In Arabidopsis thaliana, the MEKK1-MKK1/MKK2-MPK4 mitogen-activated protein (MAP) kinase cascade represses cell death and immune responses. In mekk1, mkk1 mkk2, and mpk4 mutants, programmed cell death and defense responses are constitutively activated, but the mechanism by which MEKK1, MKK1/MKK2, and MPK4 negatively regulate cell death and immunity was unknown. From a screen for suppressors of ...

MicroRNAs (miRNAs) are a category of small RNAs that constitute a new layer of complexity to gene regulation within the cell, which has provided new perspectives in understanding cancer biology. The deregulation of miRNAs contributes critically to the development and pathophysiology of a number of cancers. miRNAs have been found to participate in cell transformation and multiplication by acting...

The immune response to beta-galactosidase (beta-D-galactoside galactohydrolase; EC 3.2.1.23)is characterized by a wave of early help followed by a wave of suppression to a subsequent in vitro challenge with galactosidase-fluorescein. A cyanogen bromide peptide of beta-galactosidase, CB2, mimics the suppression seen with the enzyme. It is time dependent, carrier specific, and anti-theta sensitiv...

Periodontitis is a chronic inflammation of periodontal tissue caused by subgingival plaque-associated bacteria. Periodontitis has long been understood to be the result of an excessive host response to plaque bacteria. In addition, periodontal pathogens have been regarded as the causative agents that induce a hyperinflammatory response from the host. In this brief review, host-microbe interactio...

Infection by human coronaviruses is usually characterized by rampant viral replication and severe immunopathology in host cells. Recently, the coronavirus papain-like proteases (PLPs) have been identified as suppressors of the innate immune response. However, the molecular mechanism of this inhibition remains unclear. Here, we provide evidence that PLP2, a catalytic domain of the nonstructural ...

The hallmarks of cancer comprise eight biologic capabilities acquired by incipient cancer cells during the multistep development of human tumors. The hallmarks constitute an organizing principle for rationalizing the complexities of neoplastic disease. They include sustaining proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing an...

BACKGROUND Cytokine profiles of permanent cell lines of head and neck squamous cell carcinoma (HNSCC) were analyzed to define the cytokine levels secreted in the absence of immune cells. MATERIALS AND METHODS Cytokine profiles of IL-4, IL-6, IL-8 and IL-10 were analyzed in the supematants of 4 different permanent HNSCC cell lines using the Bio-Plex human cytokine assay system. RESULTS In HN...

BACKGROUND The Bacillus subtilis genes dnaD and dnaB are essential for the initiation of DNA replication and are required for loading of the replicative helicase at the chromosomal origin of replication oriC. Wild type DnaD and DnaB interact weakly in vitro and this interaction has not been detected in vivo or in yeast two-hybrid assays. METHODOLOGY/PRINCIPAL FINDINGS We isolated second site ...

This report describes the isolation and characterization of second-site suppressors of a cold-sensitive (cs) external scaffolding protein, gpD, of bacteriophage phi X174. Seven genetically distinct suppressors were isolated. Six of them are located in gene F which encodes the major coat protein of the virus. The seventh is located in gene J which encodes the DNA-binding protein. A subset of the...