DNA methylation is a key epigenetic mark when occurring in the promoter and enhancer regions regulates the accessibility of the binding protein and gene transcription. DNA methylation is inheritable and can be
The success of many enteric bacteria is hinged on the ability to tolerate environmental stress such as extreme acidity. The acid stress response (ASR) has been investigated in many enteric bacteria and has been shown to involve variable expression of a broad spectrum of genes involved in transcriptional regulation, metabolism, colonization and virulence; representing a linkage between acid tolerance and pathogenicity. Though the majority of ASR studies have been conducted in laboratory conditions and from the perspective of pathogenicity, the role of environmental reservoirs on acid adaptation has recently emerged as an important aspect of pathogenic microbial ecology. This mini-review profiles ASR in three opportunistic enteric pathogens and synthesizes recent work pertaining to the study of this dynamic response.
Chronic obstructive pulmonary disease (COPD) is a highly relevant disorder that induces respiratory muscle dysfunction. One prevalent symptom of COPD is resistive breathing which causes respiratory muscle to significantly increase the magnitude of contractions, resulting in reactive oxygen species (ROS) formation and oxidative stress. Through cellular signaling cascades, ROS activate molecules such as mitogen-activated protein kinases and nuclear factor-κB. These signaling molecules stimulate the release of cytokines which in turn cause damage to the diaphragm, involving sarcomeric disruptions. In response to COPD induced fatigue, the diaphragm undergoes a beneficial fiber-type shift to type I muscle fibers, which are more resistant to hypoxia than type II fibers. The lung hyperinflation that occurs in COPD also causes intercostal muscle dysfunction, thereby exacerbating COPD symptoms. In addition, COPD is known to have a connection with heart failure, diabetes, and aging, further decreasing respiratory function. Currently, there is no cure for this disorder. Nevertheless, various potential therapeutic strategies focusing on respiratory muscle have been identified including respiratory muscle training, β2-agonist therapy, and lung volume reduction surgery. In this review, we will outline the role of COPD, oxidative stress, and related complications in respiratory muscle dysfunction.
The phospholipase A2 (PLA2) family members are critical regulators of membrane structure and lipid composition and have been implicated in neuroinflammation, oxidative stress and neurodegeneration. Here, we review the published data describing regulation of cPLA2 and iPLA2 gene expression. Based on promoter sequence, cPLA2 expression can be regulated by glucocorticoid and pro-inflammatory cytokines, whereas transcription of iPLA2 can be controlled in response to sterol level. RNA degradation in 3′ UTR and epigenetic mechanisms may be involved in the regulation of cPLA2 and iPLA2 expression, respectively. MicroRNA target sequences lie within cPLA2 and iPLA2 mRNAs. Together, these findings indicate differential regulation of cPLA2 and iPLA2 expression. It is hoped that determination of diverse regulatory mechanisms of the PLA2 family may open new doors for development of novel therapeutic compounds that modulate PLA2 expression and function in the treatment of brain diseases.
The Murphy Roths Large (MRL/MpJ) mice provide unique insights into wound repair and regeneration. These mice and the closely related MRL/MpJ-
Currently, single-cell C4 photosynthesis has been reported in four terrestrial plant species,
Carbon (C) and nitrogen (N) are two essential nutrients affecting plant growth and development. Plants are non-motile organisms and have evolved highly sophisticated and complex sensing and signaling mechanisms to respond to the dynamic changes of C and N nutrients in their surroundings. C and N metabolism are tightly coordinated to maintain intracellular C/N homeostasis. However, the regulatory mechanism underlying C/N coordination and balancing in plants remains to be elucidated. It has been suggested that C and N metabolism are modulated by the interaction of C signaling with N signaling or by C/N ratio signaling. This review focuses on cell signaling studies that provide insight into the regulation mechanism of C/N balancing in plants.
Phosphorylation is one of the most common post translational modifications (PTM), participating in a large number of processes to regulate cellular functions. Phosphorylation is also one of the key factors in the origin and development of cancer. The rapid development of mass spectrometric-based phosphoproteomic technologies has made it possible for high-throughput identification and quantification of phosphorylation events. In this review, we provide a general introduction and summary of the achievements made in mass spectrometry based phosphoproteomic research, including the approaches for phosphopeptide identification and quantification, as well as instrumentation and data interpretation methods. We also review some discoveries in cancer research made possible by phosphoproteomic analysis technologies.
Throughout the animal kingdom, Wnt-triggered signal transduction pathways play fundamental roles in embryonic development and tissue homeostasis. Wnt proteins are modified as glycolipoproteins and are secreted into the extracellular environment as morphogens. Recent studies on the intracellular trafficking of Wnt proteins demonstrate multiple layers of regulation along its secretory pathway. These findings have propelled a great deal of interest among researchers to further investigate the molecular mechanisms that control the release of Wnts and hence the level of Wnt signaling. This review is dedicated to Wntless, a putative G-protein coupled receptor that transports Wnts intracellularly for secretion. Here, we highlight the conclusions drawn from the most recent cellular, molecular and genetic studies that affirm the role of Wntless in the secretion of Wnt proteins.