xpression was induced by the addition of isopropyl-thiogalactopyranoside, 0.1 mM, at 20uC. Cells were harvested and lysed by French press. The lysate was cleared by centrifugation at 
16,000 RPM for 30 minutes. The supernatant was purified in two steps: by Ni-NTA chromatography followed by gel filtration chromatography . A. fulgidus S2p was expressed and purified under the same conditions. Acknowledgments Protein Binding ELISA ELISA plates were coated with 1.5 mg per well of either filamentous actin or preformed microtubules dissolved in coating buffer overnight at 4uC. Plates were washed with wash buffer. Plates were then incubated in blocking buffer for 1 hour at 37uC. After incubation, plates were washed with wash buffer, 3 times for 5 minutes each. Triplicate wells were incubated We thank Dr. Christine Pampeno for the critical reading of this manuscript. Author Contributions Conceived and designed the experiments: LV KVJ DM. Performed the experiments: LV. Analyzed the data: LV. Contributed reagents/materials/ analysis tools: LV KVJ DM. Wrote the paper: LV KVJ DM. 10 January 2011 | Volume 6 | Issue 1 | e15895 Laminin Receptor and the Cytoskeleton 22. Demianova M, Formosa TG, Ellis SR Yeast proteins related to the p40/ laminin receptor precursor are essential components of the 3131684 40 S ribosomal subunit. J Biol Chem 271: 113831391. 23. Ford CL, Randal-Whitis L, Ellis SR Yeast proteins related to the p40/ laminin receptor precursor are required for 20S ribosomal RNA processing and the maturation of 40S ribosomal subunits. Cancer Res 59: 70410. 24. Susantad T, Smith DR siRNA-mediated silencing of the 37/67-kDa high affinity laminin receptor in Hep3B cells induces apoptosis. Cell Mol Biol Lett 13: 45264. 25. Kaneda Y, Kinoshita K, Sato M, Saeki Y, Yamada R, et al. The induction of apoptosis in HeLa cells by the loss of LBP-p40. Cell Death Differ 5: 208. 26. Scheiman J, Jamieson KV, Ziello J, Tseng JC, and Meruelo D Extraribosomal functions associated with the c terminus of the 37/67 kDa laminin receptor are required for maintaining cell viability. Cell Death and Disease 1: 1. 27. Brown SS, Malinoff HL, Wicha MS Connectin: cell surface protein that binds both laminin and actin. Proc Natl Acad Sci U S A 80: 5927930. 28. Cody RL, Wicha MS Clustering of cell surface laminin enhances its association with the cytoskeleton. Exp Cell Res 165: 10716. 29. Yannariello-Brown J, Wewer U, Liotta L, Madri JA Distribution of a 69kD laminin-binding protein in aortic and microvascular endothelial cells: modulation during cell attachment, spreading, and migration. J Cell Biol 106: 1773786. 30. Brown S, Levinson W, Spudich JA Cytoskeletal elements of chick embryo R-7128 chemical information fibroblasts revealed by detergent extraction. J Supramol Struct 5: 11930. 31. Goldman RD, Lazarides E, Pollack R, Weber K The distribution of actin in non-muscle cells. The use of actin antibody in the localization of actin within the microfilament bundles of mouse 3T3 cells. Exp Cell Res 90: 33344. 32. Lazarides E Intermediate filaments as mechanical integrators of cellular space. Nature 283: 24956. 33. Osborn M, Weber K The detertent-resistant cytoskeleton of tissue culture cells includes the nucleus and the microfilament bundles. Exp Cell Res 106: 33949. 34. Goldberg MB Actin-based motility of intracellular microbial pathogens. Microbiol Mol Biol Rev 65: 59526, table of contents. 35. Pollard TD, Borisy GG Cellular motility driven by assembly and disassembly of actin filaments. Cell 112: 45365. 36. Mi
