A simple method for isolation of nuclei from <Emphasis Type="Italic">Basidiobolus ranarum</Emphasis> (Zygomycota)

A simple method for isolating the nuclei from Basidiobolus ranarum was established. To improve the yield and purity of nuclei, we investigated maceration methods, buffer composition, and centrifugation conditions to establish an optimal procedure. Basidiobolus ranarum cultured for 5 days was enzymatically macerated and then homogenized and filtrated through stainless steel sieves. The crude cell homogenate was loaded on a layer of buffer containing 50% glycerol and centrifuged at 1500 g. The resultant pellet contained pure nuclei.     

Preliminary estimation of chum salmon stock composition in the Bering Sea and North Pacific Ocean using polymorphic microsatellite DNA markers

Variation at the three microsatellite (ms) DNA loci in chum salmon was applied to estimate preliminarily the stock composition using a conditional maximum likelihood method in more than 700 fish collected from 14 stations in the Bering Sea and adjacent North Pacific Ocean during September 2003. Regional stock assignment accuracy with these msDNA markers was nearly the same as the previous estimation with mitochondrial (mt) DNA for the Japanese and North American stocks, but decreased for Russian stocks. The temporal stock estimation with msDNA gave a nonrandom distribution pattern of chum stocks, in that the Japanese and Russian stocks increased in the western to central Bering Sea, and the North American stocks were abundant in the eastern Bering Sea and near the Aleutian Islands. However, predominance of the North American stocks in nearly all of the surveyed area was different from the previous mtDNA estimation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

CERT-mediated trafficking of ceramide

The transport and sorting of lipids from the sites of their synthesis to their appropriate destinations are fundamental for membrane biogenesis. In the synthesis of sphingolipids in mammalian cells, ceramide is newly produced at the endoplasmic reticulum (ER), and transported from the ER to the trans Golgi regions, where it is converted to sphingomyelin. CERT mediates the ER-to-Golgi trafficking of ceramide. CERT contains several functional domains and motifs including i) a START domain capable of catalyzing inter-membrane transfer of ceramide, ii) a pleckstrin homology domain, which serves to target the Golgi apparatus, iii) a FFAT motif which interacts with the ER-resident membrane protein VAP, and iv) a serine-repeat motif, of which hyperphosphorylation down-regulates CERT activity. It has been suggested that CERT extracts ceramide from the ER and carries it to the Golgi apparatus in a non-vesicular manner and that efficient CERT-mediated trafficking of ceramide occurs at membrane contact sites between the ER and the Golgi apparatus.     

Phytoplankton productivity in a pond of brownish-colored water in a Japanese lowland marsh, Naka-ikemi

To understand the characteristics of the ecosystem in Japanese lowland marsh, we investigated chlorophyll-a (Chl. a), photosynthesis and respiration of a phytoplankton community in a brownish-colored pond in Naka-ikemi marsh, Tsuruga, Fukui Prefecture. Chl. a concentrations and volumetric gross primary production rates ranged between 1.3–57.0 μg Chl. a l⁻¹ and 148–1619 μg C l⁻¹ day⁻¹ during the study period. Higher values of Chl. a and primary production rates were clearly observed from June to September, when the dominant algae were the phytoflagellates, Peridinium (Dinophyceae) and Cryptomonas (Cryptophyceae), with swimming ability. The trophic status of the pond water of Naka-ikemi marsh was defined as being in eutrophic condition based on the biomass and productivity of phytoplankton. However, depths of Z _1% showing the productive layer in this study site were relatively narrower than those observed in the hyper-eutrophic Lake Suwa with frequent cyanobacterial water bloom. Factor-attenuating underwater light intensity in Naka-ikemi marsh was presumed to be colored dissolved organic matter. Thus, not only phytoplankton primary production, but also allochthonous organic matter supplied from the catchment area seems to be the dominant factor in the whole energy budget of the pond. In conclusion, we regarded the pond ecosystem in Naka-ikemi marsh to be in a eutrophic–dystrophic condition.     

How is autonomic nervous system activity in subjects who are sleepy but are unable to sleep in the daytime?

We investigated changes in the activity of the autonomic nervous system (ANS) in the relaxed condition in subjects who felt sleepy, but were unable to sleep. A total of 1021 subjects underwent daytime polysomnography. The sleep latency (SL) and the visual analog scale (VAS) were used to assess “immediate” objective and subjective sleepiness, respectively. The subjects were assigned to an “Alert-Alert” group (VAS ≤ 25 mm, SL ≥ 8 min), a “Sleepy-Alert” group (VAS ≥ 75 mm, SL ≥ 8 min), or a “Sleepy-Sleepy” group (VAS ≥ 75 mm, SL ≤ 4 min). In order to assess the ANS, the spectral analysis and the geometric method were used. The ANS data collected during the relaxed condition (after lights off, post-LO) was compared to that obtained during the control condition (before lights off, pre-LO). From the spectral analysis, a significant decrease of sympathetic function and an increase of parasympathetic function at post-LO in the Sleepy-Sleepy group, a tendency for sympathetic function decrease at post-LO in the Alert-Alert group, and no significant changes to sympathetic and parasympathetic function in the Sleepy-Alert group were observed. The results from the geometric method supported the results of the spectral analysis in the Alert-Alert group and the Sleepy-Sleepy group. The results of this study suggest that the ANS plays a role in individuals who are unable to sleep even though they feel sleepy and are given the opportunity to sleep.

     

Hepatocellular protection by nitric oxide or nitrite in ischemia and reperfusion injury

Ischemia and reperfusion (I/R)-induced liver injury occurs in several pathophysiological disorders including hemorrhagic shock and burn as well as resectional and transplantation surgery. One of the earliest events associated with reperfusion of ischemic liver is endothelial dysfunction characterized by the decreased production of endothelial cell-derived nitric oxide (NO). This rapid post-ischemic decrease in NO bioavailability appears to be due to decreased synthesis of NO, enhanced inactivation of NO by the overproduction of superoxide or both. This review presents the most current evidence supporting the concept that decreased bioavailability of NO concomitant with enhanced production of reactive oxygen species initiates hepatocellular injury and that endogenous NO or exogenous NO produced from nitrite play important roles in limiting post-ischemic tissue injury.     

ADP-ribosylation factor like 7 (ARL7) interacts with α-tubulin and modulates intracellular vesicular transport

ADP-ribosylation factor (ARF) like 7 (ARL7, also named ARL4C) is a member of ARL family and recent studies showed that it is involved in the AI-dependent cholesterol secretion process. Yet its biological function remains largely unknown. Using a MALDI-TOF/MS analysis, we identified α-tubulin interacted with ARL7. The interaction was confirmed by GST pull-down assay and co-immunoprecipitation in renal carcinoma cell 786-O in which we found the endogenous ARL7 is expressed. This is the second ARL member found interacting with tubulin after ARL8. In addition, ARL7Q72L, a GTP-binding form, promoted the transferrin transport from early endosome to recycling endosome significantly. The above data suggested that ARL7 might modulate the intracellular vesicular transport via interaction with microtubules.