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991.
Sarah Abdul-Wajid Michael T. Veeman Shota Chiba Thomas L. Turner William C. Smith 《Genetics》2014,197(1):49-59
Studies in tunicates such as Ciona have revealed new insights into the evolutionary origins of chordate development. Ciona populations are characterized by high levels of natural genetic variation, between 1 and 5%. This variation has provided abundant material for forward genetic studies. In the current study, we make use of deep sequencing and homozygosity mapping to map spontaneous mutations in outbred populations. With this method we have mapped two spontaneous developmental mutants. In Ciona intestinalis we mapped a short-tail mutation with strong phenotypic similarity to a previously identified mutant in the related species Ciona savignyi. Our bioinformatic approach mapped the mutation to a narrow interval containing a single mutated gene, α-laminin3,4,5, which is the gene previously implicated in C. savignyi. In addition, we mapped a novel genetic mutation disrupting neural tube closure in C. savignyi to a T-type Ca2+ channel gene. The high efficiency and unprecedented mapping resolution of our study is a powerful advantage for developmental genetics in Ciona, and may find application in other outbred species. 相似文献
992.
993.
Jane Mello Lopes Cheila de Lima Boijink Luiz Henrique Florindo Cleo Alcantara Costa Leite Ana Lúcia Kalinin William K. Milsom Francisco Tadeu Rantin 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2010,180(6):797-811
In one series of experiments, heart frequency (f
H), blood pressure (P
a), gill ventilation frequency (f
R
), ventilation amplitude (V
AMP) and total gill ventilation (V
TOT) were measured in intact jeju (Hoplerythrinus unitaeniatus) and jeju with progressive denervation of the branchial branches of cranial nerves IX (glossopharyngeal) and X (vagus) without
access to air. When these fish were submitted to graded hypoxia (water PO2 ~140, normoxia to 17 mmHg, severe hypoxia), they increased f
R
, V
AMP, V
TOT and P
a and decreased f
H. In a second series of experiments, air-breathing frequency (f
RA), measured in fish with access to the surface, increased with graded hypoxia. In both series, bilateral denervation of all
gill arches eliminated the responses to graded hypoxia. Based on the effects of internal (caudal vein, 150 μg NaCN in 0.2 mL
saline) and external (buccal) injections of NaCN (500 μg NaCN in 1.0 mL water) on f
R
, V
AMP, V
TOT, P
a and f
H we conclude that the O2 receptors involved in eliciting changes in gill ventilation and associated cardiovascular responses are present on all gill
arches and monitor the O2 levels of both inspired water and blood perfusing the gills. We also conclude that air breathing arises solely from stimulation
of branchial chemoreceptors and support the hypothesis that internal hypoxaemia is the primary drive to air breathing. 相似文献
994.
Chris D. Evans David M. Cooper Donald T. Monteith Rachel C. Helliwell Filip Moldan Jane Hall Edwin C. Rowe Bernard J. Cosby 《Biogeochemistry》2010,101(1-3):211-227
Data from long-term monitoring sites are vital for biogeochemical process understanding, and for model development. Implicitly or explicitly, information provided by both monitoring and modelling must be extrapolated in order to have wider scientific and policy utility. In many cases, large-scale modelling utilises little of the data available from long-term monitoring, instead relying on simplified models and limited, often highly uncertain, data for parameterisation. Here, we propose a new approach whereby outputs from model applications to long-term monitoring sites are upscaled to the wider landscape using a simple statistical method. For the 22 lakes and streams of the UK Acid Waters Monitoring Network (AWMN), standardised concentrations (Z scores) for Acid Neutralising Capacity (ANC), dissolved organic carbon, nitrate and sulphate show high temporal coherence among sites. This coherence permits annual mean solute concentrations at a new site to be predicted by back-transforming Z scores derived from observations or model applications at other sites. The approach requires limited observational data for the new site, such as annual mean estimates from two synoptic surveys. Several illustrative applications of the method suggest that it is effective at predicting long-term ANC change in upland surface waters, and may have wider application. Because it is possible to parameterise and constrain more sophisticated models with data from intensively monitored sites, the extrapolation of model outputs to policy relevant scales using this approach could provide a more robust, and less computationally demanding, alternative to the application of simple generalised models using extrapolated input data. 相似文献
995.
Nina V Chichkova Jane Shaw Raisa A Galiullina Georgina E Drury Alexander I Tuzhikov Sang Hyon Kim Markus Kalkum Teresa B Hong Elena N Gorshkova Lesley Torrance Andrey B Vartapetian Michael Taliansky 《The EMBO journal》2010,29(6):1149-1161
Caspases are cysteine‐dependent proteases and are important components of animal apoptosis. They introduce specific breaks after aspartate residues in a number of cellular proteins mediating programmed cell death (PCD). Plants encode only distant homologues of caspases, the metacaspases that are involved in PCD, but do not possess caspase‐specific proteolytic activity. Nevertheless, plants do display caspase‐like activities indicating that enzymes structurally distinct from classical caspases may operate as caspase‐like proteases. Here, we report the identification and characterisation of a novel PCD‐related subtilisin‐like protease from tobacco and rice named phytaspase (plant aspartate‐specific protease) that possesses caspase specificity distinct from that of other known caspase‐like proteases. We provide evidence that phytaspase is synthesised as a proenzyme, which is autocatalytically processed to generate the mature enzyme. Overexpression and silencing of the phytaspase gene showed that phytaspase is essential for PCD‐related responses to tobacco mosaic virus and abiotic stresses. Phytaspase is constitutively secreted into the apoplast before PCD, but unexpectedly is re‐imported into the cell during PCD providing insights into how phytaspase operates. 相似文献
996.
