Complement C1r subcomponent (, ''activated complement C1r'', ''C overbar 1r esterase'', ''C1r'') is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
involved in the
complement system
The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and at ...
of the
innate immune system
The innate, or nonspecific, immune system is one of the two main immunity strategies (the other being the adaptive immune system) in vertebrates. The innate immune system is an older evolutionary defense strategy, relatively speaking, and is the ...
.
In humans, C1r is encoded by the ''C1R''
gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...
.
C1r along with
C1q
The complement component 1q (or simply C1q) is a protein complex involved in the complement system, which is part of the innate immune system. C1q together with C1r and C1s form the C1 complex.
Antibodies of the adaptive immune system can bind ...
and
C1s
Complement component 1s (, '' C1 esterase'', ''activated complement C1s'', ''complement C overbar 1r'', ''C1s'') is a protein involved in the complement system. C1s is part of the C1 complex. In humans, it is encoded by the ''C1S'' gene.
C1s cle ...
form the
C1 complex
The C1 complex (''complement component 1'', ''C1'') is a protein complex involved in the complement system. It is the first component of the classical complement pathway and is composed of the subcomponents C1q, C1r and C1s.
Structure
The C1 ...
, which is the first component of the serum
complement system
The complement system, also known as complement cascade, is a part of the immune system that enhances (complements) the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and at ...
. C1r is an
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...
that activates C1s to its active form, by
proteolytic
Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called proteases, ...
cleavage.
Clinical significance
*
Ehlers-Danlos syndrome Periodontal type is associated with mutations in the ''CR1''
gene
In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...
Function
C1r has been shown to
interact
Advocates for Informed Choice, dba interACT or interACT Advocates for Intersex Youth, is a 501(c)(3) nonprofit organization using innovative strategies to advocate for the legal and human rights of children with intersex traits. The organizati ...
with
C1s
Complement component 1s (, '' C1 esterase'', ''activated complement C1s'', ''complement C overbar 1r'', ''C1s'') is a protein involved in the complement system. C1s is part of the C1 complex. In humans, it is encoded by the ''C1S'' gene.
C1s cle ...
. C1r
cleaves Cleaves is a surname. Notable people with the surname include:
* Henry B. Cleaves
*Jessica Cleaves (1948–2014), American singer-songwriter
*Margaret Cleaves (1848–1917), American physician
*Mateen Cleaves (born 1977), American basketball player ...
C1s to form the active form of C1s.
References
Further reading
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External links
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Complement system
EC 3.4.21
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