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C-reactive protein; contains: C-reactive protein(1-205) (CRP PTX1)

A pentraxin or pentaxin. Function: - acute phase reactant - displays several functions associated with host defense: - promotes agglutination, bacterial capsular swelling, phagocytosis & complement fixation through Ca+2-dependent binding to phosphatidylcholine - CRP also binds nucleic acids - can interact with DNA & histones & may scavenge nuclear material released from damaged circulating cells - CRP binds to polysaccharides present in bacteria, fungi, parasites & protozoal parasites - once bound, CRP activates classical complement pathway. - other effects of CRP: a) inhibition of nitric oxide formation b) upregulation of angiotensin receptors Cofactor: binds 2 Ca+2 per subunit Structure: - homopentamer - belongs to the pentraxin family - contains 1 pentraxin domain - pentraxin (or pentaxin) have a discoid arrangement of 5 non-covalently bound subunits Compartment: secreted Alternative splicing: named isoforms=2 Expression: - found in plasma - concentration of CRP in plasma increases greatly during acute phase response to tissue injury, infection or other inflammatory stimuli - induced by IL-1 & IL-6/ Pathology: - CRP polymorphisms associated with both elevated serum CRP levels & risk of cardiovascular disease in the elderly (NOT all data consistent) Notes: - The "C" stands for "C-polysaccharide of pneumococcus"

Related

C-reactive protein (CRP) in serum/plasma complement cascade

General

acute phase protein gamma globulin pentraxin-2 (neuronal pentraxin, NPTX)

Properties

CONFIGURATION: pentamer SIZE: entity length = 224 aa MW = 25 kD COMPARTMENT: plasma MOTIF: signal sequence {1-18} Pentraxin {19-224} MOTIF: cysteine residue {C54} MODIFICATION: cysteine residue {C115} Ca+2-binding site SITE: 78-78 Ca+2-binding site SITE: 79-79 cysteine residue {C115} MODIFICATION: cysteine residue {C54} Ca+2-binding site SITE: 156-156 Ca+2-binding site SITE: 157-157 Ca+2-binding site SITE: 158-158 Ca+2-binding site SITE: 168-168 SECRETED-BY: hepatocyte MISC-INFO: CONCENTRATION 0.4-1.3 UG/DL

Database Correlations

OMIM 123260 UniProt P02741 Pfam PF00354 Entrez Gene 1401 Kegg hsa:1401

References

  1. Tietz Fundamentals of Clinical Chemistry 3rd ed, WB Saunders, 1987 pg 334
  2. Clinical Diagnosis & Management by Laboratory Methods, J.B. Henry (ed), W.B. Saunders Co., Philadelphia, PA. 1991, pg 224
  3. Journal Watch 24(3):22, 2004 Sesso HD et al, JAMA 290:2945, 2003 PMID: 14665655 Grundy SM et al, JAMA 290:3000, 2003
  4. Lange LA et al, Association of polymorphisms in the CRP gene with circulating C-reactive protein levels and cardiovascular events. JAMA 2006, 296:2703 PMID: 17164456
  5. UniProt :accession P02741
  6. Wikipedia; Note: C-reactive protein entry http://en.wikipedia.org/wiki/C-reactive_protein
  7. SeattleSNPs http://pga.gs.washington.edu/data/crp/
  8. Protein Spotlight; Note: No more christmas pudding? - Issue 30 of January 2003 http://web.expasy.org/spotlight/back_issues/sptlt030.shtml