Dataset Information

Npr2 inhibits TORC1 to prevent inappropriate utilization of glutamine for biosynthesis of nitrogen-containing metabolites.

ABSTRACT: Cells must be capable of switching between growth and autophagy in unpredictable nutrient environments. The conserved Npr2 protein complex (comprising Iml1, Npr2, and Npr3; also called SEACIT) inhibits target of rapamycin complex 1 (TORC1) kinase signaling, which inhibits autophagy in nutrient-rich conditions. In yeast cultured in media with nutrient limitations that promote autophagy and inhibit growth, loss of Npr2 enables cells to bypass autophagy and proliferate. We determined that Npr2-deficient yeast had a metabolic state distinct from that of wild-type yeast when grown in minimal media containing ammonium as a nitrogen source and a nonfermentable carbon source (lactate). Unlike wild-type yeast, which accumulated glutamine, Npr2-deficient yeast metabolized glutamine into nitrogen-containing metabolites and maintained a high concentration of S-adenosyl methionine (SAM). Moreover, in wild-type yeast grown in these nutrient-limited conditions, supplementation with methionine stimulated glutamine consumption for synthesis of nitrogenous metabolites, demonstrating integration of a sulfur-containing amino acid cue and nitrogen utilization. These data revealed the metabolic basis by which the Npr2 complex regulates cellular homeostasis and demonstrated a key function for TORC1 in regulating the synthesis and utilization of glutamine as a nitrogen source.

SUBMITTER: Laxman S

PROVIDER: S-EPMC4427238 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Npr2 inhibits TORC1 to prevent inappropriate utilization of glutamine for biosynthesis of nitrogen-containing metabolites.

Laxman Sunil S Sutter Benjamin M BM Shi Lei L Tu Benjamin P BP

Science signaling 20141216 356

Cells must be capable of switching between growth and autophagy in unpredictable nutrient environments. The conserved Npr2 protein complex (comprising Iml1, Npr2, and Npr3; also called SEACIT) inhibits target of rapamycin complex 1 (TORC1) kinase signaling, which inhibits autophagy in nutrient-rich conditions. In yeast cultured in media with nutrient limitations that promote autophagy and inhibit growth, loss of Npr2 enables cells to bypass autophagy and proliferate. We determined that Npr2-defi ...[more]

PMID: 25515537

Similar Datasets

Project description:ObjectiveMost exacerbations are mild to moderate, and antibiotic treatment for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is recommended for patients with severe exacerbations or severe underlying chronic obstructive pulmonary disease (COPD). Therefore, we aimed to investigate the patient factors that are associated with the prescription of antibiotics for inappropriate indication in AECOPD.Material and methodsThis study was an observational cross-sectional study conducted in an outpatient clinic. The patients diagnosed with AECOPD and prescribed an antibiotic by a pulmonary physician were enrolled in the study. These prescriptions were documented by the pharmacist who asked the patient about the three cardinal symptoms. Appropriate and inappropriate prescription groups were defined by the types of exacerbations, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) COPD report.ResultsThere were 138 patients, predominantly male (83%), with a mean age of 64 (±9) years. A total of 64% of the prescriptions were appropriate; however, there were 50 (36%) patients with inappropriate antibiotic prescription according to the mentioned criteria. When we compared the patient factors between the appropriate and inappropriate antibiotic prescriptions, there was no statistically significant difference in terms of age, Forced expiratory volume in first second % (FEV1%) predicted, FEV1 ml, forced vital capacity (FVC) ml, FEV1/FVC, and amount (packs/year) of smoking (p>0.05 for all parameters). FVC% was statistically significantly lower in the appropriate antibiotic prescription group compared with that in the inappropriate antibiotic prescription group (p=0.049).ConclusionThis study shows that most pulmonary physicians have a tendency to prescribe antibiotics for AECOPD according to the defined GOLD criteria. However, some of the physicians also prefer to prescribe antibiotics self-directedly, irrespective of the GOLD criteria. A physician-based questionnaire can be completed for future studies to define the underlying reasons for antibiotic prescription demands for cases of mild AECOPD.

Dataset Information

Npr2 inhibits TORC1 to prevent inappropriate utilization of glutamine for biosynthesis of nitrogen-containing metabolites.

Publications

Npr2 inhibits TORC1 to prevent inappropriate utilization of glutamine for biosynthesis of nitrogen-containing metabolites.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets