267 research outputs found

    Post-polyploidisation morphotype diversification associates with gene copy number variation

    Get PDF
    Genetic models for polyploid crop adaptation provide important information relevant for future breeding prospects. A well-suited model is Brassica napus, a recent allopolyploid closely related to Arabidopsis thaliana. Flowering time is a major adaptation trait determining life cycle synchronization with the environment. Here we unravel natural genetic variation in B. napus flowering time regulators and investigate associations with evolutionary diversification into different life cycle morphotypes. Deep sequencing of 35 flowering regulators was performed in 280 diverse B. napus genotypes. High sequencing depth enabled high-quality calling of single-nucleotide polymorphisms (SNPs), insertion-deletions (InDels) and copy number variants (CNVs). By combining these data with genotyping data from the Brassica 60 K Illumina® Infinium SNP array, we performed a genome-wide marker distribution analysis across the 4 ecogeographical morphotypes. Twelve haplotypes, including Bna.FLC.A10, Bna.VIN3.A02 and the Bna.FT promoter on C02_random, were diagnostic for the diversification of winter and spring types. The subspecies split between oilseed/kale (B. napus ssp. napus) and swedes/rutabagas (B. napus ssp. napobrassica) was defined by 13 haplotypes, including genomic rearrangements encompassing copies of Bna.FLC, Bna.PHYA and Bna.GA3ox1. De novo variation in copies of important flowering-time genes in B. napus arose during allopolyploidisation, enabling sub-functionalisation that allowed different morphotypes to appropriately fine-tune their lifecycle

    Targeted deep sequencing of flowering regulators in Brassica napus reveals extensive copy number variation

    No full text
    Gene copy number variation (CNV) is increasingly implicated in control of complex trait networks, particularly in polyploid plants like rapeseed (Brassica napus L.) with an evolutionary history of genome restructuring. Here we performed sequence capture to assay nucleotide variation and CNV in a panel of central flowering time regulatory genes across a species-wide diversity set of 280 B. napus accessions. The genes were chosen based on prior knowledge from Arabidopsis thaliana and related Brassica species. Target enrichment was performed using the Agilent SureSelect technology, followed by Illumina sequencing. A bait (probe) pool was developed based on results of a preliminary experiment with representatives from different B. napus morphotypes. A very high mean target coverage of ~670x allowed reliable calling of CNV, single nucleotide polymorphisms (SNPs) and insertion-deletion (InDel) polymorphisms. No accession exhibited no CNV, and at least one homolog of every gene we investigated showed CNV in some accessions. Some CNV appear more often in specific morphotypes, indicating a role in diversification

    Effects of Mixture Quality on Controlled Auto-Ignition

    Get PDF

    A Clathrin light chain A reporter mouse for in vivo imaging of endocytosis

    Get PDF
    Clathrin-mediated endocytosis (CME) is one of the best studied cellular uptake pathways and its contributions to nutrient uptake, receptor signaling, and maintenance of the lipid membrane homeostasis have been already elucidated. Today, we still have a lack of understanding how the different components of this pathway cooperate dynamically in vivo. Therefore, we generated a reporter mouse model for CME by fusing eGFP endogenously in frame to clathrin light chain a (Clta) to track endocytosis in living mice. The fusion protein is expressed in all tissues, but in a cell specific manner, and can be visualized using fluorescence microscopy. Recruitment to nanobeads recorded by TIRF microscopy validated the functionality of the Clta-eGFP reporter. With this reporter model we were able to track the dynamics of Alexa594-BSA uptake in kidneys of anesthetized mice using intravital 2-photon microscopy. This reporter mouse model is not only a suitable and powerful tool to track CME in vivo in genetic or disease mouse models it can also help to shed light into the differential roles of the two clathrin light chain isoforms in health and disease

    Hydropneumbox: yesterday, today, tomorrow

    Get PDF
    Викладено історію розвитку гідроприводу, як найважливішого засобу механізації і автоматизації виробничих процесів. Відзначено внесок вітчизняних вчених у становлення теорії гідравлічного і пневматичного привод у як науки. Підкреслено провідну роль України в розробці та виробництві елементів і систем гідропневмоприводів. Показані нові тенденції і принципи функціонування мехатронних гідропневмосистем, які забезпечили широкомасштабне впровадження їх в гнучкі автоматизовані виробництва.The prerequisites and history of the emergence and development of industrial hydraulic drive as the most important means of mechanization and automation of production processes is outlined. The contribution of domestic scientists in the process of establishing the theory of hydraulic and pneumatic actuator as science is noted. The leading role of Ukraine both in the past and in the post-Soviet space in the development and production of elements and systems of hydro-pneumatic actuators is underlined, the main enterprise-developers and manufacturers of this equipment are listed. Much attention is paid to the modern stage of development of this industry as an integral part of mechatronic systems. New trends and principles of the functioning of mechatronic hydropneumatic systems are shown, which ensured their large-scale introduction into flexible automated production. Examples of modern elements of mechatronic hydropneumatic systems and schemes of their use in industrial processes are given

    Transition to Long Range Magnetic Order in the Highly Frustrated Insulating Pyrochlore Antiferromagnet Gd_2Ti_2O_7

    Full text link
    Experimental evidence from measurements of the a.c. and d.c. susceptibility, and heat capacity data show that the pyrochlore structure oxide, Gd_2Ti_2O_7, exhibits short range order that starts developing at 30K, as well as long range magnetic order at T1T\sim 1K. The Curie-Weiss temperature, θCW\theta_{CW} = -9.6K, is largely due to exchange interactions. Deviations from the Curie-Weiss law occur below \sim10K while magnetic heat capacity contributions are found at temperatures above 20K. A sharp maximum in the heat capacity at Tc=0.97T_c=0.97K signals a transition to a long range ordered state, with the magnetic specific accounting for only \sim 50% of the magnetic entropy. The heat capacity above the phase transition can be modeled by assuming that a distribution of random fields acts on the 8S7/2^8S_{7/2} ground state for Gd3+^{3+}. There is no frequency dependence to the a.c. susceptibility in either the short range or long range ordered regimes, hence suggesting the absence of any spin-glassy behavior. Mean field theoretical calculations show that no long range ordered ground state exists for the conditions of nearest-neighbor antiferromagnetic exchange and long range dipolar couplings. At the mean-field level, long range order at various commensurate or incommensurate wave vectors is found only upon inclusion of exchange interactions beyond nearest-neighbor exchange and dipolar coupling. The properties of Gd$_2Ti_2O_7 are compared with other geometrically frustrated antiferromagnets such as the Gd_3Ga_5O_{12} gadolinium gallium garnet, RE_2Ti_2O_7 pyrochlores where RE = Tb, Ho and Tm, and Heisenberg-type pyrochlore such as Y_2Mo_2O_7, Tb_2Mo_2O_7, and spinels such as ZnFe_2O_4Comment: Letter, 6 POSTSCRIPT figures included. (NOTE: Figure 5 is not included --) To appear in Physical Review B. Contact: [email protected]
    corecore