CFP

Protein identityUniProt · HPA

UniProt accession

P27918

Gene

CFP

Ensembl

ENSG00000126759

Chromosome

X

Canonical length

469 aa

Protein class

Disease related genes, Human disease related genes, Plasma proteins, Predicted intracellular proteins, Predicted secreted proteins

Subcellular location

Vesicles

Secretome location

Secreted to blood

OverviewNCBI Gene

This gene encodes a plasma glycoprotein that positively regulates the alternative complement pathway of the innate immune system. This protein binds to many microbial surfaces and apoptotic cells and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that ultimately leads to formation of the membrane attack complex and lysis of the target cell. Mutations in this gene result in two forms of properdin deficiency, which results in high susceptibility to meningococcal infections. Multiple alternatively spliced variants, encoding the same protein, have been identified.[provided by RefSeq, Feb 2009]

Canonical amino-acid sequenceUniProt

469 residues, UniProt reviewed canonical sequence.

>P27918|CFP
     1  MITEGAQAPR LLLPPLLLLL TLPATGSDPV LCFTQYEESS GKCKGLLGGG VSVEDCCLNT
    61  AFAYQKRSGG LCQPCRSPRW SLWSTWAPCS VTCSEGSQLR YRRCVGWNGQ CSGKVAPGTL
   121  EWQLQACEDQ QCCPEMGGWS GWGPWEPCSV TCSKGTRTRR RACNHPAPKC GGHCPGQAQE
   181  SEACDTQQVC PTHGAWATWG PWTPCSASCH GGPHEPKETR SRKCSAPEPS QKPPGKPCPG
   241  LAYEQRRCTG LPPCPVAGGW GPWGPVSPCP VTCGLGQTME QRTCNHPVPQ HGGPFCAGDA
   301  TRTHICNTAV PCPVDGEWDS WGEWSPCIRR NMKSISCQEI PGQQSRGRTC RGRKFDGHRC
   361  AGQQQDIRHC YSIQHCPLKG SWSEWSTWGL CMPPCGPNPT RARQRLCTPL LPKYPPTVSM
   421  VEGQGEKNVT FWGRPLPRCE ELQGQKLVVE EKRPCLHVPA CKDPEEEEL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CFP can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability

Secreted

Secreted

Yes

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.39

Highest tissue expression

79 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about CFP.

Disease | AllUniProt

Conditions CFP is implicated in, by any mechanism.

• Properdin deficiency (PFD) MIM:312060

Disease | GeneticClinVar

8 pathogenic / likely-pathogenic of 264 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Properdin deficiency, X-linked
• Properdin deficiency, type III

ReferencesPubMed · IEDB

Publications for CFP from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)

0.43

gnomAD pLI

0.69

gnomAD missense Z

2.17

DepMap mean gene effect

0.05

DepMap dependency class

none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

• complement activation
• complement activation, alternative pathway
• defense response to bacterium
• immune response
• positive regulation of immune response
• positive regulation of opsonization
• protein stabilization
• positive regulation of complement activation, alternative pathway

Cellular components

• cytoplasmic side of Golgi membrane
• endoplasmic reticulum lumen
• extracellular region
• extracellular space
• specific granule lumen
• tertiary granule lumen

Protein domainsUniProt · Pfam · InterPro

• Thrombospondin type-1 (TSP1) repeat
• Thrombospondin type-1 repeat superfamily
• Thrombospondin type 1 domain
• Properdin, thrombospondin type 1 repeat 0
• Complement and asymmetry regulator
• Properdin, thrombospondin type 1 C-terminal
• Thrombospondin type 1 repeat
• CFP-like, C-terminal thrombospondin type 1 domain

KeywordsUniProt

• Complement alternate pathway
• Disulfide bond
• Glycoprotein
• Immunity
• Innate immunity
• Repeat
• Secreted
• Signal

InteractionsUniProt · HPA

Protein binding partners of CFP in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• CFB
• C3