PubMed · 10476387
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
1999. Acetamide.. https://pubmed.ncbi.nlm.nih.gov/10476387/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Terminal differentiation of erythroid cells results in terminal cell divisions followed by irreversible cell cycle withdrawal of hemoglobinized cells. The mechanisms leading to cell cycle withdrawal were assessed in stable transfectants of murine erythroleukemia cells, in which the activities of cyclin-dependent kinases (CDKs) and CDK inhibitors (CDKIs) could be tightly regulated during differentiation. Cell cycle withdrawal of differentiating cells is mediated by induction of several CDKIs, thereby leading to inhibition of CDK2 and CDK4. Manipulation of CDK activity in differentiating cells demonstrates that the onset of cell cycle withdrawal can be either greatly accelerated or greatly delayed without affecting hemoglobin levels. Extending the proliferation of differentiating cells requires the synergistic action of CDK2 and CDK4. Importantly, CDK6 cannot substitute for CDK4 in this role, which demonstrates that the 2 cyclin D-dependent kinases are functionally different. The results show that differentiating hemoglobinized cells can be made to proliferate far beyond their normal capacity to divide. (Blood. 2000;96:2755-2764)
Zolpidem is an imidazopyridine with high affinity at gamma-aminobutyric acid(A) (GABA(A)) receptors expressing alpha1 subunits. In squirrel monkeys trained to discriminate a high dose of zolpidem (> or =3.0 mg/kg) from saline, zolpidem and another GABA(A)/alpha1 receptor-preferring agonist, zaleplon, substituted dose-dependently for zolpidem, whereas the non-selective agonists diazepam and triazolam were did not substitute at any dose tested. These findings offer the first evidence for a selective role of GABA(A)/alpha1 receptors in the interoceptive effects of high doses of zolpidem.
Expression of the amidase operon of Pseudomonas aeruginosa is controlled by AmiC, the ligand sensor and negative regulator, and AmiR the transcription antitermination factor activator. We have titrated out AmiC repression activity in vivo by increased AmiR production in trans and shown AmiC regulation of the antitermination activity of AmiR by a steric hindrance mechanism. In the presence of the co-repressor butyramide we have isolated a stable AmiC.AmiR complex. Addition of the inducing ligand acetamide to the complex trips the molecular switch, causing complex dissociation and release of AmiR. The AmiC.AmiR butyramide complex exhibits acetamide-dependent, sequence-specific RNA binding activity and a K(d) of 1.0 nm has been calculated for the AmiR.RNA interaction. The results show that amidase operon expression is controlled by a novel type of signal transduction system in which activity of a site-specific RNA binding activator is regulated via a sequestration mechanism.