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81.
This study aimed to investigate whether the presence of trichomes as conspicuous physical attributes of the leaf surface affects
the microbial community composition on Arabidopsis thaliana leaves. The A. thaliana ecotype Col-0 and its trichomeless gl1 mutant were grown in growth cabinets under climate-controlled conditions. The gl1 mutant showed a similar wax composition as the Col-0 wild type with slightly reduced amounts of C29, C31 and C33 alkanes by GC/MS and GC/FID analyses. 120 bacterial isolates representing 39 bacterial genera were obtained from A. thaliana Col-0 leaf surfaces. Phylogenetic analysis of nearly full-length 16S rRNA sequences from 29 selected isolates confirmed their
affiliation to the Proteobacteria (Alpha-, Beta-, Gamma-), Actinobacteria, Bacteroidetes and Firmicutes. The bacterial diversity on A. thaliana ecotype Col-0 and its gl1 mutant, devoid of trichomes, were further compared by denaturing gradient gel electrophoresis (DGGE). Banding patterns and
sequencing of representative DGGE bands revealed the presence of phylotypes related to Sphingomonas (Alphaproteobacteria), Methylophilus (Betaproteobacteria) and Dyadobacter (Bacteroidetes) which are common phyllosphere inhabitants. Furthermore, wildtype and trichomeless mutant plants were exposed to outdoor
conditions for 4–5 weeks. The DGGE gels showed only minor differences between the two plant lines, thus suggesting that trichomes
per se do not affect bacterial diversity on Arabidopsis leaves under the experimental conditions tested. 相似文献
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We studied the kinematics of the knee during weight-bearing active extension in 14 patients with medial osteoarthrosis (OA) and in 10 controls using dynamic radiostereometry. Between 50 degrees and 20 degrees of extension the OA knees showed decreased internal tibial rotation corresponding to less posterior displacement of the lateral femoral flexion facet center. The midpoint between the two tips of the tibial intercondylar eminence occupied a more posterior position within the range of motion analyzed. The observed changes were similar to those previously recorded in chronic tear of the anterior cruciate ligament. Patients with medial arthrosis of the knee joint show a specific and abnormal pattern of joint motion. 相似文献
84.
Aleksandr Klepinin Lyudmila Ounpuu Kati Mado Laura Truu Vladimir Chekulayev Marju Puurand Igor Shevchuk Kersti Tepp Anu Planken Tuuli Kaambre 《Journal of bioenergetics and biomembranes》2018,50(5):339-354
Previous studies have shown that class II β-tubulin plays a key role in the regulation of oxidative phosphorylation (OXPHOS) in some highly differentiated cells, but its role in malignant cells has remained unclear. To clarify these aspects, we compared the bioenergetic properties of HL-1 murine sarcoma cells, murine neuroblastoma cells (uN2a) and retinoic acid - differentiated N2a cells (dN2a). We examined the expression and possible co-localization of mitochondrial voltage dependent anion channel (VDAC) with hexokinase-2 (HK-2) and βII-tubulin, the role of depolymerized βII-tubuline and the effect of both proteins in the regulation of mitochondrial outer membrane (MOM) permeability. Our data demonstrate that neuroblastoma and sarcoma cells are prone to aerobic glycolysis, which is partially mediated by the presence of VDAC bound HK-2. Microtubule destabilizing (colchicine) and stabilizing (taxol) agents do not affect the MOM permeability for ADP in N2a and HL-1 cells. The obtained results show that βII-tubulin does not regulate the MOM permeability for adenine nucleotides in these cells. HL-1 and NB cells display comparable rates of ADP-activated respiration. It was also found that differentiation enhances the involvement of OXPHOS in N2a cells due to the rise in their mitochondrial reserve capacity. Our data support the view that the alteration of mitochondrial affinity for ADNs is one of the characteristic features of cancer cells. It can be concluded that the binding sites for tubulin and hexokinase within the large intermembrane protein supercomplex Mitochondrial Interactosome, could be different between muscle and cancer cells. 相似文献
85.
Single-photon timing with picosecond resolution is used to investigate the effect of Mg2+ on the room-temperature fluorescence decay kinetics in broken spinach chloroplasts. In agreement with an earlier paper (Haehnel, W., Nairn, J.A., Reisberg, P. and Sauer, K. (1982) Biochim. Biophys. Acta 680, 161–173), we find three components in the fluorescence decay both in the presence and in the absence of Mg2+. The behavior of these components is examined as a function of Mg2+ concentration at both the F0 and the Fmax fluorescence levels, and as a function of the excitation intensity for thylakoids from spinach chloroplasts isolated in the absence of added Mg2+. Analysis of the results indicates that the subsequent addition of Mg2+ has effects which occur at different levels of added cation. At low levels of Mg2+ (less than 0.75 mM), there appears to be a decrease in communication between Photosystem (PS) II and PS I, which amounts to a decrease in the spillover rate between PS II and PS I. At higher levels of Mg2+ (about 2 mM), there appears to be an increase in communication between PS II units and an increase in the effective absorption cross-section of PS II, probably both of these involving the chlorophyll light-harvesting antenna. 相似文献
86.
