Differential functions of WAVE regulatory complex subunits in the regulation of actin-driven processes.

The WAVE regulatory complex (WRC) links upstream Rho-family GTPase signaling to the activation of the ARP2/3 complex in different organisms. WRC-induced and ARP2/3 complex-mediated actin nucleation beneath the plasma membrane is critical for actin assembly in the leading edge to drive efficient cell migration. The WRC is a stable heteropentamer composed of SCAR/WAVE, Abi, Nap, Pir and the small polypeptide Brk1/Hspc300.

First insight into the kinome of human regulatory T cells.

Regulatory T cells (Tregs) are essential for controlling peripheral tolerance by the active suppression of various immune cells including conventional T effector cells (Teffs). Downstream of the T cell receptor (TCR), more than 500 protein kinases encoded by the human genome have to be considered in signaling cascades regulating the activation of Tregs and Teffs, respectively. Following TCR engagement, Tregs posses a number of unique attributes, such as constitutive expression of Foxp3, hyporesponsiveness and poor cytokine production.

High-resolution mass spectrometric analysis of the secretome from mouse lung endothelial progenitor cells.

Recently, we isolated and characterized resident endothelial progenitor cells from the lungs of adult mice. These cells have a high proliferation potential, are not transformed and can differentiate into blood- and lymph-vascular endothelial cells under in vitro and in vivo conditions. Here we studied the secretome of these cells by nanoflow liquid chromatographic mass spectrometry (LC-MS).

Quantitative phosphokinome analysis of the Met pathway activated by the invasin internalin B from Listeria monocytogenes.

Stimulated by its physiological ligand, hepatocyte growth factor, the transmembrane receptor tyrosine kinase Met activates a signaling machinery that leads to mitogenic, motogenic, and morphogenic responses. Remarkably, the food-borne human pathogen Listeria monocytogenes also promotes autophosphorylation of Met through its virulence factor internalin B (InlB) and subsequently exploits Met signaling to induce phagocytosis into a broad range of host cells. Although the interaction between InlB and Met has been studied in detail, the signaling specificity of components involved in InlB-triggered cellular responses remains poorly characterized.

Direct mass spectrometric peptide profiling and fragmentation of larval peptide hormone release sites in Drosophila melanogaster reveals tagma-specific peptide expression and differential processing.

Regulatory peptides represent a diverse group of messenger molecules. In insects, they are produced by endocrine cells as well as secretory neurones within the CNS. Many regulatory peptides are released as hormones into the haemolymph to regulate, for example, diuresis, heartbeat or ecdysis behaviour.