Screening of drugs that suppress Ste11 MAPKKK activation in yeast identified a c-Abl tyrosine kinase inhibitor

The yeast MAPKKK Ste11 activates three MAP kinase pathways, including pheromone signaling, osmosensing, and pseudohyphal/invasive growth pathways. We identified two chemical compounds, BTB03006 and GK03225, that suppress growth defects induced by Ste11 activation in diploid yeast cells. BTB03006, but not GK03225, was found to suppress growth defects induced by both alpha-factor and Ste4 G(beta) overexpression in the pheromone signaling pathway, suggesting that GK03225 is an osmosensing pathway-specific inhibitor. We also performed genome-wide suppressor analysis for Ste11 activation, using a yeast deletion strains collection, and identified PBS2 and HOG1, and several genes associated with chaperone functions, which represent potential target proteins of the drugs screened from Ste11 activation. GK03225 possesses an Iressa-like quinazoline ring structure, and its chemical analog, 11N-078, suppresses c-Abl human tyrosine kinase activity. These results suggest that drug screening in yeast can identify human tyrosine kinase inhibitors and other drugs for human diseases.     

Nutlet micromorphology of Carex section Rhomboidales sensu Kükenthal (Cyperaceae) and its systematic implications

The sectional delimitation of Carex section Rhomboidales sensu Kükenthal (1909) is problematic and, here, we provide contributions to a systematic understanding of nutlet micromorphology in section Rhomboidales. Nutlet micromorphology of 87 samples representing 71 taxa was investigated using scanning electron microscopy and nine nutlet types were recognized. Although some closely related taxa show similarities, nutlet morphology in section Rhomboidales is stable at the species level and is reliable for species identification. Based on the nutlet characters, section Rhomboidales is delimited and emended as having nutlet rhombic–ovoid, trigonous; beaks conspicuous, erect, rarely curved or coiled; periclinal walls of epidermal cells straight, with zero to two silica bodies. The species with nutlets of the C. harlandii‐type and C. thibetica‐type are included, and species of the C. chinensis‐type and C. macrandrolepsis‐type are ascribed to section Mitratae and section Infossae, respectively. Carex longirostrata and C. pseudolongirostrata (= C. nodaeana), formerly ascribed to section Careyanae or section Depauperatae, are well supported as members of section Rhomboidales. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175 , 123–143.     

Development of a New Method to Track Multiple Honey Bees with Complex Behaviors on a Flat Laboratory Arena

A computer program that tracks animal behavior, thereby revealing various features and mechanisms of social animals, is a powerful tool in ethological research. Because honeybee colonies are populated by thousands of bees, individuals co-exist in high physical densities and are difficult to track unless specifically tagged, which can affect behavior. In addition, honeybees react to light and recordings must be made under special red-light conditions, which the eyes of bees perceive as darkness. The resulting video images are scarcely distinguishable. We have developed a new algorithm, K-Track, for tracking numerous bees in a flat laboratory arena. Our program implements three main processes: (A) The object (bee''s) region is detected by simple threshold processing on gray scale images, (B) Individuals are identified by size, shape and spatiotemporal positional changes, and (C) Centers of mass of identified individuals are connected through all movie frames to yield individual behavioral trajectories. The tracking performance of our software was evaluated on movies of mobile multi-artificial agents and of 16 bees walking around a circular arena. K-Track accurately traced the trajectories of both artificial agents and bees. In the latter case, K-track outperformed Ctrax, well-known software for tracking multiple animals. To investigate interaction events in detail, we manually identified five interaction categories; ‘crossing’, ‘touching’, ‘passing’, ‘overlapping’ and ‘waiting’, and examined the extent to which the models accurately identified these categories from bee''s interactions. All 7 identified failures occurred near a wall at the outer edge of the arena. Finally, K-Track and Ctrax successfully tracked 77 and 60 of 84 recorded interactive events, respectively. K-Track identified multiple bees on a flat surface and tracked their speed changes and encounters with other bees, with good performance.     

