Correction to: Comparison of the usability of an automatic sleep staging program via portable 1-channel electroencephalograph and manual sleep staging with traditional polysomnography

Sleep and Biological Rhythms -     

Japanese clinical guideline for sleep apnea syndrome (SAS)

Sleep and Biological Rhythms -     

Resetting of peripheral circadian clock by prostaglandin E2

In mammals, the master circadian pacemaker is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN is thought to drive peripheral oscillators by controlling neuronal and humoral signals that can entrain the peripheral clocks. Here, we show that prostaglandin E2 (PGE2), a proinflammatory compound known to have diverse biological effects, is able to act as an in vivo clock-resetting agent. We find that in cultured NIH3T3 fibroblasts, PGE2 is able to induce transient expression of Period 1 messenger RNA and the following circadian oscillation of clock gene expression. Furthermore, we demonstrate that intraperitoneal administration of PGE2 results in the phase shift of circadian gene expression in mouse peripheral tissues in a time-dependent manner. This phase shift is also induced by the EP1/EP3 agonist sulprostone but not by the EP2 agonist butaprost. The PGE2-induced phase shift is inhibited by the EP1 antagonist SC-51322. These results suggest that PGE2 acts as an in vivo clock-resetting factor by means of the EP1 subtype of PGE receptors.     

Binding of Phylogenetically Distant Bacillus thuringiensis Cry Toxins to a Bombyx mori Aminopeptidase N Suggests Importance of Cry Toxin's Conserved Structure in Receptor Binding

We investigated the binding proteins for three Cry toxins, Cry1Aa, Cry1Ac, and the phylogenetically distant Cry9Da, in the midgut cell membrane of the silkworm. In a ligand blot experiment, Cry1Ac and Cry9Da bound to the same 120-kDa aminopeptidase N (APN) as Cry1Aa. A competition experiment with the ligand blot indicated that the three toxins share the same binding site on several proteins. The values of the dissociation constants of the three Cry toxins and 120-kDa APN are as low as the case of other Cry toxins and receptors. These results suggest that distantly related Cry toxins bind to the same site on the same proteins, especially with APN. We propose that the conserved structure in these three toxins includes the receptor-binding site. Received: 12 January 1998 / Accepted: 17 February 1999     

Bacillus thuringiensis Cry1Aa toxin-binding region of Bombyx mori aminopeptidase N

The Bacillus thuringiensis Cry1Aa toxin-binding region of Bombyx mori aminopeptidase N (APN) was analyzed, to better understand the molecular mechanism of susceptibility to the toxin and the development of resistance in insects. APN was digested with lysylendopeptidase and the ability of the resulting fragments to bind to Cry1Aa and 1Ac toxins was examined. The binding abilities of the two toxins to these fragments were different. The Cry1Aa toxin bound to the fragment containing 40-Asp to 313-Lys, suggesting that the Cry1Aa toxin-binding site is located in the region between 40-Asp and 313-Lys, while Cry1Ac toxin bound exclusively to mature APN. Next, recombinant APN of various lengths was expressed in Escherichia coli cells and its ability to bind to Cry1Aa toxin was examined. The results localized the Cry1Aa toxin binding to the region between 135-Ile and 198-Pro.     

The sleep disorder canine narcolepsy is caused by a mutation in the hypocretin (orexin) receptor 2 gene.

Narcolepsy is a disabling sleep disorder affecting humans and animals. It is characterized by daytime sleepiness, cataplexy, and striking transitions from wakefulness into rapid eye movement (REM) sleep. In this study, we used positional cloning to identify an autosomal recessive mutation responsible for this sleep disorder in a well-established canine model. We have determined that canine narcolepsy is caused by disruption of the hypocretin (orexin) receptor 2 gene (Hcrtr2). This result identifies hypocretins as major sleep-modulating neurotransmitters and opens novel potential therapeutic approaches for narcoleptic patients.     

Bacillus thuringiensis Cry toxins bound specifically to various proteins via domain III, which had a galactose-binding domain-like fold

Cry toxins have been reported to bind not only to receptors on insect cells but also to several unrelated proteins. In this study, we investigated the binding properties of Bacillus thuringiensis Cry toxins, focusing on domain III, a Cry toxin region with a structure that of the galactose-binding domain-like. Cry1Aa, Cry1Ac, and Cry8Ca specifically bound to several proteins unrelated to insect midgut cells. Cry1Aa binding to Cry toxin-binding proteins was inhibited by a monoclonal antibody, 2C2, indicating that Cry1Aa binds to these Cry toxin-binding proteins through domain III. Cry1Aa binding to Bombyx mori aminopeptidase N and other Cry toxin-binding proteins was inhibited by carbonic anhydrase, a Cry toxin-binding protein. The binding regions of carbonic anhydrase and Bombyx mori aminopeptidase N were narrowed to regions of less than 20 amino acids that did not have any similarity, suggesting that Cry toxin domain III has a binding pocket for multiple proteins.     

Evolution and Diversification of RNA Silencing Proteins in Fungi

Comprehensive phylogenetic analyses of fungal Argonaute, Dicer, and RNA-dependent RNA polymerase-like proteins have been performed to gain insights into the diversification of RNA silencing pathways during the evolution of fungi. A wide range of fungi including ascomycetes, basidiomycetyes, and zygomycetes possesses multiple RNA silencing components in the genome, whereas a portion of ascomycete and basidiomycete fungi apparently lacks the whole or most of the components. The number of paralogous silencing proteins in the genome differs considerably among fungal species, suggesting that RNA silencing pathways have diversified significantly during evolution in parallel with developing the complexity of life cycle or in response to environmental conditions. Interestingly, orthologous silencing proteins from different fungal clades are often clustered more closely than paralogous proteins in a fungus, indicating that duplication events occurred before speciation events. Therefore, the origin of multiple RNA silencing pathways seems to be very ancient, likely having occurred prior to the divergence of the major fungal lineages. Electronic Supplementary Material Electronic Supplementary material is available for this article at and accessible for authorised users. [Reviewing Editor: Dr. Rüdiger Cerff]