Identification and characterisation of structural maintenance of chromosome 1 (smc1) mutants of Coprinopsis cinerea

A Coprinopsis cinerea homokaryotic fruiting strain was mutagenised, identifying a mutant that exhibited a hyphal growth temperature sensitive defect and hyphal knot development defect at an early fruiting stage, even at the hyphal growth permissive temperature. Microscopic observation suggested that the mutant nuclei exhibited defects in the metaphase to anaphase transition at the restrictive temperature. The gene in which the mutation occurred was cloned, sequenced and determined to be homologous to smc1. Sequence analyses of the mutant revealed deletion of 28 base pairs in the 19th intron of the Cc.smc1 gene, resulting in complete failure of splicing of that intron and in insertion of 14 amino acids in the C-terminal region of the Cc.Smc1 protein. We isolated eight hyphal growth revertants and identified four intragenic suppressors. All were the result of amino acid substitutions in the C-terminal region. Three of the suppressors caused reversion of the arrest in an early fruiting stage. One of the suppressors exhibited cold sensitivity and failed to suppress the fruiting defect, suggesting that flexibility of a lobe in the C-terminal region is important for proper function of Cc.Smc1.     

Syk expression and novel function in a wide variety of tissues.

Syk protein-tyrosine kinase has been implicated in a variety of hematopoietic cell responses, in particular immunoreceptor signaling events that mediate diverse cellular responses including proliferation, differentiation, and phagocytosis. On the other hand, Syk exhibits a more widespread expression pattern in nonhematopoietic cells like fibroblasts, epithelial cells, breast tissue, hepatocytes, neuronal cells, and vascular endothelial cells and has been shown to be functionally important on these cell types. Thus, Syk appears to play a general physiological function in a wide variety of cells. In this article, we briefly review the current literature regarding the expression and novel function of Syk in various cells and tissues.     

Protective effects of intratracheally administered quercetin on lipopolysaccharide-induced acute lung injury

Background

Acute respiratory distress syndrome (ARDS) can result in a life-threatening form of respiratory failure, and established, effective pharmacotherapies are therefore urgently required. Quercetin is one of the most common flavonoids found in fruits and vegetables, and has potent anti-inflammatory and anti-oxidant activities. Quercetin has been demonstrated to exhibit cytoprotective effects through the induction of heme oxygenase (HO)-1. Here, we investigated whether the intratracheal administration of quercetin could suppress lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice as well as the involvement of HO-1 in quercetin’s suppressive effects.

Methods

Mouse model of ALI were established by challenging intratracheally LPS. The wet lung-to-body weight ratio, matrix metalloproteinase (MMP)-9 activities, and pro-inflammatory cytokine productions, including tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 in bronchoalveolar lavage fluid (BALF) were examined in ALI mice with or without quercetin pretreatment. We also examined the effects of quercetin on LPS stimulation in the mouse alveolar macrophage cell line, AMJ2-C11 cells.

Results

Intratracheal administration of quercetin decreased the wet lung-to-body weight ratio. Moreover, quercetin decreased MMP-9 activity and the production of pro-inflammatory cytokines in BALF cells activated by LPS in advance. We determined the expression of quercetin-induced HO-1 in mouse lung, e.g., alveolar macrophages (AMs), alveolar and bronchial epithelial cells. When AMJ2-C11 cells were cultured with quercetin, a marked suppression of LPS-induced pro-inflammatory cytokine production was observed. The cytoprotective effects were attenuated by the addition of the HO-1 inhibitor SnPP. These results indicated that quercetin suppressed LPS-induced lung inflammation, and that an HO-1-dependent pathway mediated these cytoprotective effects.

Conclusions

Our findings indicated that quercetin suppressed LPS-induced lung inflammation, and that an HO-1-dependent pathway mediated these cytoprotective effects. Intratracheal administration of quercetin will lead to new supportive strategies for cytoprotection in these serious lung conditions.     

Effects of white light on beta-catenin signaling pathway in retinal pigment epithelium

This study investigated the effect of visible light exposure on retinal pigment epithelium (RPE). The activation of Wnt/β-catenin pathway was investigated by immunofluorescence and Western blot analysis using human retinal pigment epithelial (ARPE-19) cells, which demonstrated that the exposure of white light induced the activation of the Wnt/β-catenin pathway. Real time RT-PCR demonstrated that the mRNA of α-smooth muscle actin (α-SMA), and vimentin increased 2.5-4-fold and that of zona occludens 1 (ZO-1) decreased approximately 0.8-fold after white light exposure. The up-regulation of vimentin expression and the down-regulation of ZO-1 were evident by Western blot analysis and immunohistochemistry. Moreover, the ability of phagocytosis of ARPE-19 cells decreased 0.6-fold after light exposure. Together, white light exposure was supposed to induce the activation of Wnt/β-catenin pathway, the changes in the expression markers of epithelial and mesenchymal cells in RPE cells, and the concomitant impairment of the ability of phagocytosis.     

Removal and recovery of phosphorous from swine wastewater by demonstration crystallization reactor and struvite accumulation device

A demonstration crystallization reactor and struvite accumulation device for the removal and recovery of phosphorous was constructed and their performance was evaluated using actual swine wastewater for 3.5 years. The wastewater pH was increased by aeration, and the concentrations of total P and soluble PO(4)-P were reduced by a struvite crystallization reaction induced under a high pH condition. A 30% MgCl(2) addition was effective in enhancing the struvite crystallization reaction. The concentrations of suspended solids, total Zn and total Cu, were also decreased by the settling function of the reactor. On removing the efficiencies of these components, no noticeable seasonal fluctuation in performance was observed during the 3.5-year operation. In terms of maximum yield, 171g struvite was obtained from 1m(3) swine wastewater by the demonstration accumulation device for struvite recovery. The recovered struvite needed only air-drying before use since it was approximately 95% pure even without washing.     

Four-wave mixing signals from β-carotene and its n = 15 homologue

The third-order nonlinear optical responses of β-carotene and its homologue having a conjugation-double bond n = 15 have been investigated using sub-20 fs ultra-short optical pulses in order to clarify the dissipation processes of excess energy. Using the four-wave mixing spectroscopy, we observed a clear coherent oscillation with a period of a few tens of femtoseconds. The spectral density of these molecules was estimated that allowed the theoretical linear and nonlinear optical signals to be directly compared with the experimental data. Calculations based on the Brownian oscillator model were performed under the impulsive excitation limit. We show that the memory of the vibronic coherence generated upon the excitation into the S₂ state is lost via the relaxation process including the S₁ state. The vibronic decoherence lifetime of the system was estimated to be 1 ps, which is about 5 times larger than the life time of the S₂ state (∼150 fs) determined in previous studies. The role of coherence and the efficient energy transfer in the light-harvesting antenna complexes are discussed.