Theranostics 2016; 6(12):2129-2140. doi:10.7150/thno.16356 This issue Cite
Research Paper
1. State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China.
2. Institute of Biomedical Sciences, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Key Laboratory of Molecular and Nano Probes of the Ministry of Education, Shandong Normal University, Jinan 250014, China.
Cell migration, a complex process critical for tumor progression and metastasis, requires a dynamic crosstalk between microtubules (MTs) and focal adhesions (FAs). However, the molecular mechanisms underlying this event remain elusive. Herein we identify the proto-oncogenic protein Src as an important player in the regulation of the MT-FA crosstalk. Src interacts with and phosphorylates end-binding protein 1 (EB1), a member of MT plus end-tracking proteins (+TIPs), both in cells and in vitro. Systematic mutagenesis reveals that tyrosine-247 (Y247) is the primary residue of EB1 phosphorylated by Src. Interestingly, both constitutively activated Src and Y247-phosphorylated EB1 localize to the centrosome and FAs. Src-mediated EB1 phosphorylation diminishes its interactions with other +TIPs, including adenomatous polyposis coli (APC) and mitotic centromere associated kinesin (MCAK). In addition, EB1 phosphorylation at Y247 enhances the rate of MT catastrophe and significantly stimulates cell migration. These findings thus demonstrate that the Src-EB1 axis plays a crucial role in regulating the crosstalk between MTs and FAs to promote cell migration.
Keywords: EB1, Src, phosphorylation, microtubule, focal adhesion, cell migration.