title: Crystal structure study on human S100A13 at 2.0 A resolution.
abstract: The S100 protein family is the largest group of calcium-binding protein families, which consists of at least 25 members. S100A13, which is widely expressed in a variety of tissues, is a unique member of the S100 protein family. Previous reports showed that S100A13 might be involved in the stress-induced release of some signal peptide-less proteins (such as FGF-1 and IL-1alpha) and also associated with inflammatory functions. It was also reported that S100A13 is a new angiogenesis marker. Here we report the crystal structure of the Ca(2+)-bound form of S100A13 at 2.0 A resolution. S100A13 is a homodimer with four EF-hand motifs in an asymmetric unit, displaying a folding pattern similar to other S100 members. However, S100A13 has the unique structural feature with all alpha-helices being amphiphilic, which was not found in other members of S100s. We propose that this characteristic structure of S100A13 might be related to its ability to mediate the release of FGF-1 and IL-1alpha.
authors: National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China. meili@moon.ibp.ac.cn
authors: Mei
authors: M
authors: Li
authors: Ping-Feng
authors: PF
authors: Zhang
authors: Xiao-Wei
authors: XW
authors: Pan
authors: Wen-Rui
authors: WR
authors: Chang
mesh_terms: D018360:Crystallography, X-Ray; D019281:Dimerization; D006801:Humans; D008958:Models, Molecular; D009418:S100 Proteins / Q000737:chemistry*; D020349:Surface Plasmon Resonance
chemical_list: D009418:S100 Proteins; C511523:S100A13 protein, human