WordNet

make complete or perfect; supply what is wanting or form the complement to; "I need some pepper to complement the sweet touch in the soup"
a complete number or quantity; "a full complement"
one of a series of enzymes in the blood serum that are part of the immune response
something added to complete or embellish or make perfect; "a fine wine is a perfect complement to the dinner"; "wild rice was served as an accompaniment to the main dish" (同)accompaniment
number needed to make up a whole force; "a full complement of workers" (同)full complement
a word or phrase used to complete a grammatical construction
either of two parts that mutually complete each other
be a contributing factor; "make things factor into a companys profitability"
any of the numbers (or symbols) that form a product when multiplied together
an independent variable in statistics
anything that contributes causally to a result; "a number of factors determined the outcome"
consider as relevant when making a decision; "You must factor in the recent developments" (同)factor in, factor out
resolve into factors; "a quantum computer can factor the number 15" (同)factor in, factor out
an event known to have happened or something known to have existed; "your fears have no basis in fact"; "how much of the story is fact and how much fiction is hard to tell"
a concept whose truth can be proved; "scientific hypotheses are not facts"
a piece of information about circumstances that exist or events that have occurred; "first you must collect all the facts of the case"
a statement or assertion of verified information about something that is the case or has happened; "he supported his argument with an impressive array of facts"
the 9th letter of the Roman alphabet (同)i

PrepTutorEJDIC

(あるものを完全にするため)(…を)補う物(事)《+『of』+『名』》 / 補語(文法で文の成分の一つ) / (必要な)全数,全量;(船の)定員 / …を補足する,補う
(…の)『要因』,(…を生み出す)要素《+『in』+『名』(do『ing』)》 / 囲数,約数 / 代理人,《おもに英》仲買人 / =factorize
〈C〉『事実』,実際にある(あった)事 / 〈U〉真相,真実(truth) / 《the~》(法律用語で)犯行
『私は』私が
iodineの化学記号

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/04/29 09:35:36」(JST)

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Complement factor I, also known as C3b/C4b inactivator, is a protein that in humans is encoded by the CFI gene.^[1]^[2]

Complement Factor I (fI) is a protein of the complement system, first isolated in 1966 in guinea pig serum,^[3] that regulates complement activation by cleaving cell-bound or fluid phase C3b and C4b.^[4]

Pathology

Factor I deficiency in turn leads to low levels of complement component 3 (C3) in plasma, due to unregulated activation of the complement alternative pathway, and it has been associated with recurrent bacterial infections in children; more recently, mutations in the Factor I gene have been shown to be implicated^[5] in development of Haemolytic Uremic Syndrome, a renal disease also caused by unregulated complement activation.

Synthesis

The gene for Factor I in humans is located on chromosome 4.^[2] Factor I is synthesised mostly in the liver, and is initially secreted as a single 88 kDalton gene product; this precursor protein is then cleaved by furin to yield the mature fI protein, which is a disulfide-linked dimer of heavy chain (residues 19-335, 51 kDalton) and light chain (residues 340-583, 37 kDalton). Only the mature protein is active.

Structure

Both heavy and light chains bear Asn-linked glycans, on three distinct glycosylation sites each.

The fI heavy chain has four domains: a FIMAC domain, a Scavenger Receptor Cysteine Rich (SRCR) domain and two LDL-receptor Class A domains; the heavy chain plays an inhibitory role in maintaining the enzyme inactive until it meets the complex formed by the substrate (either C3b or C4b) and a cofactor protein (Factor H, CR1, MCP or C4BP). Upon binding of the enzyme to the substrate:cofactor complex, the heavy:light chain interface is disrupted, and the enzyme activated by allostery.^[6] The LDL-receptor domains contain one Calcium-binding site each.

The fI light chain is the serine protease domain containing the catalytic triad responsible for specific cleavage of C3b and C4b. Conventional protease inhibitors do not completely inactivate Factor I^[7] but they can do so if the enzyme is pre-incubated with its substrate: this supports the proposed rearrangement of the molecule upon binding to the substrate.

Genetic polymorphism in Factor I has been observed^[8] and recently explained in terms of variants R201S, R406H, R502L.^[9]

Crystal structure the crystal structure of human Factor I has been deposited as PDB 2XRC.

