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    CFI complement factor I [ Homo sapiens (human) ]

    Gene ID: 3426, updated on 9-Dec-2024

    Summary

    Official Symbol
    CFIprovided by HGNC
    Official Full Name
    complement factor Iprovided by HGNC
    Primary source
    HGNC:HGNC:5394
    See related
    Ensembl:ENSG00000205403 MIM:217030; AllianceGenome:HGNC:5394
    Gene type
    protein coding
    RefSeq status
    REVIEWED
    Organism
    Homo sapiens
    Lineage
    Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
    Also known as
    FI; IF; KAF; AHUS3; ARMD13; C3BINA; C3b-INA
    Summary
    This gene encodes a serine proteinase that is essential for regulating the complement cascade. The encoded preproprotein is cleaved to produce both heavy and light chains, which are linked by disulfide bonds to form a heterodimeric glycoprotein. This heterodimer can cleave and inactivate the complement components C4b and C3b, and it prevents the assembly of the C3 and C5 convertase enzymes. Defects in this gene cause complement factor I deficiency, an autosomal recessive disease associated with a susceptibility to pyogenic infections. Mutations in this gene have been associated with a predisposition to atypical hemolytic uremic syndrome, a disease characterized by acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. Primary glomerulonephritis with immune deposits and age-related macular degeneration are other conditions associated with mutations of this gene. [provided by RefSeq, Dec 2015]
    Expression
    Biased expression in liver (RPKM 171.8), kidney (RPKM 63.6) and 9 other tissues See more
    Orthologs
    NEW
    Try the new Gene table
    Try the new Transcript table

    Genomic context

    See CFI in Genome Data Viewer
    Location:
    4q25
    Exon count:
    16
    Annotation release Status Assembly Chr Location
    RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 4 NC_000004.12 (109730982..109801999, complement)
    RS_2024_08 current T2T-CHM13v2.0 (GCF_009914755.1) 4 NC_060928.1 (113031939..113104052, complement)
    RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 4 NC_000004.11 (110652138..110723155, complement)

    Chromosome 4 - NC_000004.12Genomic Context describing neighboring genes Neighboring gene mitochondrial calcium uniporter dominant negative subunit beta Neighboring gene HIG1 hypoxia inducible domain family member 1A pseudogene 14 Neighboring gene caspase 6 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 21804 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 21805 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 15624 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 15625 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 21806 Neighboring gene phospholipase A2 group XIIA Neighboring gene ATAC-STARR-seq lymphoblastoid active region 21807 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 15626 Neighboring gene H3K27ac hESC enhancer GRCh37_chr4:110651344-110652220 Neighboring gene uncharacterized LOC124900757 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 21808 Neighboring gene GAR1 divergent transcript

    Genomic regions, transcripts, and products

    Expression

    • Project title: HPA RNA-seq normal tissues
    • Description: RNA-seq was performed of tissue samples from 95 human individuals representing 27 different tissues in order to determine tissue-specificity of all protein-coding genes
    • BioProject: PRJEB4337
    • Publication: PMID 24309898
    • Analysis date: Wed Apr 4 07:08:55 2018

    Bibliography

    GeneRIFs: Gene References Into Functions

    What's a GeneRIF?

    Phenotypes

    Associated conditions

    Description Tests
    Age related macular degeneration 13
    MedGen: C3809523 OMIM: 615439 GeneReviews: Not available
    not available
    Atypical hemolytic-uremic syndrome with I factor anomaly not available
    Factor I deficiency
    MedGen: C3463916 OMIM: 610984 GeneReviews: C3 Glomerulopathy
    not available

    EBI GWAS Catalog

    Description
    Common variants near FRK/COL10A1 and VEGFA are associated with advanced age-related macular degeneration.
    EBI GWAS Catalog
    Genetic variants near TIMP3 and high-density lipoprotein-associated loci influence susceptibility to age-related macular degeneration.
    EBI GWAS Catalog
    Genome-wide association study of advanced age-related macular degeneration identifies a role of the hepatic lipase gene (LIPC).
    EBI GWAS Catalog
    Genome-wide contribution of genotype by environment interaction to variation of diabetes-related traits.
    EBI GWAS Catalog
    Heritability and genome-wide association study to assess genetic differences between advanced age-related macular degeneration subtypes.
    EBI GWAS Catalog
    Seven new loci associated with age-related macular degeneration.
    EBI GWAS Catalog

    Pathways from PubChem

    Interactions

    Products Interactant Other Gene Complex Source Pubs Description

    General gene information

    Markers

    Gene Ontology Provided by GOA

    Function Evidence Code Pubs
    enables metal ion binding IEA
    Inferred from Electronic Annotation
    more info
     
    enables protein binding IPI
    Inferred from Physical Interaction
    more info
    PubMed 
    enables serine-type endopeptidase activity IEA
    Inferred from Electronic Annotation
    more info
     
