the a-tubulin localization, taxol treatment resulted in an alteration of tubulin structure. The alteration in tubulin structure was likely the result of a long incubation with taxol and not a loss of cell viability, which was monitored in parallel. Treatment with taxol also had a dramatic effect on both LamR and S6 localization, causing both proteins to adopt a diffuse staining pattern. The association between a-tubulin and 40S ribosomal components S6 and LamR indicates that this interaction is related to cellular translation. To further characterize the relationship between tubulin and protein synthesis, cells were treated with either CB or taxol and subjected to 35S labeling. Interestingly, there was no change in protein synthesis in cells treated with CB. However, in cells treated with taxol, new protein synthesis was significantly decreased. These data indicate that tubulin plays a critical role in mediating cellular translation. Results LamR Localization LamR is an integral ribosomal component, which is required for protein translation. Through the use of immunofluorescence, we 
confirmed co-localization of LamR with S6, used throughout this study as a marker for the 40S ribosomal subunit. In order to study LamR interactions with cytoskeletal components, we examined the cellular localization of a-tubulin in relation to LamR. These data revealed that LamR also colocalizes with a-tubulin, which indicates that LamR in complex with the ribosome may be associated with tubulin. Characterization of the LamR-a-Tubulin Interaction To study interactions between the ribosome and a-tubulin, siRNA was employed to ablate expression of either LamR or S6 ribosomal protein. LamR-specific siRNA successfully ablates expression of both the 37 and 67 kDa forms of the protein. Successful knockdown of LamR and S6 was confirmed by western blot analysis. Although knockdown of S6 expression was less efficient than LamR, 35S labeling confirmed inhibition of protein synthesis. siGLO, a RISC free fluorescently conjugated control oligo, coupled with FACS analysis was utilized to assess transfection efficiency. siLamR and siS6 treated samples were subjected to immunofluorescence to Characterization of the LamR-Actin Interaction LamR interactions with tubulin appear to mediate INCB024360 site translation and are concentrated within the intracellular environment. Interactions between LamR and actin appear to affect extracellular functions. Under normal cell culture conditions, LamR did not co-localize with F-actin at the cell surface. Plating cells on laminin coated chamber slides induced a change in both cell morphology and LamR localization. The presence of laminin on the culture January 2011 | Volume 6 | Issue 1 | e15895 Laminin Receptor and the Cytoskeleton dish induced the reorganization of actin filaments and the formation of lamellipodia with LamR concentrated at the terminal ends. Cellular fractionation coupled with western blotting illustrated that there was no change in LamR localization or concentration when cells were cultured on laminin, suggesting that the altered immunofluorescence pattern resulted from a redistribution of LamR within the cellular compartments. The additional band in the cytoplasmic fraction likely represents LamR prior to post-translational 9373158 modification, which is important for membrane localization. To study the formation of lamellipodia structures, cells were treated with CB or LamR-specific siRNA to prevent formation of actin filaments and trans
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