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FLASH GENE
Symbol CFI contributors: mct/npt - updated : 25-01-2022
HGNC name complement factor I
HGNC id 5394
Corresponding disease
CFID complement factor I ('eye') deficiency
Location 4q25      Physical location : 110.661.849 - 110.723.335
Synonym name
  • C3-inactivator
  • light chain of factor I
  • I factor (complement)
  • konglutinogen-activating factor
  • light chain of factor I
  • Synonym symbol(s) C3I, FI, C3b-INA, KAF, IF
    EC.number 3.4.21.45
    DNA
    TYPE functioning gene
    STRUCTURE 61.49 kb     13 Exon(s)
    MAPPING cloned Y linked Y status confirmed
    Map cen - GC - CXCL10 - ADH5 - EGF - IF - IL2 IL2 - MNS - qter
    Authors Shiang (99)
    RNA
    TRANSCRIPTS type messenger
    identificationnb exonstypebpproduct
    ProteinkDaAAspecific expressionYearPubmed
    13 - 2171 - 583 - 2013 23685748
    12 - 1902 - 540 - 2013 23685748
    13 - 2040 - 586 - 2013 23685748
    13 - 1923 - 547 - 2013 23685748
    14 - 2061 - 593 - 2013 23685748
    15 - 2085 - 601 - 2013 23685748
    11 - 1921 - 564 - 2013 23685748
    11 - 1553 - 380 - 2013 23685748
    14 - 2002 - 591 - 2013 23685748
    12 - 1957 - 576 - 2013 23685748
    EXPRESSION
    Type restricted
       expressed in (based on citations)
    organ(s)
    SystemOrgan level 1Organ level 2Organ level 3Organ level 4LevelPubmedSpeciesStageRna symbol
    Digestiveliver    
    Nervousbrain    
    Urinarykidney    
    cell lineage
    cell lines
    fluid/secretion plasma
    at STAGE
    PROTEIN
    PHYSICAL PROPERTIES
    STRUCTURE
    motifs/domains
  • one SRCR domain
  • two LDL-receptor class A domains
  • one peptidase S1 domain
  • conjugated GlycoP
    mono polymer heteromer , dimer
    isoforms Precursor with two alternatively spliced isoforms C3I alpha, C3I beta
    HOMOLOGY
    Homologene
    FAMILY
  • trypsin-like family of serine proteinases
  • peptidase S1 family
  • CATEGORY enzyme
    SUBCELLULAR LOCALIZATION extracellular
        plasma membrane
        intracellular
    intracellular,cytoplasm
    basic FUNCTION
  • serine proteinase that modulates the complement cascade by regulating the levels of C3 convertases
  • inactivating complement subcomponents C3b, iC3b and C4b by proteolytic cleavage
  • two-chain serine protease in which the light chain carries the catalytic domain while the heavy chain's function is unclear (Kavanagh 2008)
  • crucial regulator of mammalian complement activity (Shin 2009)
  • destroying the hemolytic and immune-adherence activities of cell-bound, activated C3
  • is a serum protease that inhibits all complement pathways
  • CELLULAR PROCESS protein, degradation
    PHYSIOLOGICAL PROCESS immunity/defense
    text
  • anti-pathogen response
  • innate immunity
  • PATHWAY
    metabolism
    signaling
    a component
  • component 3 of complement
  • heterodimer of a light and a heavy chains linked by disulfide bonds
  • INTERACTION
    DNA
    RNA
    small molecule cofactor,
  • factor H
  • protein
    cell & other
    REGULATION
    Other markedly activated HF1 and MCP (membrane cofactor protein)
    ASSOCIATED DISORDERS
    corresponding disease(s) CFID
    Other morbid association(s)
    TypeGene ModificationChromosome rearrangementProtein expressionProtein Function
    constitutional germinal mutation      
    complement factor 1 deficiency
    constitutional germinal mutation      
    glomerulonephrites C3
    constitutional       loss of function
    can result in uncontrolled activation of the complement pathways in the brain resulting in devastating cerebral inflammation
    constitutional germinal mutation      
    in Acute Hemorrhagic Leukoencephalitis (AHLE), a rare demyelinating disorder of acute onset, rapid deterioration and significant morbidity and mortality
    constitutional     --over  
    of complement factor I might have an impact on the development of Autism spectrum disorders (ASDs)
    Susceptibility
  • to atypical hemolytic uremic syndrome
  • to age-related macular degeneration (AMD)
  • Variant & Polymorphism other
  • CFI mRNA encoding Arg119 had reduced activity and contribute to the genetic burden of AMD
  • Candidate gene
    Marker
  • serum CFI level may not only be a promising biomarker for disease activity of SLE, but also reflects the hematological features of systemic lupus erythematosus (SLE)
  • Therapy target
    ANIMAL & CELL MODELS