FGL1

Fibrinogen-like protein 1 (FGL-1) is a protein that is structurally related to fibrinogen. In humans, FGL-1 is encoded by the FGL1 gene.^[5][6] It is classified as a hepatokine. Four splice variants exist for this gene.

FGL1
Identifiers
Aliases	FGL1, HFREP1, HP-041, LFIRE-1, LFIRE1, fibrinogen like 1, HPS
External IDs	OMIM: 605776; MGI: 102795; HomoloGene: 37927; GeneCards: FGL1; OMA:FGL1 - orthologs
Gene location (Human) Chr. Chromosome 8 (human)[1] Band 8p22 Start 17,864,380 bp[1] End 17,910,365 bp[1]
Gene location (Mouse) Chr. Chromosome 8 (mouse)[2] Band 8|8 A4 Start 41,644,471 bp[2] End 41,668,193 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right lobe of liver body of pancreas sperm islet of Langerhans buccal mucosa cell testicle pancreatic epithelial cell endometrium placenta left testis Top expressed in left lobe of liver sexually immature organism motor neuron primary oocyte right kidney proximal tubule secondary oocyte primitive streak Paneth cell supraoptic nucleus More reference expression data BioGPS More reference expression data
Orthologs Species Human Mouse Entrez 2267 234199 Ensembl ENSG00000104760 ENSMUSG00000031594 UniProt Q08830 Q71KU9 RefSeq (mRNA) NM_201553 NM_004467 NM_147203 NM_201552 NM_145594 RefSeq (protein) NP_004458 NP_671736 NP_963846 NP_963847 NP_663569 Location (UCSC) Chr 8: 17.86 – 17.91 Mb Chr 8: 41.64 – 41.67 Mb PubMed search [3] [4]
Wikidata
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Function

Fibrinogen-like protein 1 is a member of the fibrinogen family of proteins, which also includes fibrinogen, fibrinogen-like protein 2, and clotting factors V, VIII, and XIII. FGL-1 is homologous to the carboxy terminus of the fibrinogen beta- and gamma- subunits which contains the four conserved cysteines of that are common to all members of the fibrinogen family. However, FGL-1 lacks the platelet-binding site, cross-linking region, and thrombin-sensitive site which allow the other members of the fibrinogen family to aid in fibrin clot formation.^[6]

FGL-1 has also been observed to strongly bind to and activate LAG-3, a regulatory protein expressed on T cells. As LAG-3 has an important role in controlling activated T cells, manipulating FGL-1 binding to T cells has been proposed for both cancer immunotherapy and anti-inflammatory treatments.^[7]

Clinical significance

FGL-1 may play a role in the development of hepatocellular carcinomas.^[6]