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441.
Molecular evolutionary dynamics of cytochrome b in strepsirrhine primates: the phylogenetic significance of third-position transversions 总被引:3,自引:2,他引:1
DNA sequences of the complete cytochrome b gene are shown to contain robust
phylogenetic signal for the strepsirrhine primates (i.e., lemurs and
lorises). The phylogeny derived from these data conforms to other molecular
studies of strepsirrhine relationships despite the fact that uncorrected
nucleotide distances are high for nearly all intrastrepsirrhine
comparisons, with most in the 15%-20% range. Cytochrome b sequences support
the hypothesis that Malagasy lemuriforms and Afro-Asian lorisiforms each
comprise clades that share a sister- group relationship. A study (Adkins
and Honeycutt 1994) of the cytochrome c oxidase subunit II (COII) gene
placed one Malagasy primate (Daubentonia) at the base of the strepsirrhine
clade, thereby suggesting a diphyletic Lemuriformes. The reanalysis of COII
third- position transversions, either alone or in combination with
cytochrome b third-position transversions, however, yields a tree that is
congruent with phylogenetic hypotheses derived from cytochrome b and other
genetic data sets.
相似文献
442.
A binary vector containing two reporter gene cassettes has been developed. This vector is ideal for optimising new plant transformation
systems. Following optimisation, one of the reporter genes can be replaced with a gene of interest; the second can be used
as a marker to confirm transgenic lines, and to estimate locus number and determine zygosity. This allows simple, efficient
and economical screening for homozygous single-insert lines and azygous controls. 相似文献
443.
Wojcik Andrzej Hamza Karim Lundegård Iann Enghag Margareta Haglund Karin Arvanitis Leena Schenk Linda 《Radiation and environmental biophysics》2019,58(1):13-20
Radiation and Environmental Biophysics - The levels of stochastic health effects following exposure to low doses of ionising radiation are not well known. A consequence of the uncertainty is that... 相似文献
444.
Chi F Leider M Leendertz F Bergmann C Boesch C Schenk S Pauli G Ellerbrok H Hakenbeck R 《Journal of bacteriology》2007,189(16):6085-6088
In wild chimpanzees in the Ta? National Park, C?te d'Ivoire, sudden deaths which were preceded by respiratory problems had been observed since 1999. Two new clones of Streptococcus pneumoniae were identified in deceased apes on the basis of multilocus sequence typing analysis and ply, lytA, and pbp2x sequences. The findings suggest that virulent S. pneumoniae occurs in populations of wild chimpanzees with the potential to cause infections similar to those observed in humans. 相似文献
445.
Constanze S?nger Andrea Schenk Lars Ole Schwen Lei Wang Felix Gremse Sara Zafarnia Fabian Kiessling Chichi Xie Weiwei Wei Beate Richter Olaf Dirsch Uta Dahmen 《PloS one》2015,10(11)
Introduction
The intra-hepatic vascular anatomy in rodents, its variations and corresponding supplying and draining territories in respect to the lobar structure of the liver have not been described. We performed a detailed anatomical imaging study in rats and mice to allow for further refinement of experimental surgical approaches.Methods
LEWIS-Rats and C57Bl/6N-Mice were subjected to ex-vivo imaging using μCT. The image data were used for semi-automated segmentation to extract the hepatic vascular tree as prerequisite for 3D visualization. The underlying vascular anatomy was reconstructed, analysed and used for determining hepatic vascular territories.Results
The four major liver lobes have their own lobar portal supply and hepatic drainage territories. In contrast, the paracaval liver is supplied by various small branches from right and caudate portal veins and drains directly into the vena cava. Variations in hepatic vascular anatomy were observed in terms of branching pattern and distance of branches to each other. The portal vein anatomy is more variable than the hepatic vein anatomy. Surgically relevant variations were primarily observed in portal venous supply.Conclusions
For the first time the key variations of intrahepatic vascular anatomy in mice and rats and their surgical implications were described. We showed that lobar borders of the liver do not always match vascular territorial borders. These findings are of importance for the design of new surgical procedures and for understanding eventual complications following hepatic surgery. 相似文献446.
447.
448.
Cyanophora paradoxa ferredoxin is encoded by (cyano-)plastidic DNA, in contrast to those of all other photosynthetic eukaryotes investigated so far. In the present study we report (i) the rapid purification of a chloroplast-type [2Fe-2S] ferredoxin in a two-step procedure by DEAE-Sephadex and Mono Q ion-exchange chromatography; (ii) the biochemical characterization of the purified ferredoxin by electrophoretic separation methods on a microscale; and (iii) a qualitative and quantitative ferredoxin detection method in the femtomole range that allows densitometry, semidry immunoblotting, identification of ferredoxin in soluble cell protein preparations, and analysis of protein biosynthesis from cyanoplast poly(A)- RNA in vivo and in vitro. These fast micromethods should be useful for screening phototrophic species containing ferredoxins encoded by nonnuclear DNA. 相似文献
449.
450.
Agnieszka A Grska Clara Sandmann Eva Riechert Christoph Hofmann Ellen Malovrh Eshita Varma Vivien Kmietczyk Julie
lschlger Lonny Jürgensen Verena KamufSchenk Claudia Stroh Jennifer Furkel Mathias H Konstandin Carsten Sticht Etienne Boileau Christoph Dieterich Norbert Frey Hugo A Katus Shirin Doroudgar Mirko Vlkers 《EMBO reports》2021,22(12)
The mechanistic target of rapamycin (mTOR) promotes pathological remodeling in the heart by activating ribosomal biogenesis and mRNA translation. Inhibition of mTOR in cardiomyocytes is protective; however, a detailed role of mTOR in translational regulation of specific mRNA networks in the diseased heart is unknown. We performed cardiomyocyte genome‐wide sequencing to define mTOR‐dependent gene expression control at the level of mRNA translation. We identify the muscle‐specific protein Cullin‐associated NEDD8‐dissociated protein 2 (Cand2) as a translationally upregulated gene, dependent on the activity of mTOR. Deletion of Cand2 protects the myocardium against pathological remodeling. Mechanistically, we show that Cand2 links mTOR signaling to pathological cell growth by increasing Grk5 protein expression. Our data suggest that cell‐type‐specific targeting of mTOR might have therapeutic value against pathological cardiac remodeling. 相似文献