Unlike other members of the MAPK family, ERK5 contains a large C-terminal domain with transcriptional activation capability in addition to an N-terminal canonical kinase domain. Genetic deletion of ERK5 is embryonic lethal, and tissue-restricted deletions have profound effects on erythroid development, cardiac function, and neurogenesis. In addition, depletion of ERK5 is antiinflammatory and antitumorigenic.
View Article and Find Full Text PDFPalbociclib is a cyclin-dependent kinase (CDK) 4/CDK6 inhibitor approved for breast cancer that is estrogen receptor (ER)-positive and human epidermal growth factor receptor 2 (HER2)-negative. We profiled palbociclib in cells either sensitive or resistant to the drug using an ATP/ADP probe-based chemoproteomics platform. Palbociclib only engaged CDK4 or CDK6 in sensitive cells.
View Article and Find Full Text PDFWe describe the identification of a novel, tumor-specific missense mutation in the active site of casein kinase 1α (CSNK1A1) using activity-based proteomics. Matched normal and tumor colon samples were analyzed using an ATP acyl phosphate probe in a kinase-targeted LC-MS2 platform. An anomaly in the active-site peptide from CSNK1A1 was observed in a tumor sample that was consistent with an altered catalytic aspartic acid.
View Article and Find Full Text PDFBackground: Neutrophil elastase (NE) rapidly degrades gel-forming airway mucins in cystic fibrosis (CF) sputum. We hypothesized that KRP-109, a small molecule NE inhibitor, would inhibit CF mucin degradation in vitro.
Methods: Sputa were collected from CF patients (n=5) chronically or intermittently infected with Pseudomonas aeruginosa (P.
Introduction: Ultrasound and electric stimulation are known therapies for the treatment of chronic ulcerations. Combined modulated ultrasound and electric field stimulation (CUSEFS) have never been studied as a single modality. The authors evaluate the results of CUSEFS (BRH Medical Ltd, Jerusalem, Israel) on a variety of wound types in a number of clinics.
View Article and Find Full Text PDFIntroduction: Charcot neuroarthropathy may occur in patients with peripheral neuropathy who do not notice pain while their bones and joints collapse or breakdown under the constant pressure of body weight. This can lead to ulcerations from severe deformity and potentially limb-threatening and life-threatening infections. Current treatments vary from immobilization to extensive reconstructive surgical interventions.
View Article and Find Full Text PDFHsp90 is an ATP-dependent chaperone of widespread interest as a drug target. Here, using an LC-MS/MS chemoproteomics platform based on a lysine-reactive ATP acyl phosphate probe, several Hsp90 inhibitors were profiled in native cell lysates. Inhibitor specificities for all four human paralogs of Hsp90 were simultaneously monitored at their endogenous relative abundances.
View Article and Find Full Text PDFIntroduction: Transcutaneous oxygen pressure (TcPO2) less than 30 mm Hg at the toe leads to local tissue hypoxia and nonhealing wounds. Studies regularly illustrate that TcPO2 values are strong predictors of healing and can accurately demonstrate altered levels when extremities have restricted blood flow. The objective of this study was to evaluate the effectiveness of surface acoustic wave (SAW) in ischemic feet on local tissue oxygenation.
View Article and Find Full Text PDFHere we describe a chemical proteomics strategy using ATP acyl phosphates to measure the formation of a protein:protein complex between p38α and mapkap kinases 2 and/or 3. Formation of the protein:protein complex results in a new probe labeling site on p38α that can be used to quantify the extent of interaction in cell lysates and the equilibrium binding constant for the interaction in vitro. We demonstrate through RNA interference that the labeling site is dependent on formation of the protein:protein complex in cells.
View Article and Find Full Text PDFDipeptidyl peptidases (DPPs) are proteolytic enzymes that regulate many physiological systems by degrading signaling peptides. DPP8 and DPP9 are distinct from DPP4 in sequence, cellular localization and expression levels, thus implying distinct functions. However, DPP8 and DPP9 expression needs further delineation.
View Article and Find Full Text PDFThe largest mammalian enzyme family is the kinases. Kinases and other nucleotide-binding proteins are key regulators of signal transduction pathways and the mutation or overexpression of these proteins is often the difference between health and disease. As a result, a massive research effort has focused on understanding how these proteins function and how to inhibit them for therapeutic benefit.
View Article and Find Full Text PDFKIAA1363 is a serine hydrolase whose activity has been shown to be positively associated with tumor cell invasiveness. Thus, inhibitors of KIAA1363 represent a novel targeted therapy approach towards cancer. AX11890 ((1-bromo-2-naphthyl) N,N-dimethylcarbamate) was identified as a KIAA1363 inhibitor with an IC(50) value of 1.
