Multiplexing the Quantitation of MAP Kinase Activities Using Differential Sensing.

Protein kinases are therapeutic targets for many human diseases, but the lack of user-friendly quantitative assays limits the ability to follow the activities of numerous kinases at once (multiplexing). To develop such an assay, we report an array of sulfonamido-oxine (SOX)-labeled peptides showing cross-reactivity to different mitogen-activated protein kinases (MAPKs) for use in a differential sensing scheme. We first verified using linear discriminant analysis that the array could differentiate MAPK isoforms.

Combination of two analytical techniques improves wine classification by Vineyard, Region, and vintage.

Three important wine parameters: vineyard, region, and vintage year, were evaluated using fifteen Vitis vinifera L. 'Pinot noir' wines derived from the same scion clone (Pinot noir 667). These wines were produced from two vintage years (2015 and 2016) and eight different regions along the Pacific Coast of the United States.

Quantification of ERK Kinase Activity in Biological Samples Using Differential Sensing.

The understanding of complex biological systems requires an ability to evaluate interacting networks of genes, proteins, and cellular reactions. Enabling technologies that support the rapid quantification of these networks will facilitate the development of biological models and help to identify treatment targets and to assess treatment plans. The biochemical process of protein phosphorylation, which underlies almost all aspects of cell signaling, is typically evaluated by immunoblotting procedures (Western blot) or more recently proteomics procedures, which provide qualitative estimates of the concentration of proteins and their modifications in cells.

Modulating multi-functional ERK complexes by covalent targeting of a recruitment site in vivo.

Recently, the targeting of ERK with ATP-competitive inhibitors has emerged as a potential clinical strategy to overcome acquired resistance to BRAF and MEK inhibitor combination therapies. In this study, we investigate an alternative strategy of targeting the D-recruitment site (DRS) of ERK. The DRS is a conserved region that lies distal to the active site and mediates ERK-protein interactions.

A Novel Class of Common Docking Domain Inhibitors That Prevent ERK2 Activation and Substrate Phosphorylation.

Extracellular signal-regulated kinases (ERK1/2) are mitogen-activated protein kinases (MAPKs) that play a pro-tumorigenic role in numerous cancers. ERK1/2 possess two protein-docking sites that are distinct from the active site: the D-recruitment site (DRS) and the F-recruitment site. These docking sites facilitate substrate recognition, intracellular localization, signaling specificity, and protein complex assembly.

Differential sensing of MAP kinases using SOX-peptides.

Five SOX peptides are used to classify the MAPK groups and isoforms thereof using chemometrics. The score plots show excellent classification and accuracy, while support vector machine analysis leads to the quantification of ERK and an ERK inhibitor concentration in kinase mixtures. Examination of the loading plots reveals cross-reactivity among the peptides, and some unexpected surprises.

In-situ generation of differential sensors that fingerprint kinases and the cellular response to their expression.

Mitogen-activated protein (MAP) kinases are responsible for many cellular functions, and their malfunction manifests itself in several human diseases. Usually, monitoring the phosphorylation states of MAP kinases in vitro requires the preparation and purification of the proteins or Western blotting. Herein, we report an array sensing approach for the differentiation of MAP kinases and their phosphorylated counterparts in vitro.