    Process Evidence Code Pubs
    involved_in complement activation, classical pathway IEA
    Inferred from Electronic Annotation
    more info
     
    involved_in innate immune response IEA
    Inferred from Electronic Annotation
    more info
     
    involved_in proteolysis IEA
    Inferred from Electronic Annotation
    more info
     

    General protein information

    Preferred Names
    complement factor I
    Names
    C3B/C4B inactivator
    C3b-inactivator
    Konglutinogen-activating factor
    complement component I
    complement control protein factor I
    complement factor I heavy chain
    light chain of factor I
    NP_000195.3
    NP_001304986.2
    NP_001317964.1
    NP_001362207.1
    NP_001362208.1
    NP_001362209.1
    NP_001362210.1
    NP_001362211.1
    NP_001362212.1
    NP_001362213.1
    XP_006714273.1
    XP_011530222.1
    XP_047271609.1
    XP_047271610.1
    XP_054205914.1
    XP_054205915.1
    XP_054205916.1
    XP_054205917.1
    XP_054205918.1
    XP_054205919.1
    XP_054205920.1
    XP_054205921.1
    XP_054205922.1

    NCBI Reference Sequences (RefSeq)

    NEW Try the new Transcript table

    RefSeqs maintained independently of Annotated Genomes

    These reference sequences exist independently of genome builds. Explain

    These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

    Genomic

    1. NG_007569.1 RefSeqGene

      Range
      4807..66294
      Download
      GenBank, FASTA, Sequence Viewer (Graphics), LRG_48

    mRNA and Protein(s)

    1. NM_000204.5NP_000195.3  complement factor I isoform 2 preproprotein

      Status: REVIEWED

      Description
      Transcript Variant: This variant (2) encodes isoform 2.
      Source sequence(s)
      AC126283
      Consensus CDS
      CCDS34049.1
      UniProtKB/Swiss-Prot
      O60442, P05156
      UniProtKB/TrEMBL
      A8K3L0
      Related
      ENSP00000378130.2, ENST00000394634.7
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:340572
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    2. NM_001318057.2NP_001304986.2  complement factor I isoform 1 preproprotein

      Status: REVIEWED

      Description
      Transcript Variant: This variant (1) contains an alternate in-frame exon compared to variant 2. The encoded isoform (1) is longer than isoform 2.
      Source sequence(s)
      AC126283
      Consensus CDS
      CCDS82946.1
      UniProtKB/TrEMBL
      B4DRF2, E7ETH0
      Related
      ENSP00000378131.3, ENST00000394635.8
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:348580
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    3. NM_001331035.2NP_001317964.1  complement factor I isoform 3 preproprotein

      Status: REVIEWED

      Description
      Transcript Variant: This variant (3) lacks an alternate in-frame exon in the central coding region compared to variant 2. The encoded isoform (3) lacks a portion of the heavy chain compared to isoform 2.
      Source sequence(s)
      AK290625, BM955734, BX453590, DC392360, J02770, N63668
      Consensus CDS
      CCDS82945.1
      UniProtKB/TrEMBL
      A8K3L0, G3XAM2
      Related
      ENSP00000427438.1, ENST00000512148.5
      Conserved Domains (7) summary
      smart00020
      Location:332562
      Tryp_SPc; Trypsin-like serine protease
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:333565
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
      pfam00530
      Location:119214
      SRCR; Scavenger receptor cysteine-rich domain
    4. NM_001375278.1NP_001362207.1  complement factor I isoform 4 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC004067, AC126283
      UniProtKB/TrEMBL
      B4DRF2
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:348519
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    5. NM_001375279.1NP_001362208.1  complement factor I isoform 5 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC004067, AC126283
      UniProtKB/TrEMBL
      A8K3L0
      Related
      ENST00000695844.1
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:340511
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    6. NM_001375280.1NP_001362209.1  complement factor I isoform 6 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC004067, AC126283
      UniProtKB/TrEMBL
      A8K3L0
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:333504
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    7. NM_001375281.1NP_001362210.1  complement factor I isoform 7 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC004067, AC126283
      UniProtKB/TrEMBL
      A8K3L0
      Related
      ENST00000695845.1
      Conserved Domains (5) summary
      smart00020
      Location:339511
      Tryp_SPc; Trypsin-like serine protease
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    8. NM_001375282.1NP_001362211.1  complement factor I isoform 8 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC004067, AC126283
      UniProtKB/TrEMBL
      A8K3L0
      Conserved Domains (5) summary
      smart00020
      Location:332504
      Tryp_SPc; Trypsin-like serine protease
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    9. NM_001375283.1NP_001362212.1  complement factor I isoform 9 preproprotein

