several important questions. What roles do UNC5 ecto-McMahon (1990) has been well substantiated. Although the exact agrin-induced signaling pathway has yet to be domains play in Netrin responses, and do all Netrins within a species interact similarly with DCC and UNC5? delineated, a key effector protein is rapsyn, a peripheral membrane protein of muscle. Rapsyn can induce clus-Regulation of Net...

Narcolepsy is a usually sporadic disorder with a prevalence of 1:2,000—its importance is not just medical, for it has a major psychosocial impact. Narcolepsy, as described by Gélineau in 1880, presents with excessive daytime sleepiness (EDS) and cataplexy.1 These features and typical findings on multiple sleep latency tests (mean sleep latency 5 to 8 minutes or 2 sleep onset REM periods in 70 t...

RNA was isolated from cultures of Escherichia coli strain MG1655 and derivatives defective in fnr, narXL, or narXL with narP, during aerobic growth, or anaerobic growth in the presence or absence of nitrate or nitrite, in non-repressing media in which both strain MG1655 and an fnr deletion mutant grew at similar rates. Glycerol was used as the non-repressing carbon source and both trimethylamin...

We have previously illustrated the nitrate/nitrite respiratory pathway of Shewanella oneidensis, which is renowned for its remarkable versatility in respiration. Here we investigated the systems regulating the pathway with a reliable approach which enables characterization of mutants impaired in nitrate/nitrite respiration by guaranteeing biomass. The S. oneidensis genome encodes an Escherichia...

The mitochondria are the power plants of the cell; when they are unable to meet the brain’s substantial energy demands, neurodegeneration occurs. Leigh syndrome (LS) and Neuropathy, Ataxia, and Retinitis Pigmentosa (NARP) are two such neurodegenerative diseases, and are caused by dysfunctional ATP synthase. This enzyme is composed of fifteen subunits that work together to couple the flow of pro...

The Escherichia coli K-12 nrf operon promoter can be activated fully by the FNR protein (regulator of fumarate and nitrate reduction) binding to a site centered at position -41.5. FNR-dependent transcription is suppressed by integration host factor (IHF) binding at position -54, and this suppression is counteracted by binding of the NarL or NarP response regulator at position -74.5. The E. coli...

Recent developments to the Local-scale Urban Meteorological Parameterization Scheme (LUMPS), a simple model able to simulate the urban energy balance, are presented. The major development is the coupling of LUMPS to the Net All-Wave Radiation Parameterization (NARP). Other enhancements include that the model now accounts for the changing availability of water at the surface, seasonal variations...

NarL and NarP are paralogous response regulators that control anaerobic gene expression in response to the favoured electron acceptors nitrate and nitrite. Their DNA-binding carboxyl termini are in the widespread GerE-LuxR-FixJ subfamily of tetrahelical helix-turn-helix domains. Previous biochemical and crystallographic studies with NarL suggest that dimerization and DNA binding by the carboxyl...

Escherichia coli possesses three distinct formate dehydrogenase enzymes encoded by the fdnGHI, fdhF, and fdoGHI operons. To examine how two of the formate dehyrogenase operons (fdnGHI and fdhF) are expressed anaerobically in the presence of low, intermediate, and high levels of nitrate, nitrite, and formate, chemostat culture techniques were employed with fdnG-lacZ and fdhF-lacZ reporter fusion...

The NarX and NarQ sensor-histidine kinases control phosphorylation of the NarL and NarP response regulators in response to the respiratory oxidants nitrate and nitrite. Target operon transcription is activated by the Fnr protein in response to anaerobiosis, and it is further activated and/or repressed by the phospho-NarL and phospho-NarP proteins, which bind to heptamer DNA sequences. The locat...