FCN1

Protein identityUniProt · HPA

UniProt accession

O00602

Gene

FCN1

Ensembl

ENSG00000085265

Chromosome

9

Canonical length

326 aa

Protein class

Plasma proteins, Predicted secreted proteins

Secretome location

Secreted to blood

Quaternary structure

Homotrimer

OverviewNCBI Gene

The ficolin family of proteins are characterized by the presence of a leader peptide, a short N-terminal segment, followed by a collagen-like region, and a C-terminal fibrinogen-like domain. The collagen-like and the fibrinogen-like domains are also found separately in other proteins such as complement protein C1q, C-type lectins known as collectins, and tenascins. However, all these proteins recognize different targets, and are functionally distinct. Ficolin 1 encoded by FCN1 is predominantly expressed in the peripheral blood leukocytes, and has been postulated to function as a plasma protein with elastin-binding activity. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

326 residues, UniProt reviewed canonical sequence.

>O00602|FCN1
     1  MELSGATMAR GLAVLLVLFL HIKNLPAQAA DTCPEVKVVG LEGSDKLTIL RGCPGLPGAP
    61  GPKGEAGVIG ERGERGLPGA PGKAGPVGPK GDRGEKGMRG EKGDAGQSQS CATGPRNCKD
   121  LLDRGYFLSG WHTIYLPDCR PLTVLCDMDT DGGGWTVFQR RMDGSVDFYR DWAAYKQGFG
   181  SQLGEFWLGN DNIHALTAQG SSELRVDLVD FEGNHQFAKY KSFKVADEAE KYKLVLGAFV
   241  GGSAGNSLTG HNNNFFSTKD QDNDVSSSNC AEKFQGAWWY ADCHASNLNG LYLMGPHESY
   301  ANGINWSAAK GYKYSYKVSE MKVRPA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FCN1 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

Cell surface

Secreted

No

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.38

Highest tissue expression

150 nTPM

Expression across tissuesHPA

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)

1.82

gnomAD pLI

0

gnomAD missense Z

-0.29

DepMap mean gene effect

0.07

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

• cell surface pattern recognition receptor signaling pathway
• complement activation, lectin pathway
• G protein-coupled receptor signaling pathway
• host-mediated suppression of symbiont invasion
• positive regulation of interleukin-8 production
• positive regulation of opsonization
• protein localization to cell surface
• proteolysis
• recognition of apoptotic cell

Molecular functions

• antigen binding
• carbohydrate binding
• carbohydrate derivative binding
• G protein-coupled receptor binding
• metal ion binding
• pattern recognition receptor activity
• sialic acid binding
• signaling receptor binding

Cellular components

• collagen trimer
• external side of plasma membrane
• extracellular matrix
• extracellular region
• extracellular space
• ficolin-1-rich granule lumen
• plasma membrane
• secretory granule lumen
• serine-type endopeptidase complex
• symbiont cell surface

Protein domainsUniProt · Pfam · InterPro

• Fibrinogen, alpha/beta/gamma chain, C-terminal globular domain
• Collagen triple helix repeat
• Fibrinogen, alpha/beta/gamma chain, C-terminal globular, subdomain 1
• Fibrinogen, conserved site
• Fibrinogen-like, C-terminal
• Fibrinogen C-terminal domain-containing protein
• Fibrinogen beta and gamma chains, C-terminal globular domain
• Collagen triple helix repeat (20 copies)

KeywordsUniProt

• Calcium
• Collagen
• Disulfide bond
• Glycoprotein
• Immunity
• Innate immunity
• Lectin
• Metal-binding
• Repeat
• Secreted
• Signal

InteractionsUniProt · HPA

Protein binding partners of FCN1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

• CRP
• FFAR2