      Status: REVIEWED

      Source sequence(s)
      AC126283
      UniProtKB/TrEMBL
      A8K3L0
      Conserved Domains (5) summary
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:321553
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
    10. NM_001375284.1NP_001362213.1  complement factor I isoform 10

      Status: REVIEWED

      Source sequence(s)
      AC126283
      Conserved Domains (3) summary
      cd00112
      Location:2153
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:137369
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:5490
      Ldl_recept_a; Low-density lipoprotein receptor domain class A

    RNA

    1. NR_164671.1 RNA Sequence

      Status: REVIEWED

      Source sequence(s)
      AC126283
    2. NR_164672.1 RNA Sequence

      Status: REVIEWED

      Source sequence(s)
      AC126283
    3. NR_164673.1 RNA Sequence

      Status: REVIEWED

      Source sequence(s)
      AC126283

    RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2024_08

    The following sections contain reference sequences that belong to a specific genome build. Explain

    Reference GRCh38.p14 Primary Assembly

    Genomic

    1. NC_000004.12 Reference GRCh38.p14 Primary Assembly

      Range
      109730982..109801999 complement
      Download
      GenBank, FASTA, Sequence Viewer (Graphics)

    mRNA and Protein(s)

    1. XM_011531920.3XP_011530222.1  complement factor I isoform X1

      UniProtKB/TrEMBL
      B4DRF2
      Conserved Domains (8) summary
      smart00020
      Location:347519
      Tryp_SPc; Trypsin-like serine protease
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:348519
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
      pfam00530
      Location:119214
      SRCR; Scavenger receptor cysteine-rich domain
      pfam13900
      Location:524555
      GVQW; Putative domain of unknown function
    2. XM_047415653.1XP_047271609.1  complement factor I isoform X2

      UniProtKB/TrEMBL
      B4DRF2
    3. XM_047415654.1XP_047271610.1  complement factor I isoform X4

      UniProtKB/TrEMBL
      A8K3L0
    4. XM_006714210.5XP_006714273.1  complement factor I isoform X3

      UniProtKB/TrEMBL
      B4DRF2
      Conserved Domains (7) summary
      smart00020
      Location:347520
      Tryp_SPc; Trypsin-like serine protease
      smart00057
      Location:43108
      FIMAC; factor I membrane attack complex
      smart00202
      Location:114215
      SR; Scavenger receptor Cys-rich
      cd00112
      Location:224256
      LDLa; Low Density Lipoprotein Receptor Class A domain, a cysteine-rich repeat that plays a central role in mammalian cholesterol metabolism; the receptor protein binds LDL and transports it into cells by endocytosis; 7 successive cysteine-rich repeats of about ...
      cd00190
      Location:348520
      Tryp_SPc; Trypsin-like serine protease; Many of these are synthesized as inactive precursor zymogens that are cleaved during limited proteolysis to generate their active forms. Alignment contains also inactive enzymes that have substitutions of the catalytic triad ...
      pfam00057
      Location:257293
      Ldl_recept_a; Low-density lipoprotein receptor domain class A
      pfam00530
      Location:119214
      SRCR; Scavenger receptor cysteine-rich domain

    Alternate T2T-CHM13v2.0

    Genomic

    1. NC_060928.1 Alternate T2T-CHM13v2.0

      Range
      113031939..113104052 complement
      Download
      GenBank, FASTA, Sequence Viewer (Graphics)

    mRNA and Protein(s)

    1. XM_054349941.1XP_054205916.1  complement factor I isoform X6

      UniProtKB/TrEMBL
      A8K3L0
    2. XM_054349940.1XP_054205915.1  complement factor I isoform X1

      UniProtKB/TrEMBL
      B4DRF2
    3. XM_054349944.1XP_054205919.1  complement factor I isoform X8

      UniProtKB/TrEMBL
      A8K3L0
    4. XM_054349943.1XP_054205918.1  complement factor I isoform X7

      UniProtKB/TrEMBL
      B4DRF2
    5. XM_054349942.1XP_054205917.1  complement factor I isoform X2

      UniProtKB/TrEMBL
      B4DRF2
    6. XM_054349947.1XP_054205922.1  complement factor I isoform X4

      UniProtKB/TrEMBL
      A8K3L0
    7. XM_054349946.1XP_054205921.1  complement factor I isoform X9

      UniProtKB/TrEMBL
      A8K3L0
    8. XM_054349939.1XP_054205914.1  complement factor I isoform X5

      UniProtKB/TrEMBL
      B4DRF2
    9. XM_054349945.1XP_054205920.1  complement factor I isoform X3

      UniProtKB/TrEMBL
      B4DRF2