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961.
Katharina Merkel Florian Schwarzmueller Andrew D. Hulthen Nancy Schellhorn David Williams Anthony R. Clarke 《Journal of Applied Entomology》2019,143(7):754-765
Around the world, several pest tephritids are extending their ranges from warm tropical or Mediterranean climates into cooler temperate regions. The ability to tolerate climatic diversity is uncommon among insects, and understanding the population phenology drivers of such species across different parts of their range will be critical for their management. Here, we determined the role of temperature versus fruit availability on the population phenology of Queensland fruit fly, Bactrocera tryoni. Using a field site located at the subtropical/temperate interface, with host fruits continuously available, we monitored the development times and abundance of B. tryoni, a species which has invaded temperate Australia from the tropics. From fruit samples held at ambient and controlled conditions, the abundance of emerging flies was highly variable among collection dates, but the variance did not reflect the observed changes in temperature. For most samples, the survival rate of flies in a field site was lower than predicted by a day‐degree population model fitted with mean daily field temperatures. The development time of the immature stage in the field was prolonged, presumably due to cooler ambient conditions, but the fitted day‐degree population model consistently over‐predicted estimated development times. Our results indicate that at the subtropical/temperate interface, the decline in B. tryoni populations during winter is only partly driven by temperature and host availability. We classify B. tryoni as a climate generalist, which likely employs physiological as well as behavioural mechanisms to achieve broad climatic tolerance ranges. 相似文献
962.
Florian Kunz Anita Gamauf Frank E. Zachos Elisabeth Haring 《Journal of Zoological Systematics and Evolutionary Research》2019,57(4):942-958
The Northern Goshawk Accipiter gentilis is a medium‐sized bird of prey inhabiting boreal and temperate forests. It has a Holarctic distribution with 10 recognized subspecies. Traditionally, it has been placed within the Accipiter [gentilis] superspecies, together with Henst's Goshawk A. henstii, the Black Sparrowhawk A. melanoleucus, and Meyer's Goshawk A. meyerianus. While those four taxa are geographically separated from each other, hence referred to as allospecies, their phylogenetic relationships are still unresolved. In the present study, we performed phylogenetic analyses on the Accipiter [gentilis] superspecies, including all recognized subspecies of all four allospecies, using partial sequences of two marker loci of the mitochondrial genome, the control region and the cytochrome b gene. We found a deep split within A. gentilis into two monophyletic groups, a Nearctic clade (three subspecies) and a Palearctic clade (seven subspecies). The Palearctic clade is closely related to A. meyerianus, and together these two were more closely related to the other Old World taxa A. henstii and A. melanoleucus, which in turn were reciprocally monophyletic sister species. As a consequence, A. gentilis as usually conceived (including all Holarctic subspecies) was non‐monophyletic. We found a strong genetic homogeneity within Palearctic A. gentilis despite the fact that it comprises seven subspecies distributed from the Atlantic coast in Western Europe to Eastern Siberia. Relationships between the four clades could not be resolved unambiguously. Our results, if confirmed by more integrative data, would imply a taxonomic revision of Nearctic A. gentilis into a separate allospecies, Accipiter [gentilis] atricapillus. 相似文献
963.
Harro Bouwmeester Robert C. Schuurink Petra M. Bleeker Florian Schiestl 《The Plant journal : for cell and molecular biology》2019,100(5):892-907
Volatiles mediate the interaction of plants with pollinators, herbivores and their natural enemies, other plants and micro‐organisms. With increasing knowledge about these interactions the underlying mechanisms turn out to be increasingly complex. The mechanisms of biosynthesis and perception of volatiles are slowly being uncovered. The increasing scientific knowledge can be used to design and apply volatile‐based agricultural strategies. 相似文献
964.
Izabel de Souza Chaves Elias Feitosa-Araújo Alexandra Florian David B. Medeiros Paula da Fonseca‐Pereira Lennart Charton Elmien Heyneke Jorge A.C. Apfata Marcel V. Pires Tabea Mettler‐Altmann Wagner L. Araújo H. Ekkehard Neuhaus Ferdinando Palmieri Toshihiro Obata Andreas P.M. Weber Nicole Linka Alisdair R. Fernie Adriano Nunes‐Nesi 《The Plant journal : for cell and molecular biology》2019,100(3):487-504
Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme required for all living organisms. In eukaryotic cells, the final step of NAD+ biosynthesis is exclusively cytosolic. Hence, NAD+ must be imported into organelles to support their metabolic functions. Three NAD+ transporters belonging to the mitochondrial carrier family (MCF) have been biochemically characterized in plants. AtNDT1 (At2g47490), focus of the current study, AtNDT2 (At1g25380), targeted to the inner mitochondrial membrane, and AtPXN (At2g39970), located in the peroxisomal membrane. Although AtNDT1 was presumed to reside in the chloroplast membrane, subcellular localization experiments with green fluorescent protein (GFP) fusions revealed that AtNDT1 locates exclusively in the mitochondrial membrane in stably transformed Arabidopsis plants. To understand the biological function of AtNDT1 in Arabidopsis, three transgenic lines containing an antisense construct of AtNDT1 under the control of the 35S promoter alongside a T‐DNA insertional line were evaluated. Plants with reduced AtNDT1 expression displayed lower pollen viability, silique length, and higher rate of seed abortion. Furthermore, these plants also exhibited an increased leaf number and leaf area concomitant with higher photosynthetic rates and higher levels of sucrose and starch. Therefore, lower expression of AtNDT1 was associated with enhanced vegetative growth but severe impairment of the reproductive stage. These results are discussed in the context of the mitochondrial localization of AtNDT1 and its important role in the cellular NAD+ homeostasis for both metabolic and developmental processes in plants. 相似文献
965.
