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81.
Lawrey JD Diederich P Nelsen MP Sikaroodi M Gillevet PM Brand AM van den Boom P 《Fungal biology》2011,115(2):176-187
Lichenicolous fungi are obligately lichen-associated organisms that have evolved many times throughout the Ascomycota and Basidiomycota. Approximately 20% of lichenicolous ascomycetes are recognized only from asexual (anamorphic) characteristics, so the phylogenetic position of many groups has never been resolved. Here we present the first molecular phylogeny of Lichenoconium, a genus of strictly asexual, obligately lichenicolous species with broad geographic distributions and diverse host ecologies. We obtained nuclear and mitochondrial rDNA sequences from fungal cultures isolated from four species in the genus, including a new species, Lichenoconium aeruginosum sp. nov., collected in France, Luxembourg and Netherlands. Our multilocus phylogeny supports the monophyly of fungi in the genus Lichenoconium, and places the genus in the Dothideomycetes, an ascomycete class made up mainly of saprobes and plant-associated endophytes and pathogens. There are only a few recognized groups of lichen-formers in the Dothideomycetes, but Lichenoconium is not supported as being closely related to any of these, nor to any other recognized order within the Dothideomycetes. Given that Lichenoconium is but one of over 100 genera of anamorphic lichenicolous fungi, most of which have never been studied phylogenetically, we suggest that asexual lichenicolous fungi may represent novel and evolutionarily significant phylogenetic groups in the Kingdom Fungi. 相似文献
82.
Masoumeh Safari Faezeh Ghanati Mehrdad Behmanesh Abazar Hajnorouzi Bahareh Nahidian Ghahremani Mina 《Acta Physiologiae Plantarum》2013,35(9):2847-2855
Induction of antioxidant systems of hazel cells by low-energy ultrasound, the potential role of hydrogen peroxide (H2O2) as a signaling molecule in regulation of activity of stress-related enzymes, and expression of catalase (CAT) and phenylalanine ammonialyase (PAL) genes were investigated. Suspension-cultured Corylus avellana L. cells were agitated by an ultrasonic device at 29 kHz with the power of 4 mW/cm2, for 8–40 min. The activities of CAT, superoxide dismutase (SOD), and ascorbate peroxidase (APX) of treated cells increased by 4, 1.7 and 7 times of the control ones, respectively. Induction of increase in the expression of CAT gene started 24 h after the treatment with ultrasound. Significant increase also was observed in the expression of PAL gene, 6 h after exposure to ultrasound, which resulted in turn to increase of total contents of soluble phenolics, 24 h of the treatment. Exposure to ultrasound up to 20 min had no adverse effects on cell viability although it slightly increased the accumulation of H2O2. However, it is likely that this level of increased H2O2 was not deteriorative for hazel cells, but rather triggered antioxidant system and provided hazel cells a sustainable growth after ultrasound treatment. 相似文献
83.
Parry DA Logan CV Hayward BE Shires M Landolsi H Diggle C Carr I Rittore C Touitou I Philibert L Fisher RA Fallahian M Huntriss JD Picton HM Malik S Taylor GR Johnson CA Bonthron DT Sheridan EG 《American journal of human genetics》2011,89(3):451-458
Familial biparental hydatidiform mole (FBHM) is the only known pure maternal-effect recessive inherited disorder in humans. Affected women, although developmentally normal themselves, suffer repeated pregnancy loss because of the development of the conceptus into a complete hydatidiform mole in which extraembryonic trophoblastic tissue develops but the embryo itself suffers early demise. This developmental phenotype results from a genome-wide failure to correctly specify or maintain a maternal epigenotype at imprinted loci. Most cases of FBHM result from mutations of NLRP7, but genetic heterogeneity has been demonstrated. Here, we report biallelic mutations of C6orf221 in three families with FBHM. The previously described biological properties of their respective gene families suggest that NLRP7 and C6orf221 may interact as components of an oocyte complex that is directly or indirectly required for determination of epigenetic status on the oocyte genome. 相似文献
84.
