Roles of microfilaments and microtubules in paxillin dynamics

• Published in: Biochemical and biophysical research communications Vol. 348; no. 4; pp. 1463 - 1471
• Main Authors: Hu, Ying-Li, Haga, Jason H., Miao, Hui, Wang, Yingxiao, Li, Yi-Shuan, Chien, Shu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 06-10-2006
• Subjects: Actin Cytoskeleton - drug effects; Actin Cytoskeleton - physiology; Actin Cytoskeleton - ultrastructure; Actin filaments; Animals; Cattle; Cell Movement; Cells, Cultured; Colchicine - pharmacology; Cytochalasin D; Cytochalasin D - pharmacology; Endothelium, Vascular - metabolism; Endothelium, Vascular - physiology; Endothelium, Vascular - ultrastructure; Focal adhesion; Focal Adhesions; Microtubules - drug effects; Microtubules - physiology; Microtubules - ultrastructure; Migration; Paclitaxel - pharmacology; Paxillin - analysis; Paxillin - chemistry; Paxillin - metabolism; Phosphorylation; Tubulin Modulators - pharmacology; Tyrosine - metabolism; Cytochalasin D; Actin filaments; Migration; Focal adhesion
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1016/j.bbrc.2006.08.022

We investigated the roles of microfilaments and microtubules in the localization and tyrosine phosphorylation of paxillin, a focal adhesion-associated signaling molecule, in bovine aortic endothelial cells (BAECs). Paxillin tyrosine phosphorylation is inhibited by cytochalasin D (CD), but slightly increased by colchicine and paclitaxol (taxol). CD also caused an overall disassembly of paxillin-containing focal adhesions (paxillin-FAs) and translocation of paxillin to the cytoplasm and perinuclear region with a diffuse distribution. Meanwhile, colchicine and taxol caused a disassembly of paxillin-FAs from cell periphery and lamellipodia, and their assembly in cell center. These results indicate that actin filaments are important in paxillin assembly in the FAs of the whole ECs and that microtubules are critical in paxillin assembly in cell periphery and lamellipodia; thus the microfilaments and microtubules play differential roles in the dynamics of paxillin assembly/disassembly. Our findings also suggest that tyrosine phosphorylation is an important element in paxillin dynamics at FAs.