Microbial diversity in deep-sea methane seep sediments presented by SSU rRNA gene tag sequencing

http://www.godac.jamstec.go.jp/darwin/cruise/yokosuka/yk06-03/

Isolation and characterization of a thermophilic, obligately anaerobic and heterotrophic marine Chloroflexi bacterium from a Chloroflexi dominated microbial community associated with a Japanese shallow hydrothermal system, and proposal for Thermomarinilinea lacunofontalis gen. nov., sp. nov.

A novel marine thermophilic and heterotrophic Anaerolineae bacterium in the phylum Chloroflexi, strain SW7T, was isolated from an in situ colonization system deployed in the main hydrothermal vent of the Taketomi submarine hot spring field located on the southern part of Yaeyama Archipelago, Japan. The microbial community associated with the hydrothermal vent was predominated by thermophilic heterotrophs such as Thermococcaceae and Anaerolineae, and the next dominant population was thermophilic sulfur oxidizers. Both aerobic and anaerobic hydrogenotrophs including methanogens were detected as minor populations. During the culture-dependent viable count analysis in this study, an Anaerolineae strain SW7T was isolated from an enrichment culture at a high dilution rate. Strain SW7T was an obligately anaerobic heterotroph grew with fermentation, and non-motile thin rods 3.5-16.5 μm in length and 0.2 μm in width constituting multicellular filament. Growth was observed between 37-65 ℃ (optimum 60℃), pH 5.5-7.3 (optimum pH 6.0), 0.5-3.5% (w/v) NaCl concentration (optimum 1.0%). Based on physiological and phylogenetic features of a new isolate, we propose a new species representing a novel genus Thermomarinilinea: the type strain of Thermomarinilinea lacunofontalis sp. nov., is SW7T (= JCM15506T = KCTC5908T)

Separated Transcriptomes of Male Gametophyte and Tapetum in Rice: Validity of a Laser Microdissection (LM) Microarray

In flowering plants, the male gametophyte, the pollen, develops in the anther. Complex patterns of gene expression in both the gametophytic and sporophytic tissues of the anther regulate this process. The gene expression profiles of the microspore/pollen and the sporophytic tapetum are of particular interest. In this study, a microarray technique combined with laser microdissection (44K LM-microarray) was developed and used to characterize separately the transcriptomes of the microspore/pollen and tapetum in rice. Expression profiles of 11 known tapetum specific-genes were consistent with previous reports. Based on their spatial and temporal expression patterns, 140 genes which had been previously defined as anther specific were further classified as male gametophyte specific (71 genes, 51%), tapetum-specific (seven genes, 5%) or expressed in both male gametophyte and tapetum (62 genes, 44%). These results indicate that the 44K LM-microarray is a reliable tool to analyze the gene expression profiles of two important cell types in the anther, the microspore/pollen and tapetum

健常者と味覚異常者における味覚受容体発現

RT-PCR法を用いて,葉状乳頭における味覚受容体の発現を検討した。すなわち葉状乳頭部から擦過法により取得した組織を使用し,味覚受容体候補であるTHTRファミリー(THTRs)およびT2Rファミリー(T2Rs)の発現をRT-PCR後,マイクロキャピラリー電気泳動により測定した。40歳以上の健常者ではTHTRs,T2Rsの受容体において,多数を発現していることが認められた。これに対し30歳以下の被験者ではいくつかのTHTRsおよびT2Rsで発現を認めたが,典型的な発現パターンはなかった。さらに薬服用者や高齢の味覚異常者においては,健常者に比べてTHTRs, T2Rsともに発現していない受容体が多かった。これらのことから,まず青年期では味覚受容体が成長段階にあり,20歳の成人になっても味覚の成長は十分ではないことが考えられた。壮年期になると味覚受容体が十分発達し,高齢者になってもその味覚受容体の発現数は減少しないことが示唆された。また薬剤の服用者や味覚異常者も,味覚受容体の欠落の可能性が示唆された。Tongue tissue from foliate papillae of 22 subjects was scraped and used. The expression of THTR family (THTRs) and T2R family (T2Rs) that are the candidate taste receptors were measured by RT-PCR and micro-capillary electrophoresis. The expression of taste receptors in the foliate papillae was measured using this scraping RT-PCR method. Normal persons over 40 years old expressed many THTRs and T2Rs. In contrast, for people under 30 years old there were some THTRs and T2Rs expressions without typical patterns. The taste disordered persons expressed few kinds of THTRs and T2Rs, and there were no or almost no expressions. These results suggested that in young adults of about 20 years old the taste receptors are not yet developed. We suggest that expression of taste receptors don\u27t decrease in a person of advanced years because taste receptors development peaks in late middle age. With further assay and analyzation of expression of THTRs and T2Rs, it maybe possible to clear up factors of disturbance in taste

Clarithromycin overcomes stromal cell-mediated drug resistance against proteasome inhibitors in myeloma cells via autophagy flux blockage leading to high NOXA expression.

We previously reported that macrolide antibiotics, such as clarithromycin (CAM), blocked autophagy flux, and simultaneous proteasome and autophagy inhibition by bortezomib (BTZ) plus CAM resulted in enhanced apoptosis induction in multiple myeloma (MM) cells via increased endoplasmic reticulum (ER) stress loading. However, in actual therapeutic settings, cell adhesion-mediated drug resistance between bone marrow stromal cells (BMSC) and MM cells has been known to be a barrier to treatment. To investigate whether CAM could enhance BTZ-induced cytotoxicity in MM cells under direct cell adhesion with BMSC, we established a co-culture system of EGFP-labeled MM cells with BMSC. The cytotoxic effect of BTZ on MM cells was diminished by its interaction with BMSC; however, the attenuated cytotoxicity was recovered by the co-administration of CAM, which upregulates ER stress loading and NOXA expression. Knockout of NOXA in MM cells canceled the enhanced cell death by CAM, indicating that NOXA is a key molecule for cell death induction by the co-administration of CAM. Since NOXA is degraded by autophagy as well as proteasomes, blocking autophagy with CAM resulted in the sustained upregulation of NOXA in MM cells co-cultured with BMSC in the presence of BTZ. Our data suggest that BMSC-associated BTZ resistance is mediated by the attenuation of ER stress loading. However, the addition of CAM overcomes BMSC-associated resistance via upregulation of NOXA by concomitantly blocking autophagy-mediated NOXA degradation and transcriptional activation of NOXA by ER stress loading