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191.
Validation of a 1DL earliness per se (eps) flowering QTL in bread wheat (Triticum aestivum) 总被引:1,自引:0,他引:1
Meluleki Zikhali Michelle Leverington-Waite Lesley Fish James Simmonds Simon Orford Luzie U. Wingen Richard Goram Nick Gosman Alison Bentley Simon Griffiths 《Molecular breeding : new strategies in plant improvement》2014,34(3):1023-1033
Vernalization, photoperiod and the relatively poorly defined earliness per se (eps) genes regulate flowering in plants. We report here the validation of a major eps quantitative trait locus (QTL) located on wheat 1DL using near isogenic lines (NILs). We used four independent pairs of NILs derived from a cross between Spark and Rialto winter wheat varieties, grown in both the field and controlled environments. NILs carrying the Spark allele, defined by QTL flanking markers Xgdm111 and Xbarc62, consistently flowered 3–5 days earlier when fully vernalized relative to those with the Rialto. The effect was independent of photoperiod under field conditions, short days (10-h light), long days (16-h light) and very long days (20-h light). These results validate our original QTL identified using doubled haploid (DH) populations. This QTL represents variation maintained in elite north-western European winter wheat germplasm. The two DH lines used to develop the NILs, SR9 and SR23 enabled us to define the location of the 1DL QTL downstream of marker Xgdm111. SR9 has the Spark 1DL arm while SR23 has a recombinant 1DL arm with the Spark allele from Xgdm111 to the distal end. Our work suggests that marker assisted selection of eps effects is feasible and useful even before the genes are cloned. This means eps genes can be defined and positionally cloned in the same way as the photoperiod and vernalization genes have been. This validation study is a first step towards fine mapping and eventually cloning the gene directly in hexaploid wheat. 相似文献
192.
Nick Bowman Dong Liu Patrick Paczkowski Jon Chen John Rossi Sean Mackay Adrian Bot Jing Zhou 《Proteomics》2020,20(13)
Highly multiplexed single‐cell functional proteomics has emerged as one of the next‐generation toolkits for a deeper understanding of functional heterogeneity in cell. Different from the conventional population‐based bulk and single‐cell RNA‐Seq assays, the microchip‐based proteomics at the single‐cell resolution enables a unique identification of highly polyfunctional cell subsets that co‐secrete many proteins from live single cells and most importantly correlate with patient response to a therapy. The 32‐plex IsoCode chip technology has defined a polyfunctional strength index (PSI) of pre‐infusion anti‐CD19 chimeric antigen receptor (CAR)‐T products, that is significantly associated with patient response to the CAR‐T cell therapy. To complement the clinical relevance of the PSI, a comprehensive visualization toolkit of 3D uniform manifold approximation and projection (UMAP) and t‐distributed stochastic neighbor embedding (t‐SNE) in a proteomic analysis pipeline is developed, providing more advanced analytical algorithms for more intuitive data visualizations. The UMAP and t‐SNE of anti‐CD19 CAR‐T products reveal distinct cytokine profiles between nonresponders and responders and demonstrate a marked upregulation of antitumor‐associated cytokine signatures in CAR‐T cells from responding patients. Using this powerful while user‐friendly analytical tool, the multi‐dimensional single‐cell data can be dissected from complex immune responses and uncover underlying mechanisms, which can promote correlative biomarker discovery, improved bioprocessing, and personalized treatment development. 相似文献
193.
To examine the effect of ontogeny on metabolic depression in the cunner (Tautogolabrus adspersus), and to understand how ontogeny and the ability to metabolically depress influence this species'' upper thermal tolerance: 1) the metabolic rate of 9°C-acclimated cunner of three size classes [0.2–0.5 g, young of the year (YOY); 3–6 g, small; and 80–120 g, large (adult)] was measured during a 2°C per day decrease in temperature; and 2) the metabolic response of the same three size classes of cunner to an acute thermal challenge [2°C h−1 from 10°C until Critical Thermal Maximum, CTMax] was examined, and compared to that of the Atlantic cod (Gadus morhua). The onset-temperature for metabolic depression in cunner increased with body size, i.e. from 5°C in YOY cunner to 7°C in adults. In contrast, the extent of metabolic depression was ∼80% (Q10 = ∼15) for YOY fish, ∼65% (Q10 = ∼8) for small fish and ∼55% (Q10 = ∼5) for adults, and this resulted in the metabolic scaling exponent (b) gradually increasing from 0.84 to 0.92 between 9°C to 1°C. All size classes of cunner had significantly (approximately 60%) lower routine metabolic rates at 10°C than Atlantic cod. However, there was no species'' difference in the temperature-induced maximum metabolic rate, and this resulted in factorial metabolic scope values that were more than two-fold greater for cunner, and CTMax values that were 6–9°C higher (∼21 vs. 28°C). These results: 1) show that ontogeny influences the temperature of initiation and the extent of metabolic depression in cunner, but not O2 consumption when in a hypometabolic state; and 2) suggest that the evolution of cold-induced metabolic depression in this northern wrasse species has not resulted in a trade-off with upper thermal tolerance, but instead, an enhancement of this species'' metabolic plasticity. 相似文献
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195.
