Air pollutants including diesel exhaust particles (DEPs) have been shown to enhance allergic responses. DEPs stimulate airway epithelial cells to produce various cytokines; however, the intracellular signal transduction pathway and the involvement of reduction and oxidation (redox) control in DEP-activated signaling have not been determined. In the present study, we therefore examined the role ...

The transcription factors Elk-1 and SAP-1 bind together with serum response factor to the serum response element present in the c-fos promoter and mediate increased gene expression. The ERK, JNK, and p38 groups of mitogen-activated protein (MAP) kinases phosphorylate and activate Elk-1 in response to a variety of extracellular stimuli. In contrast, SAP-1 is activated by ERK and p38 MAP kinases ...

Protein kinase C (PKC) regulates activation of the Raf-1 signaling cascade by growth factors, but the mechanism by which this occurs has not been elucidated. Here we report that one mechanism involves dissociation of Raf kinase inhibitory protein (RKIP) from Raf-1. Classic and atypical but not novel PKC isoforms phosphorylate RKIP at serine 153 (Ser-153). RKIP Ser-153 phosphorylation by PKC eit...

SYNOPSIS. Mitogen-activated protein (MAP) kinases constitute a large family of proteins with many functions. They are represented by a multitude of paralogous isoforms in yeast, vertebrates, and other eukaryotes. A phylogenetically conserved function of MAP kinases is to carry osmotic signals from sensory to target elements of cells. Even though this function of MAP kinases is ubiquitous and ch...

Mitogen-activated protein (Map) kinases are widely expressed serine-threonine kinases that mediate important regulatory signals in the cell. Three major groups of Map kinases exist: the p38 Map kinase family, the extracellular signal-regulated kinase (Erk) family, and the c-Jun NH2-terminal kinase (JNK) family. The members of the different Map kinase groups participate in the generation of vari...

long-term potentiation (ltp) is a process that certain types of synaptic stimulation lead to a long-lasting enhancement in the strength of synaptic transmission. studies in recent years indicate the importance of molecular pathways in the development of memory and learning. tropomyosin receptor kinase b (trkb) is a member of the neurotrophin receptor tyrosine kinase family, that its ligand is b...

Cell communication is essential for eukaryotic development, but our knowledge of molecules and mechanisms required for intercellular communication is fragmentary. In particular, the connection between signal sensing and regulation of cell polarity is poorly understood. In the filamentous ascomycete Neurospora crassa, germinating spores mutually attract each other and subsequently fuse. During t...

Stimulating macrophages with bacterial endotoxin (LPS) activates numerous intracellular signaling pathways that lead to the production of TNF. In this study, we show that four mitogen-activated protein (MAP) kinase pathways are activated in LPS-stimulated macrophages: the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase/stress-activated protein kinase, p38, and Big MAP kinas...

MAP kinases p42mapk and p44mapk participate in a protein kinase cascade(s) important for signaling in many cell types and contexts. Both MAP kinases are activated in vitro by MAP kinase kinase, a protein-tyrosine and threonine kinase. A MAP kinase kinase cDNA was isolated from a rat kidney library by using peptide sequence data we obtained from MAP kinase kinase isolated from rabbit skeletal mu...