The ability of a pathogen to cause infection depends on successful colonization of the host, which, in turn, requires adaptation to various challenges presented by that host. For example, host immune cells use a variety of mechanisms to control infection by bacterial pathogens, including the production of bactericidal reactive oxygen species. Prokaryotic and eukaryotic cells have developed ways...

PURPOSE c-Met is a receptor tyrosine kinase involved in cell growth, invasion, metastases, and angiogenesis. In this study, we investigated the role of c-Met in melanoma biology using a novel small-molecule tyrosine kinase inhibitor SU11274 and small interfering (si) RNA against the receptor. EXPERIMENTAL DESIGN The effects of SU11274 and c-Met siRNA were studied on proliferation, apoptosis, ...

Necrostatin-1 (Nec-1) inhibits necroptosis by allosterically inhibiting the kinase activity of receptor-interacting protein 1 (RIP1), which plays a critical role in necroptosis. RIP1 is a crucial adaptor kinase involved in the activation of NF-κB, production of reactive oxygen species (ROS) and the phosphorylation of mitogen activated protein kinases (MAPKs). NF-κB, ROS and MAPKs all play impor...

IFN regulatory factor (IRF) 3 participates in the transcriptional induction of IFN-alpha, IFN-beta, and a subset of IFN-stimulated genes (ISGs) as a result of viral infection. In addition, bacterial cell wall components such as LPS activate IRF3 in a p38-dependent manner. In this study we show that IRF3-mediated ISG induction by LPS requires the production of reactive oxygen species (ROS) by th...

The regulating mechanism of miRNA on p53 dynamics in p53−MDM2−miRNA model network incorporating reactive oxygen species (ROS) is studied. The study shows that miRNA drives p53 dynamics at various states, namely, stabilized states and oscillating states (damped and sustain oscillation). We found the co-existence of these states within certain range of the concentartion level of miRNA in the syst...

Although historically reactive oxygen species have been implicated as a potential cause of ageing, recent evidence suggests that a modest increase in oxidants can actually extend lifespan. A new study suggests that, in Caenorhabditis elegans, reactive oxygen species regulate longevity through a pathway classically linked to apoptosis.

JSAP1 (also termed JIP3) is a scaffold protein that interacts with specific components of the JNK signaling pathway. Apoptosis signal-regulating kinase (ASK) 1 is a MAP kinase kinase kinase that activates the JNK and p38 mitogen-activated protein (MAP) kinase cascades in response to environmental stresses such as reactive oxygen species. Here we show that JSAP1 bound ASK1 and enhanced ASK1- and...

Kazrin has recently been identified as a functional protein that is involved in cell-cell junctions and in signal transduction. Here, we identified a new isoform, Kazrin F, which is 518 aa in length and has 97 aa unique at the N-terminus. Knockdown of Kazrin F using siRNA caused cell apoptosis and a marked decrease in cell viability measured by MTT and TUNEL assays. Co-immunoprecipitation analy...

Ultraviolet (UV) radiation and reactive oxygen species (ROS) impair the physiological functions of retinal pigment epithelium (RPE) cells by inducing cell apoptosis, which is the main cause of age-related macular degeneration (AMD). The mechanism by which UV/ROS induces RPE cell death is not fully addressed. Here, we observed the activation of a ceramide-endoplasmic reticulum (ER) stress-AMP ac...

abstract accumulation of gene changes and chromosomal instability in response to cellular dna damage lead to cancer. dna damage induces cell cycle checkpoints pathways. checkpoints regulate dna replication and cell cycle progression, chromatin restructuring, and apoptosis. checkpoint kinase 2 (chk2) is activated in response to dna lesions. atm phosphorylate chk2. the activated chk2 kinase can p...