Perforin

Not to be confused with Porphyrin.

Perforin 1 (pore forming protein)
250px The structure of a MACPF domain containing protein Plu-MACPF: PDB: 2QP2​ The MACPF domain is in cyan/pink. Another domain, the ? prism domain is in orange. Two calcium atoms are in grey.
Identifiers
Symbols	PRF1 ; FLH2; HPLH2; P1; PFN1; PFP
External IDs	OMIM: 170280 MGI: 97551 HomoloGene: 3698 ChEMBL: 5480 GeneCards: PRF1 Gene
Gene ontology Molecular function • calcium ion binding • protein binding • wide pore channel activity Cellular component • extracellular space • plasma membrane • membrane • integral component of membrane • cytoplasmic membrane-bounded vesicle • endosome lumen • cytolytic granule Biological process • immunological synapse formation • defense response to tumor cell • immune response to tumor cell • apoptotic process • cellular defense response • circadian rhythm • cytolysis • response to ethanol • protein homooligomerization • defense response to virus • transmembrane transport Sources: Amigo / QuickGO
RNA expression pattern
File:PBB GE PRF1 214617 at tn.png
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	5551	18646
Ensembl	ENSG00000180644	ENSMUSG00000037202
UniProt	P14222	P10820
RefSeq (mRNA)	NM_001083116	NM_011073
RefSeq (protein)	NP_001076585	NP_035203
Location (UCSC)	Chr 10: 70.6 – 70.6 Mb	Chr 10: 61.3 – 61.3 Mb
PubMed search	[1]	[2]

Perforin-1 is a protein that in humans is encoded by the PRF1 gene and the Prf1 gene in mice.

Function

Perforin is a pore forming cytolytic protein found in the granules of Cytotoxic T lymphocytes (CTLs) and NK cells. Upon degranulation, perforin binds to the target cell's plasma membrane, and oligomerises in a Ca2+ dependent manner to form pores on the target cell. The pore formed allows for the passive diffusion of a family of pro-apoptotic proteases, known as the granzymes in to the target cell. The lytic membrane-inserting part of perforin is the MACPF domain. This region shares homology with cholesterol-dependent cytolysins from Gram-positive bacteria.

Perforin has structural and functional similarities to complement component 9 (C9). Like C9, this protein creates transmembrane tubules and is capable of lysing non-specifically a variety of target cells. This protein is one of the main cytolytic proteins of cytolytic granules, and it is known to be a key effector molecule for T-cell- and natural killer-cell-mediated cytolysis. Perforin is thought to act by creating holes in the plasma membrane which triggers an influx of calcium and initiates membrane repair mechanisms. These repair mechanisms bring perforin and granzymes into early endosomes.

Clinical significance

Homozygous inheritance of defective PRF1 alleles result in the development of familial hemophagocytic lymphohistiocytosis type 2 (FHL2), a rare and lethal autosomal recessive disorder of infancy.

Interactions

Perforin has been shown to interact with calreticulin.

See also

• Granzymes
• Defensin

External links

• perforin at the US National Library of Medicine Medical Subject Headings (MeSH)

Perforin at NLM Genetics Home Reference