Dysbiosis of Salivary Microbiota in Inflammatory Bowel Disease and Its Association With Oral Immunological Biomarkers

Analysis of microbiota in various biological and environmental samples under a variety of conditions has recently become more practical due to remarkable advances in next-generation sequencing. Changes leading to specific biological states including some of the more complex diseases can now be characterized with relative ease. It is known that gut microbiota is involved in the pathogenesis of inflammatory bowel disease (IBD), mainly Crohn''s disease and ulcerative colitis, exhibiting symptoms in the gastrointestinal tract. Recent studies also showed increased frequency of oral manifestations among IBD patients, indicating aberrations in the oral microbiota. Based on these observations, we analyzed the composition of salivary microbiota of 35 IBD patients by 454 pyrosequencing of the bacterial 16S rRNA gene and compared it with that of 24 healthy controls (HCs). The results showed that Bacteroidetes was significantly increased with a concurrent decrease in Proteobacteria in the salivary microbiota of IBD patients. The dominant genera, Streptococcus, Prevotella, Neisseria, Haemophilus, Veillonella, and Gemella, were found to largely contribute to dysbiosis (dysbacteriosis) observed in the salivary microbiota of IBD patients. Analysis of immunological biomarkers in the saliva of IBD patients showed elevated levels of many inflammatory cytokines and immunoglobulin A, and a lower lysozyme level. A strong correlation was shown between lysozyme and IL-1β levels and the relative abundance of Streptococcus, Prevotella, Haemophilus and Veillonella. Our data demonstrate that dysbiosis of salivary microbiota is associated with inflammatory responses in IBD patients, suggesting that it is possibly linked to dysbiosis of their gut microbiota.     

Characterization of sexual reproductive processes in Chara braunii (Charales,Charophyceae)

Chara braunii is distributed worldwide and is the most common charalean species in Japan. This species is monoecious and produces numerous sets of sex organs, each of which consists of one antheridium and one oogonium, under laboratory culture conditions. In this study, we report that light intensity strongly affected the vegetative phase and sexual reproductive phase of this species. Under high‐light conditions (70.0 μmol photons m^?2 s^?1), thalli grew but did not form reproductive organs. Under a low‐light intensity (10.0 μmol photons m^?2 s^?1), algal bodies formed many reproductive organs. In addition, antheridia without the corresponding oogonia (lone antheridia) were observed under low‐light conditions. The absence of oogonium primordia adjacent to the lone antheridium was confirmed by several microscopic approaches. The addition of liquid fertilizer increased the total number of sex organs and growth; however, the number of lone antheridia decreased with increasing fertilizer concentrations. Exogenously applied gibberellin did not affect the number of lone antheridia. These results suggest that regulatory mechanisms for the appropriate allocation of resources exist in this alga, similar to those reported in some land plants.     

In?Vitro Reconstitution of a CaMKII Memory Switch by an NMDA Receptor-Derived Peptide

Ca²⁺/Calmodulin-dependent protein kinase II (CaMKII) has been shown to play a major role in establishing memories through complex molecular interactions including phosphorylation of multiple synaptic targets. However, it is still controversial whether CaMKII itself serves as a molecular memory because of a lack of direct evidence. Here, we show that a single holoenzyme of CaMKII per se serves as an erasable molecular memory switch. We reconstituted Ca²⁺/Calmodulin-dependent CaMKII autophosphorylation in the presence of protein phosphatase 1 in vitro, and found that CaMKII phosphorylation shows a switch-like response with history dependence (hysteresis) only in the presence of an N-methyl-D-aspartate receptor-derived peptide. This hysteresis is Ca²⁺ and protein phosphatase 1 concentration-dependent, indicating that the CaMKII memory switch is not simply caused by an N-methyl-D-aspartate receptor-derived peptide lock of CaMKII in an active conformation. Mutation of a phosphorylation site of the peptide shifted the Ca²⁺ range of hysteresis. These functions may be crucial for induction and maintenance of long-term synaptic plasticity at hippocampal synapses.     

Geographical variation in echolocation call and body size of the Okinawan least horseshoe bat, Rhinolophus pumilus (Mammalia: Rhinolophidae), on Okinawa-jima Island, Ryukyu Archipelago, Japan

The Okinawan least horseshoe bat, Rhinolophus pumilus, is a cave-dwelling species endemic to the central and southern Ryukyus, Japan. We analyzed variation in the constant frequency (CF) of the echolocation call and in forearm length (FAL) of this species on Okinawa-jima Island on the basis of data for 479 individuals from 11 caves scattered over the island. CF values in samples from six caves, all located in the southwestern half of Okinawa-jima, were significantly higher than those in samples from five caves in the northeastern half of the island. Also, FAL was significantly greater in the latter group than in the former group, although the ranges of variation in this character substantially overlapped between the two groups. These results suggest substantial differentiation between R. pumilus populations on Okinawa-jima. The implications of our findings for the conservation of this endangered bat species are briefly discussed.