GHSR in a Subset of GABA Neurons Controls Food Deprivation-Induced Hyperphagia in Male Mice.

The growth hormone secretagogue receptor (GHSR), primarily known as the receptor for the hunger hormone ghrelin, potently controls food intake, yet the specific Ghsr-expressing cells mediating the orexigenic effects of this receptor remain incompletely characterized. Since Ghsr is expressed in gamma-aminobutyric acid (GABA)-producing neurons, we sought to investigate whether the selective expression of Ghsr in a subset of GABA neurons is sufficient to mediate GHSR's effects on feeding. First, we crossed mice that express a tamoxifen-dependent Cre recombinase in the subset of GABA neurons that express glutamic acid decarboxylase 2 (Gad2) enzyme (Gad2-CreER mice) with reporter mice, and found that ghrelin mainly targets a subset of Gad2-expressing neurons located in the hypothalamic arcuate nucleus (ARH) and that is predominantly segregated from Agouti-related protein (AgRP)-expressing neurons.

Pleiotropic Effects of PhaR Regulator in Microaerobic Metabolism.

can live inside soybean root nodules and in free-living conditions. In both states, when oxygen levels decrease, cells adjust their protein pools by gene transcription modulation. PhaR is a transcription factor involved in polyhydroxyalkanoate (PHA) metabolism but also plays a role in the microaerobic network of this bacterium.

Comparative Analysis of Three Bradyrhizobium diazoefficiens Genomes Show Specific Mutations Acquired during Selection for a Higher Motility Phenotype and Adaption to Laboratory Conditions.

Microbial genomes are being extensively studied using next-generation sequencing technologies in order to understand the changes that occur under different selection regimes. In this work, the number and type of mutations that have occurred in three Bradyrhizobium diazoefficiens USDA 110 strains under laboratory conditions and during selection for a more motile phenotypic variant were analyzed. Most of the mutations found in both processes consisted of single nucleotide polymorphisms, single nucleotide deletions or insertions.

A Stringent-Response-Defective Bradyrhizobium diazoefficiens Strain Does Not Activate the Type 3 Secretion System, Elicits an Early Plant Defense Response, and Circumvents NHNO-Induced Inhibition of Nodulation.

When subjected to nutritional stress, bacteria modify their amino acid metabolism and cell division activities by means of the stringent response, which is controlled by the Rsh protein in alphaproteobacteria. An important group of alphaproteobacteria are the rhizobia, which fix atmospheric N in symbiosis with legume plants. Although nutritional stress is common for rhizobia while infecting legume roots, the stringent response has scarcely been studied in this group of soil bacteria.

Dual Control of Flagellar Synthesis and Exopolysaccharide Production by FlbD-FliX Class II Regulatory Proteins in Bradyrhizobium diazoefficiens.

, the N-fixing symbiont of soybean, has two independent flagellar systems: a single subpolar flagellum and several lateral flagella. Each flagellum is a very complex organelle composed of 30 to 40 different proteins located inside and outside the cell whereby flagellar gene expression must be tightly controlled. Such control is achieved by a hierarchy of regulators that ensure the timing of synthesis and the allocation of the different flagellar substructures.