Synergies and trade‐offs between renewable energy expansion and biodiversity conservation – a cross‐national multifactor analysis
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Andrea Santangeli Enrico Di Minin Tuuli Toivonen Mark Pogson Astley Hastings Pete Smith Atte Moilanen 《Global Change Biology Bioenergy》2016,8(6):1191-1200
Increased deployment of renewable energy can contribute towards mitigating climate change and improving air quality, wealth and development. However, renewable energy technologies are not free of environmental impacts; thus, it is important to identify opportunities and potential threats from the expansion of renewable energy deployment. Currently, there is no cross‐national comprehensive analysis linking renewable energy potential simultaneously to socio‐economic and political factors and biodiversity priority locations. Here, we quantify the relationship between the fraction of land‐based renewable energy (including solar photovoltaic, wind and bioenergy) potential available outside the top biodiversity areas (i.e. outside the highest ranked 30% priority areas for biodiversity conservation) within each country, with selected socio‐economic and geopolitical factors as well as biodiversity assets. We do so for two scenarios that identify priority areas for biodiversity conservation alternatively in a globally coordinated manner vs. separately for individual countries. We show that very different opportunities and challenges emerge if the priority areas for biodiversity protection are identified globally or designated nationally. In the former scenario, potential for solar, wind and bioenergy outside the top biodiversity areas is highest in developing countries, in sparsely populated countries and in countries of low biodiversity potential but with high air pollution mortality. Conversely, when priority areas for biodiversity protection are designated nationally, renewable energy potential outside the top biodiversity areas is highest in countries with good governance but also in countries with high biodiversity potential and population density. Overall, these results identify both clear opportunities but also risks that should be considered carefully when making decisions about renewable energy policies. 相似文献
87.
Mika Lännenpää Sinikka Parkkinen Pia Järvinen Juha Lemmetyinen Saila Vepsäläinen Tuuli Savola Kaija Keinonen Markku Keinänen Tuomas Sopanen 《Physiologia plantarum》2005,125(2):268-280
B-function genes determine the identity of petals and stamens in the flowers of model plants such as Arabidopsis and Antirrhinum . Here, we show that a putative B-function gene BpMADS2 , a birch homolog for PISTILLATA , is expressed in stamens and carpels of birch inflorescences. We also present a novel birch gene BpMADS8 , a homolog for APETALA3 / DEFICIENS , which is expressed in stamens. Promoter-GUS analysis revealed that BpMADS2 promoter is active in the receptacle of Arabidopsis flower buds while BpMADS8 promoter is highly specific in mature stamens. BpMADS2 promoter:: BARNASE construct prevented floral organ development in Arabidopsis and tobacco. In birch, inflorescences with degenerated stamens and carpels were obtained. BpMADS8::BARNASE resulted in degeneration of stamens in Arabidopsis and birch causing male sterility. In tobacco, only sepals were developed instead of normal flowers. The results show that the BpMADS2::BARNASE construct can be used to specifically disrupt floral organ development in phylogenetically distant plant species. The stamen-specific promoter of BpMADS8 is a promising tool for biotechnological applications in inducing male sterility or targeting gene expression in the late stamen development. 相似文献
88.
Syaron Basnet Ilona Merikanto Tuuli Lahti Satu Männistö Tiina Laatikainen Erkki Vartiainen 《Chronobiology international》2017,34(4):462-470
Chronotype is an emerging predictor of health and longevity, and understanding its influence on chronic diseases is important for constructing conceptual models of long-term pathways to health. We assessed the associations of chronotype with health status in the general Finnish adult population. Our population-based data were derived from the National FINRISK 2012 study and consisted of 4414 participants, aged 25–74?years, living in Finland. As part of their health examination, participants were asked about their circadian preference to the daily activities (morningness–eveningness) and a diagnosis or treatment for a set of common noncommunicable medical conditions and chronic diseases during the past 12?months. We found that there were 1935 (43.8%) morning types (MTs) and 595 (13.5%) evening types (ETs) and that 1884 (42.7%) were intermediates. As compared with the MTs, the ETs had significantly greater odds for depression (OR = 2.44, 95% CI = 1.52–3.90, p < 0.001) and other mental disorders (OR = 5.18, 95% CI = 2.32–11.52, p < 0.001). The odds were also increased for gallstones, and chronic obstructive pulmonary disease, but these did not remain significant after controlling for multiple testing. Responses to the single-item subjective estimation on the chronotype yielded the association of the definitely evening type of persons with the diagnosis or treatment of cardiac insufficiency (OR = 1.99, 95% CI = 1.02–3.88, p = 0.044) that was corroborated as the greater the eveningness score was, the more common the diagnosis or treatment of cardiac insufficiency was (β = 0.92, 95% CI = 0.85–0.98, p = 0.013). This exploratory study adds further support to the role of evening chronotype in chronic disease risk, albeit underlying mechanisms remain to be elucidated. 相似文献
89.
Zhang QD March G Noel V Piro B Reisberg S Tran LD Hai LV Abadia E Nielsen PE Sola C Pham MC 《Biosensors & bioelectronics》2012,32(1):163-168
We report a signal-on, label-free and reagentless electrochemical DNA biosensor, based on a mixed self-assembled monolayer of thiolated hydroxynaphthoquinone and thiolated oligonucleotide. Electrochemical changes resulting from hybridization were evidenced with oligonucleotide targets (as models), as well as with polymerase chain reaction (PCR) products related to different lineages of Mycobacterium tuberculosis strains. With pure oligonucleotides, this system achieves high sensitivity (~300 pM of DNA target, i.e. 30 fmol in a 100 μL sample) and excellent selectivity, allowing to detect a single mismatch on a sequence of 20 bases. With PCR products, current changes are specific to the bacterial strain from which the PCR fragment is produced. In addition, the sensor response is of the signal-on type, giving a positive signal change upon hybridization, and therefore does not suffer from false positive responses due to non-specific adsorption of DNA. 相似文献
90.
Zharko Daniloski Tristan X. Jordan Hans-Hermann Wessels Daisy A. Hoagland Silva Kasela Mateusz Legut Silas Maniatis Eleni P. Mimitou Lu Lu Evan Geller Oded Danziger Brad R. Rosenberg Hemali Phatnani Peter Smibert Tuuli Lappalainen Benjamin R. tenOever Neville E. Sanjana 《Cell》2021,184(1):92-105.e16
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