First Author | Diakonova M | Year | 2007 |
Journal | Infect Immun | Volume | 75 |
Issue | 7 | Pages | 3581-93 |
PubMed ID | 17452473 | Mgi Jnum | J:122422 |
Mgi Id | MGI:3714256 | Doi | 10.1128/IAI.00214-07 |
Citation | Diakonova M, et al. (2007) Adapter Protein SH2-B{beta} Stimulates Actin-Based Motility of Listeria monocytogenes in a Vasodilator-Stimulated Phosphoprotein (VASP)-Dependent Fashion. Infect Immun 75(7):3581-93 |
abstractText | SH2-Bbeta (Src homology 2 Bbeta) is an adapter protein that is required for maximal growth hormone-dependent actin reorganization in membrane ruffling and cell motility. Here we show that SH2-Bbeta is also required for maximal actin-based motility of Listeria monocytogenes. SH2-Bbeta localizes to Listeria-induced actin tails and increases the rate of bacterial propulsion in infected cells and in cell extracts. Furthermore, Listeria motility is decreased in mouse embryo fibroblasts from SH2-B(-/-) mice. Both recruitment of SH2-Bbeta to Listeria and SH2-Bbeta stimulation of actin-based propulsion require the vasodilator-stimulated phosphoprotein (VASP), which binds ActA at the surfaces of Listeria cells and enhances bacterial actin-based motility. SH2-Bbeta enhances actin-based movement of ActA-coated beads in a biomimetic actin-based motility assay, provided that VASP is present. In vitro binding assays show that SH2-Bbeta binds ActA but not VASP; however, binding to ActA is greater in the presence of VASP. Because VASP also plays an essential regulatory role in actin-based processes in eukaryotic cells, the present results provide mechanistic insight into the functions of both SH2-Bbeta and VASP in motility and also increase our understanding of the fundamental mechanism by which Listeria spreads. |