Summary: Inhibitor of Apoptosis domain
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Inhibitor of apoptosis domain Edit Wikipedia article
|Inhibitor of Apoptosis domain|
The inhibitor of apoptosis domain -- also known as IAP repeat, Baculovirus Inhibitor of apoptosis protein Repeat, or BIR -- is a structural motif found in proteins with roles in apoptosis, cytokine production, and chromosome segregation. Proteins containing BIR are known as inhibitor of apoptosis proteins (IAPs), or BIR-containing proteins (BIRPs or BIRCs), and include BIRC1 (NAIP), BIRC2 (cIAP1), BIRC3 (cIAP2), BIRC4 (xIAP), BIRC5 (survivin) and BIRC6.
BIR domains belong to the zinc-finger domain family and characteristically have a number of invariant amino acid residues, including 3 conserved cysteines and one conserved histidine, which coordinate a zinc ion. They are typically composed of 4-5 alpha helices and a three-stranded beta sheet.
- Eukaryotic Linear Motif resource motif class LIG_BIR_II_1
- Eukaryotic Linear Motif resource motif class LIG_BIR_III_1
- Eukaryotic Linear Motif resource motif class LIG_BIR_III_2
- Eukaryotic Linear Motif resource motif class LIG_BIR_III_3
- Eukaryotic Linear Motif resource motif class LIG_BIR_III_4
- doi:10.1038/10701. PMID 10404221.;Hinds MG, Norton RS, Vaux DL, Day CL (July 1999). "Solution structure of a baculoviral inhibitor of apoptosis (IAP) repeat". Nat. Struct. Biol. 6 (7): 648–51.
- Silke J, Vaux DL (May 2001). "Two kinds of BIR-containing protein - inhibitors of apoptosis, or required for mitosis". J. Cell Sci. 114 (Pt 10): 1821–7. PMID 11329368.
- Verhagen AM, Coulson EJ, Vaux DL (2001). "Inhibitor of apoptosis proteins and their relatives: IAPs and other BIRPs". Genome Biol. 2 (7): REVIEWS3009. doi:10.1186/gb-2001-2-7-reviews3009. PMC . PMID 11516343.
- Birnbaum MJ, Clem RJ, Miller LK (April 1994). "An apoptosis-inhibiting gene from a nuclear polyhedrosis virus encoding a polypeptide with Cys/His sequence motifs". J. Virol. 68 (4): 2521–8. PMC . PMID 8139034.
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Inhibitor of Apoptosis domain Provide feedback
BIR stands for 'Baculovirus Inhibitor of apoptosis protein Repeat'. It is found repeated in inhibitor of apoptosis proteins (IAPs), and in fact it is also known as IAP repeat. These domains characteristically have a number of invariant residues, including 3 conserved cysteines and one conserved histidine that coordinate a zinc ion. They are usually made up of 4-5 alpha helices and a three-stranded beta-sheet. BIR is also found in other proteins known as BIR-domain-containing proteins (BIRPs), such as Survivin (O15392) .
Birnbaum MJ, Clem RJ, Miller LK; , J Virol 1994;68:2521-2528.: An apoptosis-inhibiting gene from a nuclear polyhedrosis virus encoding a polypeptide with Cys/His sequence motifs. PUBMED:8139034 EPMC:8139034
Internal database links
|Similarity to PfamA using HHSearch:||zf-C3HC|
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR001370
The 'baculovirus inhibitior of apoptosis protein repeat' (BIR) [ PUBMED:8139034 , PUBMED:8552191 ] is a domain of about 70 residues arranged in tandem repeats separated by a variable length linker, that seems to confer cell death-preventing activity. It is found in proteins belonging to the IAP (inhibitor of apoptosis proteins) family. The critical motifs required for anti-apoptotic activity of IAP proteins are the BIRs. All IAP proteins contain from one to three BIRs, and all known interactions between IAPs and other proteins are mediated by one or more BIRs [ PUBMED:10404221 ]. In higher eukaryotes, BIR domains inhibit apoptosis by acting as direct inhibitors of the caspase family of protease enzymes. Proteins with BIR domains are considered peptidase inhibitors in family I32. In yeast, BIR domains are involved in regulating cytokinesis. This novel fold is stabilized by zinc tetrahedrally coordinated by one histidine and three cysteine residues and resembles a classical zinc finger [ PUBMED:8445726 ].
The BIR domain has a fold that is stabilised by zinc tetrahedrally coordinated by one histidine and three cysteine residues. The structure consists of three short alpha-helices and turns with the zinc packed in an unusually hydrophobic environment created by residues that are highly conserved among all BIRs. A subclass of repeats, comprising those at the C terminus of a series of BIR repeats from IAP proteins bearing RING finger domains, are likely to contain a C-terminal region that form an alpha-helix [ PUBMED:10404221 ].
Proteins that are known to contain this domain include:
- Baculoviruses apoptosis inhibitors (IAPs).
- Mammalian apoptosis inhibitors 1 and 2 (IAP1 and IAP2; BIRC-2 and BIRC-3; MEROPS identifiers I32.002 and I32.003, respectively).
- Mammalian X-linked inhibitor of apoptosis protein (X-linked IAP; MEROPS identifier I32.004).
- Chicken IAP (ITA).
- Human neuronal apoptosis inhibitory protein (NAIP, BIRC-1; MEROPS identifier I32.001).
- Drosophila apoptosis inhibitors 1 and 2 (Iap1 and Iap2; MEROPS identifiers I32.009 and I32.011, respectively)).
- African Swine Fever Virus (ASFV) protein p27.
Below is a listing of the unique domain organisations or architectures in which this domain is found. More...
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|Number in seed:||71|
|Number in full:||6995|
|Average length of the domain:||69.10 aa|
|Average identity of full alignment:||38 %|
|Average coverage of the sequence by the domain:||12.37 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 57096847 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||23|
|Download:||download the raw HMM for this family|
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For all of the domain matches in a full alignment, we count the number that are found on all sequences in the alignment. This total is shown in the purple box.
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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 BIR domain has been found. There are 312 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.