997.
Courtney R. LaValle Kara M. George Elizabeth R. Sharlow John S. Lazo Peter Wipf Q. Jane Wang 《生物化学与生物物理学报:癌评论》2010
Protein kinase D is a novel family of serine/threonine kinases and diacylglycerol receptors that belongs to the calcium/calmodulin-dependent kinase superfamily. Evidence has established that specific PKD isoforms are dysregulated in several cancer types, and PKD involvement has been documented in a variety of cellular processes important to cancer development, including cell growth, apoptosis, motility, and angiogenesis. In light of this, there has been a recent surge in the development of novel chemical inhibitors of PKD. This review focuses on the potential of PKD as a chemotherapeutic target in cancer treatment and highlights important recent advances in the development of PKD inhibitors. 相似文献
998.
Rowena L. Long Kimberlyn Williams Erin M. Griffiths Gavin R. Flematti David J. Merritt Jason C. Stevens Shane R. Turner Stephen B. Powles Kingsley W. Dixon 《Annals of botany》2010,105(6):1063-1070
Background and Aims
The smoke-derived compound karrikinolide (KAR1) shows significant potential as a trigger for the synchronous germination of seeds in a variety of plant-management contexts, from weed seeds in paddocks, to native seeds when restoring degraded lands. Understanding how KAR1 interacts with seed physiology is a necessary precursor to the development of the compound as an efficient and effective management tool. This study tested the ability of KAR1 to stimulate germination of seeds of the global agronomic weed Brassica tournefortii, at different hydration states, to gain insight into how the timing of KAR1 applications in the field should be managed relative to rain events.Methods
Seeds of B. tournefortii were brought to five different hydration states [equilibrated at 15 % relative humidity (RH), 47 % RH, 96 % RH, fully imbibed, or re-dried to 15 % RH following maximum imbibition] then exposed to 1 nm or 1 µm KAR1 for one of five durations (3 min, 1 h, 24 h, 14 d or no exposure).Key Results
Dry seeds with no history of imbibition were the most sensitive to KAR1; sensitivity was lower in seeds that were fully imbibed or fully imbibed then re-dried. In addition, reduced sensitivity to KAR1 was associated with an increased sensitivity to exogenously applied abscisic acid (ABA).Conclusions
Seed water content and history of imbibition were found to significantly influence whether seeds germinate in response to KAR1. To optimize the germination response of seeds, KAR1 should be applied to dry seeds, when sensitivity to ABA is minimized. 相似文献999.
O. V. Nakonechnaya A. B. Kholina O. G. Koren V. Janeček A. Kohutka R. Gebauer Y. N. Zhuravlev 《Russian Journal of Genetics》2010,46(12):1417-1425
Genetic variation of Siberian dwarf pine Pinus pumila (Pall.) Regel was characterized in three marginal populations in southwestern, southern and eastern parts of the natural
species range (Baikal Area, Primorye, Kamchatka) using isozyme analysis. Analysis involving 16 isozyme loci encoding ten enzyme
systems was conducted. Our results confirm that P. pumila is one of the most polymorphic species in the genus Pinus. Three marginal populations exhibited high genetic variation (P
95 = 68.8%, H
o = 0.247, H
e = 0.291). Populations heterogeneity and significantly high level of divergence in coniferous (F
ST = 0.050, D
N = 0.044) reflect their genetic originality. In summary, it was shown that the level of genetic variation characteristic for
P. pumila in other parts of the not only is reproduced in the populations examined but even is close to maximum there. 相似文献
1000.
Maggy Jennings David B. Morton Emmanuelle Charton Jane Cooper Coenraad Hendriksen Stella Martin Michael C. Pearce Scott Price Keith Redhead Nick Reed Hugh Simmons Stephen Spencer Hilary Willingale 《Biologicals》2010,38(6):684-695
This report aims to facilitate the implementation of the Three Rs (reduction, refinement and replacement) in the testing of vaccines for regulatory and other purposes. The focus is predominantly on identification of reduction and refinement opportunities in batch potency testing but the principles described are widely applicable to other situations that involve experimental infections of animals. The report should also help to interpret the requirements of the European Pharmacopoeia with regard to the use of alternative tests, humane endpoints and other refinements. Two specific worked examples, for batch potency testing of Clostridium chauvoei and canine leptospira, with recommendations for harmonisation of international test requirements for these and other vaccines, are provided as appendices online. 相似文献