Hu H Eggers K Chen W Garshasbi M Motazacker MM Wrogemann K Kahrizi K Tzschach A Hosseini M Bahman I Hucho T Mühlenhoff M Gerardy-Schahn R Najmabadi H Ropers HH Kuss AW 《American journal of human genetics》2011,89(3):407-414
The genetic variants leading to impairment of intellectual performance are highly diverse and are still poorly understood. ST3GAL3 encodes the Golgi enzyme β-galactoside-α2,3-sialyltransferase-III that in humans predominantly forms the sialyl Lewis a epitope on proteins. ST3GAL3 resides on chromosome 1 within the MRT4 locus previously identified to associate with nonsyndromic autosomal recessive intellectual disability. We searched for the disease-causing mutations in the MRT4 family and a second independent consanguineous Iranian family by using a combination of chromosome sorting and next-generation sequencing. Two different missense changes in ST3GAL3 cosegregate with the disease but were absent in more than 1000 control chromosomes. In cellular and biochemical test systems, these mutations were shown to cause ER retention of the Golgi enzyme and drastically impair ST3Gal-III functionality. Our data provide conclusive evidence that glycotopes formed by ST3Gal-III are prerequisite for attaining and/or maintaining higher cognitive functions. 相似文献
85.
Latifi R Tahsini L Karamzadeh B Safari N Nam W de Visser SP 《Archives of biochemistry and biophysics》2011,507(1):4-13
Manganese-oxo porphyrins have been well studied as biomimetic models of cytochromes P450 and are known to be able to catalyze substrate hydroxylation reactions. Recent experimental studies [J.Y. Lee, Y.-M. Lee, H. Kotani, W. Nam, S. Fukuzumi, Chem. Commun. (2009) 704] showed that Mn(V)-oxo porphyrins react rapidly with 10-methyl-9,10-dihydroacridine (AcrH(2)) via a proton-coupled-electron-transfer followed by an electron transfer. In this work, we present a computational study on the reactivity patterns of Mn(V)-oxo and Mn(IV)-oxo with respect to AcrH(2). This study shows that although both oxidants are capable of hydroxylating AcrH(2), the Mn(V)-oxo species is the more active oxidant. We have generalized these observations with thermodynamic cycles that explain the reaction mechanisms and electron transfer processes. For the Mn(V)-oxo mechanism the reactions proceed with a fast spin state crossing from the ground state singlet to the triplet spin state prior to a hydrogen atom transfer followed by another electron transfer. The present results are fully consistent with previous studies on iron-oxo porphyrins and manganese-oxo porphyrins and shows that the interplay of low lying singlet and triplet spin state surfaces influences the reaction mechanisms and kinetics. 相似文献
86.
Babasafari Mahdieh Kourosharami Masoumeh Behman Jamie Farhadi Mona Komaki Alireza 《International journal of peptide research and therapeutics》2020,26(3):1485-1491
International Journal of Peptide Research and Therapeutics - Orexin-A well-known as hypocretin-1 is a neuropeptide that is produced in the lateral hypothalamus area (LHA). It promotes widespread... 相似文献
87.
Leila J Hamdan Richard B Coffin Masoumeh Sikaroodi Jens Greinert Tina Treude Patrick M Gillevet 《The ISME journal》2013,7(4):685-696
Prokaryote communities were investigated on the seasonally stratified Alaska Beaufort Shelf (ABS). Water and sediment directly underlying water with origin in the Arctic, Pacific or Atlantic oceans were analyzed by pyrosequencing and length heterogeneity-PCR in conjunction with physicochemical and geographic distance data to determine what features structure ABS microbiomes. Distinct bacterial communities were evident in all water masses. Alphaproteobacteria explained similarity in Arctic surface water and Pacific derived water. Deltaproteobacteria were abundant in Atlantic origin water and drove similarity among samples. Most archaeal sequences in water were related to unclassified marine Euryarchaeota. Sediment communities influenced by Pacific and Atlantic water were distinct from each other and pelagic communities. Firmicutes and Chloroflexi were abundant in sediment, although their distribution varied in Atlantic and Pacific influenced sites. Thermoprotei dominated archaea in Pacific influenced sediments and Methanomicrobia dominated in methane-containing Atlantic influenced sediments. Length heterogeneity-PCR data from this study were analyzed with data from methane-containing sediments in other regions. Pacific influenced ABS sediments clustered with Pacific sites from New Zealand and Chilean coastal margins. Atlantic influenced ABS sediments formed another distinct cluster. Density and salinity were significant structuring features on pelagic communities. Porosity co-varied with benthic community structure across sites and methane did not. This study indicates that the origin of water overlying sediments shapes benthic communities locally and globally and that hydrography exerts greater influence on microbial community structure than the availability of methane. 相似文献
88.
