Publications by authors named "Aiko Hirata"

Unlabelled: In , multiple paralogs of SsgA-like proteins (SALPs) are involved in spore formation from aerial hyphae. However, the functions of SALPs have not yet been elucidated in other actinobacterial genera. Here, we report the primary function of an SsgB ortholog (AmSsgB) in , which develops terminal sporangia on the substrate mycelia via short sporangiophores.

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Drug-induced interstitial lung disease(DILD)is a possible complication of many anticancer drugs. When DILD occurs during breast cancer treatment, choosing the right drug for subsequent treatment is often difficult. In our first case, the patient developed DILD during dose-dense AC(ddAC)therapy; however, the disease resolved with steroid pulse therapy, and the patient underwent surgery without disease progression.

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The rare actinomycete forms terminal sporangia containing a few hundred flagellated spores. In response to water, the sporangia open and release the spores into external environments. The orphan response regulator TcrA functions as a global transcriptional activator during sporangium formation and dehiscence.

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The unicellular green alga Haematococcus pluvialis accumulates large amounts of the red ketocarotenoid astaxanthin to protect against environmental stresses. Haematococcus cells that accumulate astaxanthin in the central part (green-red cyst cells) respond rapidly to intense light by distributing astaxanthin diffusively to the peripheral part of the cell within 10 min after irradiation. This response is reversible: when astaxanthin-diffused cells were placed in the dark, astaxanthin was redistributed to the center of the cell.

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Sirtuin has been associated in prolonging lifespan of different model organisms. It has been shown to have an enzymatic activity of NAD-dependent protein deacetylation targeting acetylated proteins. To determine targets and possible roles of sirtuin (LpSirA) in the Lactobacillus paracasei BL23, deletion (ΔsirA), sirtuin overexpressor (highsirA) and GFP fusion (highsirA-Venus) strains were generated, and microscopic localization and cell length analysis were done.

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The rare actinomycete Actinoplanes missouriensis forms terminal sporangia containing a few hundred flagellated spores, which can swim in aquatic environments after release from sporangium. However, gene regulation for its characteristic morphological development is largely unknown. Here, we report the functional analysis of an orphan response regulator, TcrA, which is encoded next to the chemotaxis-flagellar gene cluster.

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When Microbotryum lychnidis-dioicae infects a male Silene latifolia, M. lychnidis-dioicae smut spores develop in the pollen sac instead of pollen. In contrast, when M.

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Mechanisms of suppression of pistil primordia in male flowers and of stamen primordia in female flowers differ in diclinous plants. In this study, we investigated how cell death and cell cycle arrest are related to flower organ formation in Silene latifolia. Using in situ hybridization and a TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay, we detected both cell cycle arrest and cell death in suppressed stamens of female flowers and suppressed pistils of male flowers in S.

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Phosphorus is an essential element for life on earth and is also important for modern agriculture, which is dependent on inorganic fertilizers from phosphate rock. Polyphosphate is a biological polymer of phosphate residues, which is accumulated in organisms during the biological wastewater treatment process to enhance biological phosphorus removal. Here, we investigated the relationship between polyphosphate accumulation and electron-dense bodies in the green alga Parachlorella kessleri.

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Background: Algae have attracted attention as sustainable producers of lipid-containing biomass for food, animal feed, and for biofuels. Parachlorella kessleri, a unicellular green alga belonging to the class Trebouxiophyceae, achieves very high biomass, lipid, and starch productivity levels. However, further biotechnological exploitation has been hampered by a lack of genomic information.

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The high fermentation rate of Saccharomyces cerevisiae sake yeast strains is attributable to a loss-of-function mutation in the RIM15 gene, which encodes a Greatwall-family protein kinase that is conserved among eukaryotes. In the present study, we performed intracellular metabolic profiling analysis and revealed that deletion of the RIM15 gene in a laboratory strain impaired glucose-anabolic pathways through the synthesis of UDP-glucose (UDPG). Although Rim15p is required for the synthesis of trehalose and glycogen from UDPG upon entry of cells into the quiescent state, we found that Rim15p is also essential for the accumulation of cell wall β-glucans, which are also anabolic products of UDPG.

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The mechanosensitive channels, Mys1 and Msy2, in fission yeast are localized in the endoplasmic reticulum membrane and control cytoplasmic Ca(2+) levels in the hypoosmotic response. We here investigated changes in organellar structures with hypoosmotic shock using transmission electron microscopy. While msy1(-) and msy2(-) single mutant cells developed a number of swollen vacuoles following hypoosmotic shock, similar to wild-type cells, msy1(-) msy2(-) double mutant cells only had two abnormally large vacuoles and cracks between the inner and outer nuclear membranes.

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The spore is a dormant cell that is resistant to various environmental stresses. As compared with the vegetative cell wall, the spore wall has a more extensive structure that confers resistance on spores. In the fission yeast Schizosaccharomyces pombe, the polysaccharides glucan and chitosan are major components of the spore wall; however, the structure of the spore surface remains unknown.

