35: role of a novel reactive site loop in apoptotic caspase inhibition. PUBMED:10205157 EPMC:10205157
External database links
| PANDIT: | PF02331 |
| Pseudofam: | PF02331 |
| SCOP: | 1p35 |
| SYSTERS: | P35 |
This tab holds annotation information from the InterPro database.
InterPro entry IPR003429
Peptide proteinase inhibitors can be found as single domain proteins or as single or multiple domains within proteins; these are referred to as either simple or compound inhibitors, respectively. In many cases they are synthesised as part of a larger precursor protein, either as a prepropeptide or as an N-terminal domain associated with an inactive peptidase or zymogen. This domain prevents access of the substrate to the active site. Removal of the N-terminal inhibitor domain either by interaction with a second peptidase or by autocatalytic cleavage activates the zymogen. Other inhibitors interact direct with proteinases using a simple noncovalent lock and key mechanism; while yet others use a conformational change-based trapping mechanism that depends on their structural and thermodynamic properties.
The anti-apoptotic protein p35 from baculovirus is thought to prevent the suicidal response of infected insect cells by inhibiting caspases. Ectopic expression of p35 in a number of transgenic animals or cell lines is also anti-apoptotic, giving rise to the hypothesis that the protein is a general inhibitor of caspases.
This protein belongs to MEROPS proteinase inhibitor family I50, clan IQ. Purified recombinant p35 inhibits human caspase-1, -3, -6, -7, -8, and -10 but does not significantly inhibit unrelated serine or cysteine proteases, implying that p35 is a potent caspase-specific inhibitor. The interaction of p35 with caspase-3, as a model of the inhibitory mechanism,revealed classic slow-binding inhibition, with both active-sites of the caspase-3 dimer acting equally and independently. Inhibition resulted from complex formation between the enzyme and inhibitor, which could be visualised under non-denaturing conditions, but was dissociated by SDS to give p35 cleaved at Asp87, the P1 residue of the inhibitor. Complex formation requires the substrate-binding cleft to be unoccupied [PUBMED:9692966].
Infecting the insect cell line IPLB-Ld652Y with the baculovirus Autographa californica nuclear polyhedrosis virus (AcMNPV) results in global translation arrest, which correlates with the presence of the AcMNPV apoptotic suppressor, p35. However, the anti-apoptotic function of p35 in translation arrest is not solely due to caspase inactivation, but its activity enhances signalling to a separate translation arrest pathway, possibly by stimulating the late stages of the baculovirus infection cycle [PUBMED:14980489].
Gene Ontology
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
| Molecular function | cysteine-type endopeptidase inhibitor activity involved in apoptotic process (GO:0043027) |
| Biological process | anti-apoptosis (GO:0006916) |
Domain organisation
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
Loading domain graphics...
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 (7) |
Full (25) |
Representative proteomes | NCBI (29) |
Meta (0) |
||||
|---|---|---|---|---|---|---|---|---|
| RP15 (0) |
RP35 (0) |
RP55 (0) |
RP75 (0) |
|||||
| Jalview | ||||||||
| HTML | ||||||||
| PP/heatmap | 1 | |||||||
| Pfam viewer | ||||||||
1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key:
available,
not generated,
— not available.
Format an alignment
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 (7) |
Full (25) |
Representative proteomes | NCBI (29) |
Meta (0) |
||||
|---|---|---|---|---|---|---|---|---|
| RP15 (0) |
RP35 (0) |
RP55 (0) |
RP75 (0) |
|||||
| Raw Stockholm | ||||||||
| Gzipped | ||||||||
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
| Seed source: | Pfam-B_13247 (release 5.2) |
| Previous IDs: | none |
| Type: | Domain |
| Author: | Mian N, Bateman A |
| Number in seed: | 7 |
| Number in full: | 25 |
| Average length of the domain: | 301.10 aa |
| Average identity of full alignment: | 58 % |
| Average coverage of the sequence by the domain: | 92.61 % |
HMM information
| HMM build commands: |
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 23193494 -E 1000 --cpu 4 HMM pfamseq
|
||||||||||||
| Model details: |
|
||||||||||||
| Model length: | 301 | ||||||||||||
| Family (HMM) version: | 10 | ||||||||||||
| Download: | download the raw HMM for this family |
Species distribution
Sunburst controls
ShowThis 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...
Tree controls
HideThe 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 P35 domain has been found. There are 10 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...

Archea
Eukaryota
Bacteria
Other sequences
Viruses
Unclassified
Viroids
Unclassified sequence