Review of the East Asian species of the genera Hybrizon Fallén and Ghilaromma Tobias (Hymenoptera: Ichneumonidae: Hybrizontinae)

East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided.     

The AtXTH28 Gene, a Xyloglucan Endotransglucosylase/Hydrolase, is Involved in Automatic Self-Pollination in Arabidopsis thaliana

Successful automatic self-pollination in flowering plants isdependent on the correct development of reproductive organs.In the stamen, the appropriate growth of the filament, whichlargely depends on the mechanical properties of the cell wall,is required to position the anther correctly close to the stigmaat the pollination stage. Xyloglucan endotransglucosylase/hydrolases(XTHs) are a family of enzymes that mediate the constructionand restructuring of xyloglucan cross-links, thereby controllingthe extensibility or mechanical properties of the cell wallin a wide variety of plant tissues. Our reverse genetic analysishas revealed that a loss-of-function mutation of an ArabidopsisXTH family gene, AtXTH28, led to a decrease in capability forself-pollination, probably due to inhibition of stamen filamentgrowth. Our results also suggest that the role of AtXTH28 inthe development of the stamen is not functionally redundantwith its closest paralog, AtXTH27. Thus, our finding indicatesthat AtXTH28 is specifically involved in the growth of stamenfilaments, and is required for successful automatic self-pollinationin certain flowers in Arabidopsis thaliana.     

Electron-microscopic study of innervation of smooth muscle cells surrounding collecting tubules of the fish kidney

Summary The fine structure of the collecting tubules of the trout and killifish kidney was studied. These tubules are surrounded by layers of smooth muscle cells which are commonly innervated. The nerve terminals contain synaptic vesicles and, occasionally, a few dense-cored granules as well. Capillaries occur in the connective tissue space between these smooth muscle cells and the collecting tubule. Epithelial cells of the collecting tubules contain abundant mitochondria and a well developed membrane system displaying parallel arrays, and were considered to be actively involved in the transport of materials. In the trout, the collecting tubules contain peculiar cells in addition to regular tubule cells. The fine structure of these peculiar cells is highly reminiscent of that of gill chloride cells. The significance of these findings may be summarized as follows: If the smooth muscles around the collecting tubule contract under neural influence, intratubular pressure may be increased and, thus affect glomerular filtration rate. The contraction of these muscles may also cause the collapse of peritubular capillaries, affecting the transport activity of tubule cells.     

Kinetochore stretching-mediated rapid silencing of the spindle-assembly checkpoint required for failsafe chromosome segregation

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Sulfonamide-based non-alkyne LpxC inhibitors as Gram-negative antibacterial agents

We attempted to optimize sulfonamide-based non-alkyne LpxC inhibitors by focusing on improvements in enzyme inhibitory and antibacterial activity. It was discovered that inhibitors possessing 2-aryl benzofuran as a hydrophobe exhibited good activity. In particular, compound 21 displayed impressive antibacterial activity (E. coli MIC = 0.063 μg/mL, K. pneumoniae MIC = 0.5 μg/mL, and P. aeruginosa MIC = 0.5 μg/mL), and is a promising lead for further exploration as an antibacterial agent.