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The microalgae family Chlorella species are known to accumulate starch and lipids. Although nitrogen or phosphorous deficiencies promote starch and lipids formation in many microalgae, these deficiencies also limit their growth and productivity. Therefore, the Chlorellaceae strains were attempted to increase starch and lipids productivity under high-light-intensity conditions (600-μmol photons m(-2)s(-1)).

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In order to investigate the mechanisms of anti-mutagenic action by dietary flavonoids, we investigated if they inhibit mutation of the thymidine kinase (tk) gene in L5178Ytk(±) lymphoma cells. Silibinin, quercetin and genistein suppressed mutation of the tk gene induced in L5178Ytk(±) lymphoma cells by methyl methanesulfonate (MMS) and As(3+). Flavone and flavonol were less effective.

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Haematococcus pluvialis is a freshwater species of green algae and is well known for its accumulation of the strong antioxidant astaxanthin, which is used in aquaculture, various pharmaceuticals, and cosmetics. High levels of astaxanthin are present in cysts, which rapidly accumulate when the environmental conditions become unfavorable for normal cell growth. It is not understood, however, how accumulation of high levels of astaxanthin, which is soluble in oil, becomes possible during encystment.

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Chromatin remodelling enzymes such as the histone deacetylases (HDACs) and histone demethylases such as lysine-specific demethylase 1 (LSD1) have been validated as targets for cancer drug discovery. Although a number of HDAC inhibitors have been marketed or are in human clinical trials, the search for isoform-specific HDAC inhibitors is an ongoing effort. In addition, the discovery and development of compounds targeting histone demethylases are in their early stages.

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The influence of sulfur deficiency on biomass production was analyzed in the four Chlorellaceae species, Chlorella vulgaris, Chlorella sorokiniana, Chlorella lobophora, and Parachlorella kessleri. Culturing under sulfur-deficient conditions promoted transient accumulation of starch followed by a steady increase in lipid storage. Transmission electron microscopy indicated an increase and decrease in starch granules and subsequent enlargement of lipid droplets under sulfur-deficient conditions.

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Sporulation in fission yeast represents a unique mode of cell division in which a new cell is formed within the cytoplasm of a mother cell. This event is accompanied by formation of the forespore membrane (FSM), which becomes the plasma membrane of spores. At prophase II, the spindle pole body (SPB) forms an outer plaque, from which formation of the FSM is initiated.

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To elucidate the biological roles of mono-ubiquitinated annexin A1 in nuclei, we investigated the interaction of purified nuclear mono-ubiquitinated annexin A1 with intact and oxidatively damaged DNA. We synthesized the 80mer 5'-GTCCACTATTAAAGAACGTGGACTCCAACGTCAAAGGGCGAAAAACCGTCTATCAGGGCGATGGCCCACTACGTGAACCA-3' (P0G), and four additional 80mers, each with a selected single G in position 14, 30, 37 or 48 replaced by 8-oxo-guanosine (8-oxo-G) to model DNA damaged at a specific site by oxidation. Nuclear mono-ubiquitinated annexin A1 was able to bind oligonucleotides containing 8-oxo-G at specific positions, and able to anneal damaged oligonucleotide DNA to M13mp18 in the presence of Ca(2+) or heavy metals such as As(3+) and Cr(6+).

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Bacillus subtilis is a representative Gram-positive bacterium. In aerobic conditions, this bacterium can generate an electrochemical potential across the membrane with aerobic respiration. Here, we developed the patch clamp method to analyze the respiratory chain in B.

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Protein phosphorylation is pivotal for meiotic progression, but little is known about its regulatory mechanisms. We show that before meiosis I, the meiosis-specific Schizosaccharomyces pombe protein Spo5 is phosphorylated in vivo on T29, T55, S59 and/or T63. In a mutant strain expressing Spo5 fused to green fluorescent protein with alanine substitutions of these amino acid sites (GFP; Spo5-4A-GFP), the timely degradation of Spo5 at meiosis II was not observed.

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Calmodulin in Schizosaccharomyces pombe is encoded by the cam1(+) gene, which is indispensable for both vegetative growth and sporulation. Here, we report how Cam1 functions in spore formation. We found that Cam1 preferentially localized to the spindle pole body (SPB) during meiosis and sporulation.

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Mono-ubiquitinated annexin A1 was purified from rat liver nuclei. The homodimer form of mono-ubiquitinated annexin A1 was able to unwind dsDNA in a Mg(2+)- and ATP-dependent manner, and to anneal ssDNA in a Ca(2+)-dependent manner. Phospholipids decreased the concentration of Ca(2+) required for maximal annealing activity.

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Yeast prion [PSI(+)] is caused by aggregated structures of the Sup35 protein. Although Sup35 forms typical amyloid fibrils in vitro, there is no direct evidence for the fibrillar structures of Sup35 in vivo. We analyzed [PSI(+)] cells in which Sup35 fused with green fluorescent protein (GFP) formed aggregates visible by fluorescence microscopy using thin-section electron microscopy (EM).

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