FGF1-S100A13 complex structure: key component in non-classical path way of FGF1
[FGF1_HUMAN] Plays an important role in the regulation of cell survival, cell division, angiogenesis, cell differentiation and cell migration. Functions as potent mitogen in vitro.   [S10AD_HUMAN] Plays a role in the export of proteins that lack a signal peptide and are secreted by an alternative pathway. Binds two calcium ions per subunit. Binds one copper ion. Binding of one copper ion does not interfere with calcium binding. Required for the copper-dependent stress-induced export of IL1A and FGF1. The calcium-free protein binds to lipid vesicles containing phosphatidylserine, but not to vesicles containing phosphatidylcholine (By similarity). 
Publication Abstract from PubMed
Fibroblast growth factors (FGFs) are key regulators of cell proliferation, tumor-induced angiogenesis, and migration. FGFs are essential for early embryonic development, organ formation, and angiogenesis. FGF1 also plays an important role in inflammation, wound healing, and restenosis. The biological effects of FGF1 are mediated through the activation of the four transmembrane phosphotyrosine kinase fibroblast growth factor receptors in the presence of heparin sulfate proteoglycans and, therefore, require the release of the protein into the extracellular space. FGF1 is exported through a non-classical release pathway involving the formation of a specific multiprotein complex. The protein constituents of this complex include FGF1, S100A13, and the p40 form of synaptotagmin 1 (Syt1). Because FGF1 plays an important role in tumor formation, it is clear that preventing the formation of the multiprotein complex would be an effective strategy to inhibit a wide range of cancers. To understand the molecular events in the FGF1 release pathway, we studied the FGF1-S100A13 tetrameric and FGF1-S100A13-C2A hexameric complex structures, which are both complexes possibly formed during the non-classical pathway of FGF1 release.
The heterohexameric complex structure, a component in the non-classical pathway for fibroblast growth factor 1 (FGF1) secretion.,Mohan SK, Rani SG, Yu C J Biol Chem. 2010 May 14;285(20):15464-75. Epub 2010 Mar 10. PMID:20220137
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.