Objective:
Ghrelin, orexin, and galanin are orexigenic factors in rodents and humans which participate in adaptive response to weight loss. On the other hand, weight loss and fasting is accompanied by increased levels of epinephrine (Ep) and cortisol (Cor). In this study, we investigated the effects of Ep and Cor on fasting‐induced ghrelin, orexin, and galanin secretion in rats fed different levels of their energy requirements.Design:
Forty five male Wistar rats (300‐350 g, 15 per group) were fed a diet containing 100, 50, and 25% of their energy requirement for 10 days followed by 2 days of fasting. Animals were then anesthetized for carotid artery cannulation for injections and blood samplings.Methods:
Rats received either 3 µg Ep/kg body weight (BW), 3 µg Cor/kg BW, or a combination of those two (0.1 mg in 1 ml of phosphate‐buffered saline). Blood samples were collected before, 30, 60, and 120 min after injection.Results:
In normal and 50% food restricted groups, fasting ghrelin levels fell after Ep and combination of Ep and Cor injection (P ≤ 0.05), whereas, orexin were decreased by combination of Ep and Cor injection in rats fed 100% of their needs and Ep alone in rats fed 50%. Galanin just fell after combination of Ep and Cor injection in both starved (50%) and normal rats. In contrast, all groups whit 25% fed ad libitum did not response to any injections (P > 0.05).Conclusions:
These results indicate that Ep suppresses starvation‐induced secretion of ghrelin, orexin, and galanin in normal (100%) and starved (50%) rats and their response to Ep might be affected by weight loss. 相似文献89.
Hamdan LJ Gillevet PM Pohlman JW Sikaroodi M Greinert J Coffin RB 《FEMS microbiology ecology》2011,77(3):518-532
Sediments from the Porangahau ridge, located off the northeastern coast of New Zealand, were studied to describe bacterial community structure in conjunction with differing biogeochemical regimes across the ridge. Low diversity was observed in sediments from an eroded basin seaward of the ridge and the community was dominated by uncultured members of the Burkholderiales. Chloroflexi/GNS and Deltaproteobacteria were abundant in sediments from a methane seep located landward of the ridge. Gas-charged and organic-rich sediments further landward had the highest overall diversity. Surface sediments, with the exception of those from the basin, were dominated by Rhodobacterales sequences associated with organic matter deposition. Taxa related to the Desulfosarcina/Desulfococcus and the JS1 candidates were highly abundant at the sulfate-methane transition zone (SMTZ) at three sites. To determine how community structure was influenced by terrestrial, pelagic and in situ substrates, sequence data were statistically analyzed against geochemical data (e.g. sulfate, chloride, nitrogen, phosphorous, methane, bulk inorganic and organic carbon pools) using the Biota-Environmental matching procedure. Landward of the ridge, sulfate was among the most significant structuring factors. Seaward of the ridge, silica and ammonium were important structuring factors. Regardless of the transect location, methane was the principal structuring factor on SMTZ communities. 相似文献
90.
Ghaderi M Allameh A Soleimani M Rastegar H Ahmadi-Ashtiani HR 《Mutation research》2011,719(1-2):14-20
This study compared the sensitivity of differentiated hepatocyte-like cells, their progenitor mesenchymal stem cells (MSCs) and CD34(+) stem cells to DNA damage and toxicity induced by aflatoxin B1 (AFB1). The hepatocyte-like cells and their progenitor cells (isolated from umbilical cord blood (UCB)) were each treated with AFB1 on day 15 of differentiation. Cell toxicity and genotoxicity effects were assessed using MTT and alkaline comet assays. AFB1 treatment resulted in a dose- and time-dependent inhibition of cell growth. The IC(50) values of AFB1 for hepatocytes differentiated from CD34(+) and MSCs were within the same range (44.7-46.8μM). The IC(50) calculated for non-differentiated MSCs and CD34(+) cells was slightly lower (42.0-43.4μM) than that calculated for their differentiated counterparts. However, the extent of DNA damage was different in differentiated and non-differentiated cells. The percentages of DNA (% DNA) in comet tails measured in hepatocytes differentiated from MSCs exposed to AFB1 (0, 2.5, 10 and 20μM) for 24h were ~15, 55, 65 and 70%, respectively. In comparison, hepatocytes from CD34(+) cells were more resistant to AFB1-induced DNA damage. Hepatocyte-MSCs were most sensitive to DNA damage, followed by UCB-CD34(+) cells, then UCB-MSCs and finally hepatocyte-CD34(+) cells. These results clearly showed that stem cells from different sources have different sensitivities to DNA damaging agents. These differences can be assigned to the expression levels of cytochrome P450 (CYP) particularly CYP3A4 in non-differentiated and differentiated cells. These data are useful in better understanding the susceptibility/resistance of stem cells in the process of differentiation to environmental toxicants. 相似文献