Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

Cytological studies on the effect of herbicides on plant cells in vivo. I. Hormonic herbicides.

Abstract: In this report, the effect of 12 non-hormonic herbicides were examined mainly on the hair cells of Tradescantia, the stipular ones of Vicia, the pollen grain mitoses of Tradescantia, the petal cells of Allium by in vivo observations, and the root tip cells of Triticurn by fixed preparations.The effects of the herbicides on the materials tested are summarized in Table 2. Among the chemicals, the effect of PCP, ATA and 3cl-IPC solutions on the mitosis induces suppressions of the spindle development in various degrees. Especially, the effect of 3cl-IPC is striking and shows coichicinelike effect.According to the reaction types, the non-hormonic herbicides except TCA are classified into four types: a) The coagulation of protoplasm occurs by the treatment with DNOSBP, CDAA, Fw-450, Fw-734 and PCP solutions in high concentrations. b) Injurious effects are induced on the metabolic cells by the treatment with DPA, CMU, CAT and ATA solutions. c) Mitotic aberrations take place by the treatment with 3cl-IPC and PCP solutions in lower concentrations and by that with ATA solution in high concentrations. d) Inhibition of mitosis occurs in MH 30 solution.In the data obtained by this experiment, some herbicides indicate significant differences on the effects at the cellular level tested between monocotyledonous plants and dicotyledonous ones.

Differential response of type 2 deiodinase gene expression to photoperiod between photoperiodic Fischer 344 and nonphotoperiodic Wistar rats

Abstract: The molecular basis of seasonal or nonseasonal breeding remains unknown. Although laboratory rats are generally regarded as photoperiod-insensitive species, the testicular weight of the Fischer 344 (F344) strain responds to photoperiod. Recently, it was clarified that photoperiodic regulation of type 2 iodothyronine deiodinase (Dio2) in the mediobasal hypothalamus (MBH) is critical in photoperiodic gonadal regulation. Strain-dependent differences in photoperiod sensitivity may now provide the opportunity to address the regulatory mechanism of seasonality by studying Dio2 expression. Therefore, in the present study, we examined the effect of photoperiod on Dio2 expression in photoperiod-sensitive F344 and photoperiod-insensitive Wistar rats. A statistically significant difference was observed between short and long days in terms of testicular weight and Dio2 expression in the F344 strain, while no difference was observed in the Wistar strain. These results suggest that differential responses of the Dio2 gene to photoperiod may determine the strain-dependent differences in photoperiod sensitivity in laboratory rats.

Relative abundance of Δ5‐sterols in plasma membrane lipids of root‐tip cells correlates with aluminum tolerance of rice

Abstract: We investigated variations in aluminum (Al) tolerance among rice plants, using ancestor cultivars from the family line of the Al-tolerant and widely cultivated Japonica cultivar, Sasanishiki. The cultivar Rikuu-20 was Al sensitive, whereas a closely related cultivar that is a descendant of Rikuu-20, Rikuu-132, was Al tolerant. These two cultivars were compared to determine mechanisms underlying variations in Al tolerance. The sensitive cultivar Rikuu-20 showed increased permeability of the plasma membrane (PM) and greater Al uptake within 1 h of Al treatment. This could not be explained by organic acid release. Lipid composition of the PM differed between these cultivars, and may account for the difference in Al tolerance. The tolerant cultivar Rikuu-132 had a lower ratio of phospholipids to Delta(5)-sterols than the sensitive cultivar Rikuu-20, suggesting that the PM of Rikuu-132 is less negatively charged and less permeabilized than that of Rikuu-20. We used inhibitors of Delta(5)-sterol synthesis to alter the ratio of phospholipids to Delta(5)-sterols in both cultivars. These inhibitors reduced Al tolerance in Rikuu-132 and its Al-tolerant ancestor cultivars Kamenoo and Kyoku. In addition, Rikuu-132 showed a similar level of Al sensitivity when the ratio of phospholipids to Delta(5)-sterols was increased to match that of Rikuu-20 after treatment with uniconazole-P, an inhibitor of obtusifoliol-14alpha-demethylase. These results indicate that PM lipid composition is a factor underlying variations in Al tolerance among rice cultivars.