Polar transport of auxin has been identified as a central element of pattern formation. The polarity of auxin transport is linked to the cycling of pin-formed proteins, a process that is related to actomyosin-dependent vesicle traffic. To get insight into the role of actin for auxin transport, we used patterned cell division to monitor the polarity of auxin fluxes. We show that cell division in the tobacco (Nicotiana tabacum L. cv Bright-Yellow 2) cell line is partially synchronized and that this synchrony can be perturbed by inhibition of auxin transport by 1-N-naphthylphthalamic acid. To address the role of actin in this synchrony, we induced a bundled configuration of actin by overexpressing mouse talin. The bundling of actin impairs the synchrony of cell division and increases the sensitivity to 1-N-naphthylphthalamic acid. Addition of the polarly transported auxins indole-3-acetic acid and 1-naphthyl acetic acid (but not 2,4-dichlorophenoxyacetic acid) restored both the normal organization of actin and the synchrony of cell division. This study suggests that auxin controls its own transport by changing the state of actin filaments. 相似文献
196.
Ma H Jiang WR Robledo N Leveque V Ali S Lara-Jaime T Masjedizadeh M Smith DB Cammack N Klumpp K Symons J 《The Journal of biological chemistry》2007,282(41):29812-29820
beta-D-2'-Deoxy-2'-fluoro-2'-C-methylcytidine (PSI-6130) is a potent inhibitor of hepatitis C virus (HCV) replication in the subgenomic HCV replicon system, and its corresponding 5'-triphosphate is a potent inhibitor of the HCV RNA polymerase in vitro. In this study the formation of PSI-6130-triphosphate was characterized in primary human hepatocytes. PSI-6130 and its 5'-phosphorylated derivatives were identified, and the intracellular concentrations were determined. In addition, the deaminated derivative of PSI-6130, beta-d-2'-deoxy-2'-fluoro-2'-C-methyluridine (RO2433, PSI-6026) and its corresponding phosphorylated metabolites were identified in human hepatocytes after incubation with PSI-6130. The formation of the 5'-triphosphate (TP) of PSI-6130 (PSI-6130-TP) and RO2433 (RO2433-TP) increased with time and reached steady state levels at 48 h. The formation of both PSI-6130-TP and RO2433-TP demonstrated a linear relationship with the extracellular concentrations of PSI-6130 up to 100 mum, suggesting a high capacity of human hepatocytes to generate the two triphosphates. The mean half-lives of PSI-6130-TP and RO2433-TP were 4.7 and 38 h, respectively. RO2433-TP also inhibited RNA synthesis by the native HCV replicase isolated from HCV replicon cells and the recombinant HCV polymerase NS5B with potencies comparable with those of PSI-6130-TP. Incorporation of RO2433-5'-monophosphate (MP) into nascent RNA by NS5B led to chain termination similar to that of PSI-6130-MP. These results demonstrate that PSI-6130 is metabolized to two pharmacologically active species in primary human hepatocytes. 相似文献
197.
Carbon Mineralization and Labile Organic Carbon Pools in the Sandy Soils of a North Florida Watershed 总被引:1,自引:0,他引:1
Mi-Youn Ahn Andrew R. Zimmerman Nick B. Comerford James O. Sickman Sabine Grunwald 《Ecosystems》2009,12(4):672-685
The large pool of actively cycling carbon (C) held in soils is susceptible to release due to changes in landuse, management,
or climate. Yet, the amount and distribution of potentially mineralizable C present in soils of various types and the method
by which this soil C fraction can best be quantified, are not well established. The distribution of total organic C (TOC),
extractable C pools (hot-water-extractable and acid-hydrolyzable), and in vitro mineralizable C in 138 surface soils across
a north Florida watershed was found to be quite heterogeneous. Thus, these C quality parameters could not statistically distinguish
the eight landuses or four major soil orders represented. Only wetland and upland forest soils, with the largest and smallest
C pool size, respectively, were consistently different from the soils of other landuse types. Variations in potential C mineralization
were best explained by TOC (62%) and hot-water-extractable C (59%), whereas acid-hydrolyzable C (32%) and clay content (35%)
were generally not adequate indicators of C bioavailability. Within certain landuse and soil orders (Alfisol, Wetland and
Rangeland, all with >3% clay content), however, C mineralization and clay content were directly linearly correlated, indicating
a possible stimulatory effect of clay on microbial processing of C. Generally, the sandy nature of these surface soils imparted
a lack of protection against C mineralization and likely resulted in the lack of landuse/soil order differences in the soil
C pools. If a single parameter is to be chosen to quantify the potential for soil C mineralization in southeastern U.S. coastal
plain soils, we recommend TOC as the most efficient soil variable to measure.
Author Contributions Conceived of or designed study: Sabine Grunwald, Nick Comerford, and James Sickman—Performed research: Mi-Youn Ahn—Analyzed
data: Mi-Youn Ahn, Andrew Zimmerman, and Nick Comerford—Contributed new methods or models: Andrew Zimmerman, Nick Comerford,
and James Sickman—Wrote the paper: Mi-Youn Ahn, Andrew Zimmerman, and Nick Comerford. 相似文献
198.
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200.
Asprouli Eleni Kalafati Ioanna Panagiota Sakellari Aikaterini Karavoltsos Sotirios Vlachogiannakos John Revenas Konstantinos Kokkinos Alexander Dassenakis Manos Dedoussis George V. Kalogeropoulos Nick 《Biological trace element research》2019,188(2):326-333
Biological Trace Element Research - Nonalcoholic fatty liver disease (NAFLD) is considered as the hepatic manifestation of metabolic syndrome. Its global prevalence is estimated between 25 and 45%,... 相似文献