Double-stranded DNA and chromatin Serum amyloid P binds DNA and chromatin Authored: Jupe, S, 2010-10-15 Edited: Jupe, S, 2011-04-08 Pubmed10371509 Pubmed2358775 Pubmed3675579 Pubmed8033412 Reactome Database ID Release 43977224 Reactome, http://www.reactome.org ReactomeREACT_75858 Reviewed: Perry, G, 2011-04-08 Serum amyloid P component (SAP) binds DNA and chromatin in a calcium dependent manner in physiological conditions (Pepys et al. 1987). This binding displaces H1-type histones (Butler et al. 1990), solubilizing chromatin which is otherwise insoluble in extracellular fluids. SAP may therefore participate in the in vivo handling of chromatin exposed by cell death. SAP knockout mice spontaneously develop antinuclear autoimmunity and severe glomerulonephritis, a phenotype resembling human systemic lupus erythematosus, a serious autoimmune disease, suggesting that SAP binding may play a role in reducing the immunogenicity of chromatin and preventing autoimmunity (Bickerstaff et al. 1999). Serum amyloid P-component pentamer:Double-stranded DNA Serum amyloid P-component homopentamer