References

^ "Entrez Gene: complement factor I".
^ ^a ^b Goldberger G, Bruns GA, Rits M, Edge MD, Kwiatkowski DJ (July 1987). "Human complement factor I: analysis of cDNA-derived primary structure and assignment of its gene to chromosome 4". J. Biol. Chem. 262 (21): 10065–71. PMID 2956252.
^ Nelson R, Jensen J, Gigli I, Tamura N (1966). "Methods for the separation, purification and measurement of nine components of hemolytic complement in guinea-pig serum". Immunochemistry 3 (2): 111–35. doi:10.1016/0019-2791(66)90292-8. PMID 5960883.
^ Lachmann P, Müller-Eberhard H (1968). "The demonstration in human serum of "conglutinogen-activating factor" and its effect on the third component of complement". J Immunol 100 (4): 691–8. PMID 5645214.
^ Saunders R, Abarrategui-Garrido C, Frémeaux-Bacchi V, Goicoechea de Jorge E, Goodship T, López Trascasa M, Noris M, Ponce Castro I, Remuzzi G, Rodríguez de Córdoba S, Sánchez-Corral P, Skerka C, Zipfel P, Perkins S (2007). "The interactive Factor H-atypical hemolytic uremic syndrome mutation database and website: update and integration of membrane cofactor protein and Factor I mutations with structural models". Hum Mutat 28 (3): 222–34. doi:10.1002/humu.20435. PMID 17089378.
^ Roversi P, Johnson S, Caesar JJE, McLean F, Leath KJ, Tsiftsoglou SA, Morgan BP, Harris CL, Sim RB, Lea SML (2011). "Structural basis for complement factor I control and its disease-associated sequence polymorphisms)". PNAS 108 (31): 12839–12844. PMID 21768352.
^ ,Ekdahl KN, Nilsson UR, Nilsson B. (1990). "Inhibition of factor I by diisopropylfluorophosphate. Evidence of conformational changes in factor I induced by C3b and additional studies on the specificity of factor I". J. Immunology 144 (11): 4269–74. PMID 2140392.
^ Nakamura S, Abe K (1985). "Genetic polymorphism of human factor I (C3b inactivator)". Hum Genet 71 (1): 45–8. doi:10.1007/BF00295667. PMID 3897024.
^ Yuasa I et al. (2008). "Molecular basis of complement factor I (CFI) polymorphism: one of two polymorphic suballeles responsible for CFI A is Japanese-specific". J. Hum Genet 53 (11–12): 1016–21. doi:10.1007/s10038-008-0337-4. PMID 18825487.

External links

GeneReviews/NCBI/NIH/UW entry on Atypical Hemolytic-Uremic Syndrome
OMIM entries on Atypical Hemolytic-Uremic Syndrome
The MEROPS online database for peptidases and their inhibitors: S01.199

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UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 補体系の遺伝性疾患 inherited disorders of the complement system
2. 補体介在性溶血性尿毒症症候群 complement mediated hemolytic uremic syndrome
3. 内皮：プライマー the endothelium a primer

English Journal

New perspectives on role of tumor microenvironment in progression of cutaneous squamous cell carcinoma.

Nissinen L1,2, Farshchian M1,2, Riihilä P1,2, Kähäri VM3,4.
Cell and tissue research.Cell Tissue Res.2016 Jul 14. [Epub ahead of print]
Epidermal keratinocyte-derived cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer, and its incidence is increasing worldwide. Solar UV radiation is an important risk factor for cSCC and leads to genetic and epigenetic changes both in epidermal keratinocytes and dermal
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[Hemolytic kidney failure and transient ischemic attack in a 32-year-old female].

Anders R1, Grohmann M2, Lindner TH1, Bergmann C2, Halbritter J3.
Der Internist.Internist (Berl).2016 Jun 29. [Epub ahead of print]
We report on the case of a 32-year-old female patient who initially presented with oliguric acute renal failure, hemolytic anemia with moderate thrombocytopenia and subsequently developed a transient ischemic attack in the cerebellum. The kidney biopsy revealed clinically suspected atypical hemolyt
PMID 27357251

Age-related macular degeneration: Complement in action.

van Lookeren Campagne M1, Strauss EC2, Yaspan BL3.
Immunobiology.Immunobiology.2016 Jun;221(6):733-9. doi: 10.1016/j.imbio.2015.11.007. Epub 2015 Dec 19.
The complement system plays a key role in host-defense against common pathogens but must be tightly controlled to avoid inflammation and tissue damage. Polymorphisms in genes encoding two important negative regulators of the alternative complement pathway, complement factor H (CFH) and complement fa
PMID 26742632

Japanese Journal

補体からみたIgA腎症の病態の解明 (AYUMI 補体関連疾患の新局面)

医学のあゆみ 257(8), 832-836, 2016-05-21
NAID 40020824662

非負値行列因子分解による産業クラスター検出の試み

水産大学校研究報告 64(4), 227-239, 2016-03
NAID 120005860867

Dynamics of circulating tumor DNA represented by the activating and resistant mutations in the EGFR-TKI treatment

Cancer Science 107(3), 353-358, 2016-03
NAID 120005767021

Related Pictures

★リンクテーブル★

リンク元	「補体I因子」「補体因子I」
関連記事	「complement」「I」「fact」「factor」「Id」

「補体I因子」

Complement factor I
Available structures
PDB	Ortholog search: PDBe, RCSB
List of PDB id codes
	2XRC
Identifiers
Symbols	CFI; AHUS3; C3BINA; C3b-INA; FI; IF; KAF
External IDs	OMIM: 217030 MGI: 105937 HomoloGene: 171 GeneCards: CFI Gene
EC number	3.4.21.45
Gene Ontology
Molecular function	• serine-type endopeptidase activity; • scavenger receptor activity; • metal ion binding;
Cellular component	• extracellular region; • extracellular space; • membrane;
Biological process	• proteolysis; • complement activation, classical pathway; • regulation of complement activation; • innate immune response;
	Sources: Amigo / QuickGO
Orthologs
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