Discipline: Biological Sciences
Subcategory: Cell and Molecular Biology
Julian Dill - Lawson State Community College
Co-Author(s): Yuhau Song and Justin Howell, University of Birmingham, AL
Cell adhesion is the binding of a cell to either another cell or a surface such as a matrix. Anchor dependent cells such as endothelial and fibroblasts rely on focal adhesions for survival and migration. Adhesion is controlled by the cell surface proteins that are essential in the adhesion of cells for maintaining a structure suitable for proper function. In this study we are interested in the thrombospondin (TSP1) induced binding between Calreticulin (CRT) and low density lipoprotein receptor related protein1 (LRP1). CRT on the cell surface involves focal adhesion disassembly, cell migration, phagocytosis, and immune regulation. Cell surface CRT regulation of focal adhesion disassembly requires TSP1-CRTLRP1 ternary complex formation. Calreticulin has three domains: the N-domain, P-domain, and the C-domain. The CRT binding site in TSP1 has been localized to amino acids 17−35 in CRT Ndomain. The binding site of LRP1 in CRT is still unknown. The LRP1 binding site on CRT could be located on an otherwise hidden site in CRT, which could be exposed by CRT bound to TSP1. The goal of this study is determine the LRP1 binding site in TSP1-bound CRT. The results will help to understand the TSP1induced CRT-LRP1 binding towards the tertiary complex formation in cell focal adhesion disassembly and anoikis resistance. The TSP1-induced CRT-LRP1 interactions in mouse embryonic fibroblast cells (MEF) will be determined using protein complex immunoprecipitation (co-IP) experiments and evaluated using western blotting analysis.
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Funder Acknowledgement(s): This study was supported, in part, by a grant from NSF awarded to Michael J. Wyss, PhD, Director of Blazing Bio-medical Careers, University of Birmingham, AL 35294. Yuhua, Song, PhD, Associate Professor, Dept. of Biomedical Engineering, The University of Alabama at Birmingham, Shelby.
Faculty Advisor: Yuhau Song,