0000000000529198
AUTHOR
Gabriele Wagner
Multifactorial and Species-Specific Feedback Regulation of the RNA Surveillance Pathway Nonsense-Mediated Decay in Plants
Abstract Nonsense-mediated decay (NMD) is an RNA surveillance mechanism that detects aberrant transcript features and triggers degradation of erroneous as well as physiological RNAs. Originally considered to be constitutive, NMD is now recognized to be tightly controlled in response to inherent signals and diverse stresses. To gain a better understanding of NMD regulation and its functional implications, we systematically examined feedback control of the central NMD components in two dicot and one monocot species. On the basis of the analysis of transcript features, turnover rates and steady-state levels, up-frameshift (UPF) 1, UPF3 and suppressor of morphological defects on genitalia (SMG)…
Suppression by cholinesterase inhibition of a Ca(2+)-independent efflux of [3H]acetylcholine from the neuromuscular junction of the isolated rat diaphragm.
Abstract Endplate preparations of the left rat hemidiaphragm were incubated with [ 3 H]choline to label neuronal acetylcholine stores. Elevation of the concentration (13.5–135 mmol/l) of extracellular potassium chloride (KC1) stimulated the release of [ 3 H]acetylcholine in a concentration-dependent manner. KC1 (27 mmol/l) still caused a significant efflux of [ 3 H]acetylcholine in a Ca 2+ -free medium. Inhibitors of cholinesterase (physostigmine, diisopropylfluorophosphate) suppressed by 80% this Ca 2+ -independent efflux of [ 3 H]acetylcholine. Vesamicol (10 μmol/l), the blocker of the vesicular acetylcholine carrier, also suppressed the stimulated, Ca 2+ -independent efflux of [ 3 H]acet…