Julie Meffre Mehdi Sicre Mohamadou Diarra Florian Marchessaux Dany Paleressompoulle Frederic Ambroggi 《Current biology : CB》2019,29(19):3298-3306.e4
966.
HIV/gp120 decreases adult neural progenitor cell proliferation via checkpoint kinase-mediated cell-cycle withdrawal and G1 arrest 总被引:1,自引:0,他引:1
Okamoto S Kang YJ Brechtel CW Siviglia E Russo R Clemente A Harrop A McKercher S Kaul M Lipton SA 《Cell Stem Cell》2007,1(2):230-236
Impaired adult neurogenesis has been observed in several neurodegenerative diseases, including human immunodeficiency virus (HIV-1)-associated dementia (HAD). Here we report that the HIV-envelope glycoprotein gp120, which is associated with HAD pathogenesis, inhibits proliferation of adult neural progenitor cells (aNPCs) in vitro and in vivo in the dentate gyrus of the hippocampus of HIV/gp120-transgenic mice. We demonstrate that HIV/gp120 arrests cell-cycle progression of aNPCs at the G1 phase via a cascade consisting of p38 mitogen-activated protein kinase (MAPK) --> MAPK-activated protein kinase 2 (a cell-cycle checkpoint kinase) --> Cdc25B/C. Our findings define a molecular mechanism that compromises adult neurogenesis in this neurodegenerative disorder. 相似文献
967.
Lehmann WD Krüger R Salek M Hung CW Wolschin F Weckwerth W 《Journal of proteome research》2007,6(7):2866-2873
The standard strategy for analysis by tandem mass spectrometry of protein phosphorylation at serine or threonine utilizes the neutral loss of H3PO4 (= 97.977/z) from proteolytic peptide molecular ions as marker fragmentation. Manual control of automatically performed neutral loss-based phosphopeptide identifications is strongly recommended, since these data may contain false-positive results. These are connected to the experimental neutral loss m/z error, to competing peptide fragmentation pathways, to limitations in data interpretation software, and to the general growth of protein sequence databases. The fragmentation-related limitations of the neutral loss approach cover (i) the occurrence of abundant 'close-to-98/z' neutral loss fragmentations, (ii) the erroneous assignment of a neutral loss other than loss of H3PO4 due to charge state mix-up, and (iii) the accidental occurrence of any fragment ion in the m/z windows of interest in combination with a charge-state mix-up. The 'close-to-98/z' losses comprise loss of proline (97.053/z), valine (99.068/z), threonine (101.048/z), or cysteine (103.009/z) preferably from peptides with N-terminal sequences PP, VP, TP, or CP, and loss of 105.025/z from alkylated methionine. Confusion with other neutral losses may occur, when their m/z window coincides with a 98/z window as result of a charge state mix-up. Neutral loss of sulfenic acid from oxidized methionine originating from a doubly charged precursor (63.998/2 = 31.999) may thus mimic the loss of phosphoric acid from a triply charged phosphopeptide (97.977/3 = 32.659). As a consequence of the large complexity of proteomes, peptide sequence ions may occur in one of the mass windows of H3PO4 loss around 97.977/z. Practical examples for false-positive annotations of phosphopeptides are given for the first two groups of error. The majority of these can be readily recognized using the guidelines presented in this study. 相似文献
968.
Brier S Maria G Carginale V Capasso A Wu Y Taylor RM Borotto NB Capasso C Engen JR 《The FEBS journal》2007,274(23):6152-6166
The Antarctic notothenioid Trematomus bernacchii (rock cod) lives at a constant mean temperature of -1.9 degrees C. Gastric digestion under these conditions relies on the proteolytic activity of aspartic proteases such as pepsin. To understand the molecular mechanisms of Antarctic fish pepsins, T. bernacchii pepsins A1 and A2 were cloned, overexpressed in Escherichia coli, purified and characterized with a number of biochemical and biophysical methods. The properties of these two Antarctic isoenzymes were compared to those of porcine pepsin and found to be unique in a number of ways. Fish pepsins were found to be more temperature sensitive, generally less active at lower pH and more sensitive to inhibition by pepstatin than their mesophilic counterparts. The specificity of Antarctic fish pepsins was similar but not identical to that of pig pepsin, probably owing to changes in the sequence of fish enzymes near the active site. Gene duplication of Antarctic rock cod pepsins is the likely mechanism for adaptation to the harsh temperature environment in which these enzymes must function. 相似文献
969.
Background
Identifying large gene regulatory networks is an important task, while the acquisition of data through perturbation experiments (e.g., gene switches, RNAi, heterozygotes) is expensive. It is thus desirable to use an identification method that effectively incorporates available prior knowledge – such as sparse connectivity – and that allows to design experiments such that maximal information is gained from each one. 相似文献970.
Christina Staginnus Wolfgang Gregor M Florian Mette Chee How Teo Eduviges Glenda Borroto-Fernández Margit Laimer da Câmara Machado Marjori Matzke Trude Schwarzacher 《BMC plant biology》2007,7(1):24