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341.
Roland G. Heym Dennis Zimmermann Franziska T. Edelmann Lars Israel Zeynep ?kten David R. Kovar Dierk Niessing 《The Journal of cell biology》2013,203(6):971-984
The assembly and composition of ribonucleic acid (RNA)–transporting particles for asymmetric messenger RNA (mRNA) localization is not well understood. During mitosis of budding yeast, the Swi5p-dependent HO expression (SHE) complex transports a set of mRNAs into the daughter cell. We recombinantly reconstituted the core SHE complex and assessed its properties. The cytoplasmic precomplex contains only one motor and is unable to support continuous transport. However, a defined interaction with a second, RNA-bound precomplex after its nuclear export dimerizes the motor and activates processive RNA transport. The run length observed in vitro is compatible with long-distance transport in vivo. Surprisingly, SHE complexes that either contain or lack RNA cargo show similar motility properties, demonstrating that the RNA-binding protein and not its cargo activates motility. We further show that SHE complexes have a defined size but multimerize into variable particles upon binding of RNAs with multiple localization elements. Based on these findings, we provide an estimate of number, size, and composition of such multimeric SHE particles in the cell. 相似文献
342.
Kerstin P. Kainz Liselotte Krenn Zeynep Erdem Hanspeter Kaehlig Martin Zehl Wilfried Bursch Walter Berger Brigitte Marian 《PloS one》2013,8(6)
Metaxya rostrata C. Presl (Metaxyaceae) is a common tree fern in Central and South America that is used for the treatment of intestinal ulcers and tumours in ethnic medicine. Using a bioactivity-guided strategy 2-deprenyl-rheediaxanthone B (XB) has been isolated as one of the active principles in this plant. XB induced loss of cell viability in colorectal cancer cell lines at IC50 concentrations of 11–23 µM. This was caused by both accumulation of cells in the G2- and S-phase as well as by induction of active cell death in a time and concentration-dependent manner. Cells exposed to XB were incapable of undergoing regular mitosis due to down-regulation of FoxM1 and absence of chromosome condensation. The apoptosis-related proteins Bcl2 and Bclxl were up-regulated so that Caspase 3 was not activated and classical apoptosis was not observed. However, XB triggered damage pathways down-stream of ATR and activated Caspase 2 causing cell death by a mechanism similar to mitotic catastrophe. Our observations are the first to show the cytotoxic activity of 2-deprenyl-rheediaxanthone B and indicate that XB is an interesting new lead compound for cancer therapy that merits further development. 相似文献
343.
Sandra Varum Arianna Baggiolini Luis Zurkirchen Zeynep Kalender Atak Claudio Cantù Elisa Marzorati Raphaël Bossart Jasper Wouters Jessica Häusel Eylül Tuncer Daniel Zingg Dominiek Veen Nessy John Marcel Balz Mitchell P. Levesque Konrad Basler Stein Aerts Nicola Zamboni Lukas Sommer 《Cell Stem Cell》2019,24(4):637-653.e9
344.
Hanyin Cheng Avinash V. Dharmadhikari Sylvia Varland Ning Ma Deepti Domingo Robert Kleyner Alan F. Rope Margaret Yoon Asbjørg Stray-Pedersen Jennifer E. Posey Sarah R. Crews Mohammad K. Eldomery Zeynep Coban Akdemir Andrea M. Lewis Vernon R. Sutton Jill A. Rosenfeld Erin Conboy Katherine Agre Gholson J. Lyon 《American journal of human genetics》2018,102(5):985-994
345.
Gören A Topçu G Bilsel G Bilsel M Aydoğmuş Z Pezzuto JM 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(9-10):797-800
The composition of essential oil of the leaves of Lavandula stoechas ssp. stoechas, was analyzed by means of capillary GC-MS. The main components of L. stoechas ssp. stoechas oil were pulegone (40.4%), menthol (18.1%), menthone (12.6%). The essential oil of the plant was evaluated for antibacterial and a panel cytotoxic activities. 相似文献
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347.
AbstractThis study involves the development and implementation of a STEM activity containing 3?D printer technology, which is commonly used in STEM education. Out of school STEM courses were organized with seven middle school students studying in the 7th grade and the activities in the course were carried out with a 3D printer. One of the activities in the course is the Balance model. The study reveals the skills students used in the Balance Model activity, which is a 3D STEM activity. The students’ engineering skills were effective through the STEM activity, and they actively used skills such as planning, designing, explaining the design process, creating a realistic product, and testing and evaluating product performance. In addition, it was concluded that the students use their academic and technical skills effectively. The study presents in detail the preparation and implementation process of this activity, which we think may help educators uncover and improve students’ engineering skills. 相似文献