View Article and Find Full Text PDFThe synthesis, GSK-3β inhibitory activity, and anti-microbial activity of bicyclic and tricyclic derivatives of the 5,7-diamino-6-fluoro-4-quinolone-3-carboxylic acid scaffold were studied. Kinase selectivity profiling indicated that members of this class were potent and highly selective GSK-3 inhibitors.
View Article and Find Full Text PDFThe Karyopherin (Kap) family of nuclear transport receptors enables trafficking of proteins to and from the nucleus in a precise, regulated manner. Individual members function in overlapping pathways, while simultaneously being very specific for their main cargoes. The details of this apparent contradiction and rules governing pathway preference remain to be further elucidated.
View Article and Find Full Text PDFBackground: In spite of recent advances in post-operative pain relief, pain following orthopedic surgery remains an ongoing challenge for clinicians. We examined whether a well known and frequently prescribed homeopathic preparation could mitigate post-operative pain.
Method: We performed a randomized, double blind, placebo-controlled trial to evaluate the efficacy of the homeopathic preparation Traumeel S in minimizing post-operative pain and analgesic consumption following surgical correction of hallux valgus.
Introduction: Increase of serum alanine aminotransferase (ALT) activity is widely used as a surrogate marker for tissue damage. Two ALT isoforms, ALT1 and ALT2, have been cloned recently in mammals. The study investigated the source of elevated ALT activity in serum of dogs treated with a hepatotoxic compound.
View Article and Find Full Text PDFPolo-like kinases play crucial roles throughout mitosis. We previously reported that wortmannin potently inhibits Polo-like kinase 1 (Plk1). In this study, we show that wortmannin also strongly inhibits Polo-like kinase 3 (Plk3).
View Article and Find Full Text PDFA cell permeable DPP II [also known as DPP2, DPP7, and quiescent cell proline dipeptidase (QPP)] inhibitor has been synthesized. The azabicyclo[3.3.
View Article and Find Full Text PDFThe structure-activity relationship of various N-alkyl Gly-boro-Pro derivatives against three dipeptidyl peptidases (DPPs) was studied. In a series of N-cycloalkyl analogs, DPP4 and fibroblast activation protein-alpha (FAP) optimally preferred N-cycloheptyl whereas DPP7 tolerated even larger cycloalkyl rings. Gly alpha-carbon derivatization of N-cyclohexyl or N-(2-adamantyl) Gly-boro-Pro resulted in a significant decrease in potency against all the three DPPs.
View Article and Find Full Text PDFDipeptide-based inhibitors with C-substituted (alkyl or aminoalkyl) alpha-amino acids in the P2 position and boro-norleucine (boro-Nle) in the P1 position were synthesized. Relative to boro-proline, boro-Nle as a P1 residue was shown able to significantly dial out DPP4, FAP, DPP8, and DPP9 activity. Dab-boro-Nle (4g) proved to be the most selective and potent DPP7 inhibitor with a DPP7 IC50 value of 480 pM.
View Article and Find Full Text PDFPolo-like kinases (PLKs) play critical roles throughout mitosis. Here, we report that wortmannin, which was previously thought to be a highly selective inhibitor of phosphoinositide (PI) 3-kinases, is a potent inhibitor of mammalian PLK1. Observation of the wortmannin-PLK1 interaction was enabled by a tetramethylrhodamine-wortmannin conjugate (AX7503) that permits rapid detection of PLK1 activity and expression in complex proteomes.
View Article and Find Full Text PDFAssay Drug Dev Technol
February 2003
In the latter stages of drug discovery and development, assays that establish drug selectivity and toxicity are important when side effects, which are often due to lack of specificity, determine drug candidate viability. There has been no comprehensive or systematic methodology to measure these factors outside of whole-animal assays, and such phenomenological assays generally fail to establish the additional targets of a given small molecule, or the molecular origin of toxicity. Consequently, small-molecule development programs destined for failure often reach advanced stages of testing, and the money and time invested in such programs could be saved if information on selectivity were available early in the process.
View Article and Find Full Text PDFAn analysis of the structurally and catalytically diverse serine hydrolase protein family in the Saccharomyces cerevisiae proteome was undertaken using two independent but complementary, large-scale approaches. The first approach is based on computational analysis of serine hydrolase active site structures; the second utilizes the chemical reactivity of the serine hydrolase active site in complex mixtures. These proteomics approaches share the ability to fractionate the complex proteome into functional subsets.
View Article and Find Full Text PDFCurr Opin Chem Biol
August 2003
Much attention has recently been given to a class of proteases that cleave proteins and peptides after proline residues. This class includes dipeptidyl peptidase IV (DPP IV; also termed CD26), fibroblast activation protein alpha (FAP; seprase), DPP7 (DPP II; quiescent cell proline dipeptidase), DPP8, DPP9, and prolyl carboxypeptidase (PCP; angiotensinase C). More distant members include prolyl oligopeptidase (POP; post proline cleaving enzyme) and acylaminoacylpeptidase (AAP; acylpeptide hydrolase).
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