Volumetric absorptive microsampling as an effective microsampling technique for LC-MS/MS bioanalysis of biomarkers in drug discovery.

Develop and validate a volumetric absorptive microsampling (VAMS)-based LC-MS/MS method to support the bioanalysis of amino acid and carboxylic acid biomarkers in mouse whole blood. Mouse whole blood was collected using a 10 μl VAMS device. The analytes in VAMS were extracted and analyzed using an LC-MS/MS method.

23814, an Inhibitory Antibody of Ligand-Mediated Notch1 Activation, Modulates Angiogenesis and Inhibits Tumor Growth without Gastrointestinal Toxicity.

Dysregulation of Notch signaling has been implicated in the development of many different types of cancer. Notch inhibitors are being tested in the clinic, but in most cases gastrointestinal and other toxicities have limited the dosage and, therefore, the effectiveness of these therapies. Herein, we describe the generation of a monoclonal antibody against the ligand-binding domain of the Notch1 receptor that specifically blocks ligand-induced activation.

A genome-wide Drosophila RNAi screen identifies DYRK-family kinases as regulators of NFAT.

Precise regulation of the NFAT (nuclear factor of activated T cells) family of transcription factors (NFAT1-4) is essential for vertebrate development and function. In resting cells, NFAT proteins are heavily phosphorylated and reside in the cytoplasm; in cells exposed to stimuli that raise intracellular free Ca2+ levels, they are dephosphorylated by the calmodulin-dependent phosphatase calcineurin and translocate to the nucleus. NFAT dephosphorylation by calcineurin is countered by distinct NFAT kinases, among them casein kinase 1 (CK1) and glycogen synthase kinase 3 (GSK3).

A dual-kinase mechanism for Wnt co-receptor phosphorylation and activation.

Signalling by the Wnt family of secreted lipoproteins has essential functions in development and disease. The canonical Wnt/beta-catenin pathway requires a single-span transmembrane receptor, low-density lipoprotein (LDL)-receptor-related protein 6 (LRP6), whose phosphorylation at multiple PPPSP motifs is induced upon stimulation by Wnt and is critical for signal transduction. The kinase responsible for LRP6 phosphorylation has not been identified.

A conserved docking motif for CK1 binding controls the nuclear localization of NFAT1.

In resting cells, the NFAT1 transcription factor is kept inactive in the cytoplasm by phosphorylation on multiple serine residues. These phosphorylated residues are primarily contained within two types of serine-rich motifs, the SRR-1 and SP motifs, which are conserved within the NFAT family. Several different kinases have been proposed to regulate NFAT, but no single candidate displays the specificity required to fully phosphorylate both types of motifs; thus, the identity of the kinase that regulates NFAT activity remains unclear.

Ca2+/calcineurin signalling in cells of the immune system.

Calcineurin is a serine-threonine - phosphatase that is expressed in a wide variety of tissues and has particularly critical functions in neurons, cardiac and skeletal muscle cells, and lymphocytes. This review focuses on recent studies elucidating the role of Ca(2+)/calcineurin signalling of the immune system.