Dopamine neurotransmission has long been identified as a key component of prefrontal cortical function and flexible cognition; however, flexible behavior does not depend solely on dopamine. Together, multiple systems allow fast and flexible behavior in the face of a constantly changing environment. This Research Topic illuminates work by researchers who are leading efforts to understand how dif...

Genetic deficiency of glycogen synthase kinase-3beta corrects diabetes in mouse models of insulin resistance. Despite treatment with agents that enhance b-cell function and insulin action, reduction in b-cell mass is relentless in patients with insulin resistance and type 2 diabetes mellitus. Insulin resistance is characterized by impaired signaling through the insulin/insulin receptor/insulin ...

Malignancy of cancer has been linked to distinct subsets of stem-like cells, the so-called cancer stem cells (CSCs), which persist during treatment and seem to lead to drug-resistant recurrence. Metastatic spread of cancer cells is one of the hallmarks of malignancy and contributes to most human melanoma-related deaths. Recently, overlapping groups of proteins and pathways were shown to regulat...

In the past, most of the knowledge gained regarding the physiology and the pathology of the pancreas has been evaluated in experimental studies on animals especially on rats/mice. This approach has been criticized in recent years because most of the data obtained from animals cannot be fully applied to humans [1]. A new approach to the physiology and pathology of the pancreas comes from studyin...

The inflammatory response—characterized by release of cytokines such as TNFa and IL-1b and infiltration of infected or injured tissue by macrophages and neutrophils—is the first line of defense against infection by pathogens. Although an early inflammatory response is beneficial in stemming the tide of infection, a prolonged response may result in severe illness or even death. For example, the ...

A fine balance between protein synthesis and protein degradation regulates cellular homeostasis. Cardiac remodelling is a common response of the heart to changes in physiological or pathological demand. Hypertrophic growth is the primary mechanism through which the heart normalizes ventricular wall stress. It is characterized by an increase in the volume of individual cardiac myocytes, which ca...

Shaggy is a downstream component of the wingless and Notch signaling pathways which operate during Drosophila development. To address the role of glycogen synthase kinase 3 beta (GSK3 beta), a mammalian homologue of Shaggy, in vertebrate embryogenesis, it was overexpressed in Xenopus embryos. Microinjection of rat GSK3 beta mRNA into animal ventral blastomeres of 8-cell-stage embryos triggered ...

Naïve or ground state pluripotency is a cellular state in vitro which resembles cells of the preimplantation epiblast in vivo. This state was first observed in mouse embryonic stem cells and is characterized by high rates of proliferation, the ability to differentiate widely, and global hypomethylation. Human pluripotent stem cells (hPSCs) correspond to a later or "primed" stage of embryonic de...

The mechanisms underlying downregulation of the cadherin/catenin complexes and beta-catenin signaling during tumor progression are not fully understood. We have analyzed the effect of oncogenic H-Ras on E-cadherin/catenin complex formation/stabilization and beta-catenin distribution in epidermal keratinocytes. Microinjection or stable expression of V12Ras into keratinocytes promotes the loss of...

We have demonstrated that c-Src suppression inhibited the epithelial to mesenchymal transition in human breast cancer cells. Here, we investigated the role of c-Src on the cell cycle progression using siRNAs and small molecule inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2). Western blot analysis demonstrated the down-regulation of cyclin D1 and cyclin E and up-r...