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41.
Kamolchanok Umnajkitikorn Nir Sade Maria del Mar Rubio Wilhelmi Matthew E. Gilbert Eduardo Blumwald 《Plant, cell & environment》2020,43(4):920-933
High CO2 concentrations stimulate net photosynthesis by increasing CO2 substrate availability for Rubisco, simultaneously suppressing photorespiration. Previously, we reported that silencing the chloroplast vesiculation (cv) gene in rice increased source fitness, through the maintenance of chloroplast stability and the expression of photorespiration-associated genes. Because high atmospheric CO2 conditions diminished photorespiration, we tested whether CV silencing might be a viable strategy to improve the effects of high CO2 on grain yield and N assimilation in rice. Under elevated CO2, OsCV expression was induced, and OsCV was targeted to peroxisomes where it facilitated the removal of OsPEX11-1 from the peroxisome and delivered it to the vacuole for degradation. This process correlated well with the reduction in the number of peroxisomes, the decreased catalase activity and the increased H2O2 content in wild-type plants under elevated CO2. At elevated CO2, CV-silenced rice plants maintained peroxisome proliferation and photorespiration and displayed higher N assimilation than wild-type plants. This was supported by higher activity of enzymes involved in NO3− and NH4+ assimilation and higher total and seed protein contents. Co-immunoprecipitation of OsCV-interacting proteins suggested that, similar to its role in chloroplast protein turnover, OsCV acted as a scaffold, binding peroxisomal proteins. 相似文献
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Donna J. Shaver Kristen M. Hart Ikuko Fujisaki Cynthia Rubio Autumn R. Sartain Jaime Peña Patrick M. Burchfield Daniel Gomez Gamez Jaime Ortiz 《Ecology and evolution》2013,3(7):2002-2012
For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state‐space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998–2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their “final” foraging sites. We identified new foraging “hotspots” where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13‐year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at‐sea foraging habitats for this imperiled species. 相似文献
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Ignacio Pérez-Valero Alicia González-Baeza Miriam Estébanez María L. Montes-Ramírez Carmen Bayón Federico Pulido José I. Bernardino Francisco X. Zamora Susana Monge Francisco Gaya María Lagarde Rafael Rubio Asunción Hernando Francisco Arnalich José R. Arribas 《PloS one》2013,8(7)
Background
In patients who remain virologically suppressed in plasma with triple-drug ART a switch to protease inhibitor monotherapy maintains high rates of suppression; however it is unknown if protease inhibitor monotherapy is associated to a higher rate of neurocognitive impairment.Methods
In this observational, cross-sectional study we included patients with plasma virological suppression (≥1 year) without concomitant major neurocognitive confounders, currently receiving for ≥1 year boosted lopinavir or darunavir as monotherapy or as triple ART. Neurocognitive impairment was defined as per the 2007 consensus of the American Association of Neurology. The association between neurocognitive impairment and protease inhibitor monotherapy, adjusted by significant confounders, was analysed.Results
Of the 191 included patients - triple therapy: 96, 1–2 years of monotherapy: 40 and >2 years of monotherapy: 55 - proportions (95% CI) with neurocognitive impairment were: overall, 27.2% (20.9–33.6); triple therapy, 31.6% (22.1–41.0); short-term monotherapy, 25.0% (11.3–38.7); long-term monotherapy: 21.4% (10.5–32.3); p = 0.38. In all groups, neurocognitive impairment was mildly symptomatic or asymptomatic by self-report. There were not significant differences in Global Deficit Score by group. In the regression model confounding variables for neurocognitive impairment were years on ART, ethnicity, years of education, transmission category and the HOMA index. Adjusted by these variables the Odds Ratio (95% CI) for neurocognitive impairment of patients receiving short-term monotherapy was 0.85 (0.29–2.50) and for long-term monotherapy 0.40 (0.14–1.15).Conclusions
Compared to triple drug antiretroviral therapy, monotherapy with lopinavir/ritonavir or darunavir/ritonavir in patients with adequate plasma suppression was not associated with a higher rate of asymptomatic neurocognitive impairment than triple drug ART. 相似文献45.
Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biological control. However, at the marginal value product of water, the inclusion of the costs of damage to infrastructure, or the adverse effects of water hyacinth on biodiversity, would justify the use of biological control, even at the low transpiration rate. 相似文献
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Different hypotheses on the genetic control of the resistance to the plum pox virus (PPV) have been reported in apricot, but
there was a lack of agreement about the number of loci involved. In recent years, apricot genetic maps have been constructed
from progenies derived from ‘Stark Early Orange’ or ‘Goldrich’, two main sources of resistance, three of these including the
mapping of the PPV resistance loci. As the location of the locus was not precisely established, we mapped the PPV resistance
loci using interval mapping (IM), composite interval mapping (CIM), and the Kruskal–Wallis non-parametric test in the F1 progeny derived from a cross between the susceptible cv. ‘Polonais’ and ’Stark Early Orange’. Four genomic regions were identified
as being involved in PPV resistance. One of these mapped to the upper region of linkage group 1 of ‘Stark Early Orange’, and
accounted for 56% of the phenotypic variation. Its location was similar to the one previously identified in ‘Goldrich’ and
Prunus davidiana. In addition, a gene strongly associated to these major quantitative trait loci (QTL) was found to be related to PPV infection.
Two putative QTLs were detected on linkage groups 3 of ‘Polonais’ and 5 of both ‘Polonais’ and ‘Stark Early Orange’ with both
parametric and non-parametric methods at logarithm of odds (LOD) scores slightly above the detection threshold. The last QTL
was only detected in the early stage of the infection. PPV resistance is, thus, controlled by a major dominant factor located
on linkage group 1. The hypothesis of recessive factors with lower effect is discussed. 相似文献