Inhibition of the DevSR Two-Component System by Overexpression of Mycobacterium tuberculosis PknB in Mycobacterium smegmatis.

The DevSR (DosSR) two-component system, which is a major regulatory system involved in oxygen sensing in mycobacteria, plays an important role in hypoxic induction of many genes in mycobacteria. We demonstrated that overexpression of the kinase domain of Mycobacterium tuberculosis (Mtb) PknB inhibited transcriptional activity of the DevR response regulator in Mycobacterium smegmatis and that this inhibitory effect was exerted through phosphorylation of DevR on Thr180 within its DNA-binding domain. Moreover, the purified kinase domain of Mtb PknB significantly phosphorylated RegX3, NarL, KdpE, TrcR, DosR, and MtrA response regulators of Mtb that contain the Thr residues corresponding to Thr180 of DevR in their DNA-binding domains, implying that transcriptional activities of these response regulators might also be inhibited when the kinase domain of PknB is overexpressed.

Changes in the expression of transthyretin and protein kinase Cγ genes in the prefrontal cortex in response to naltrexone.

Naltrexone, an opioid receptor antagonist, has been approved for clinical use in the treatment of alcohol dependence. In the present study, we examined the underlying mechanisms of naltrexone by investigating the pharmacogenomic variations in the brain regions associated with alcohol consumption. A complementary DNA microarray analysis was used to profile gene expression changes in the hippocampus and prefrontal cortex (PFC) of C57BL/6 mice injected with naltrexone following ethanol treatment.

Artificial microRNA-based neurokinin-1 receptor gene silencing reduces alcohol consumption in mice.

In the brain, the stress system plays an important role in motivating continued alcohol use and relapse. The neuropeptide substance P and the neurokinin-1 receptor (NK1R) are involved in the stress response and drug reward systems. Recent findings have shown that the binding of ligands to NK1Rs decreases the self-administration of alcohol in mice.