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Summary A monoclonal antibody that recognizes a 140 kDa peripheral plasma membrane protein in pericytes of nervous tissues of the rat is described. Microvessels of brain cortex and perineurium of peripheral nerves are shown to react positively to this antibody. The antigen is absent in brain regions that lack a blood-brain barrier, i.e., choroid plexuses and area postrema. Antigen expression starts as early as day 18 of embryonic development. By means of immuno-electron microscopy the 140 kDa antigen was detected as clusters along the entire circumference of cerebral pericytes. The same antigenic determinant is also expressed in apical domains of plasma membranes of a variety of transporting epithelia, such as hepatocytes, enterocytes of the small intestine, and epithelial cells of proximal tubules of the kidney. We postulate the 140 kDa protein as being a constituent of the pericytes involved in regulative functions of the blood-brain barrier. 相似文献
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Carbonell Ellgutter Jennifer A. Ehrich Dorothee Killengreen Siw T. Ims Rolf A. Unnsteinsdttir Ester R. 《Oecologia》2020,192(2):403-414
Oecologia - Identifying resources driving long-term trends in predators is important to understand ecosystem changes and to manage populations in the context of conservation or control. The arctic... 相似文献
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Maja Hühns Katrin Neumann † Tina Hausmann Friederike Klemke Wolfgang Lockau Uwe Kahmann Lilya Kopertekh Dorothee Staiger Elfriede K. Pistorius Jens Reuther Eva Waldvogel Wolfgang Wohlleben Martin Effmert Holger Junghans Katja Neubauer Udo Kragl Kerstin Schmidt Jörg Schmidtke Inge Broer 《Plant biotechnology journal》2009,7(9):883-898
The production of biodegradable polymers that can be used to substitute petrochemical compounds in commercial products in transgenic plants is an important challenge for plant biotechnology. Nevertheless, it is often accompanied by reduced plant fitness. To decrease the phenotypic abnormalities of the sprout and to increase polymer production, we restricted cyanophycin accumulation to the potato tubers by using the cyanophycin synthetase gene ( cph ATe ) from Thermosynechococcus elongatus BP-1, which is under the control of the tuber-specific class 1 promoter (B33). Tuber-specific cytosolic (pB33- cph ATe ) as well as tuber-specific plastidic (pB33-PsbY- cph ATe ) expression resulted in significant polymer accumulation solely in the tubers. In plants transformed with pB33- cph ATe , both cyanophycin synthetase and cyanophycin were detected in the cytoplasm leading to an increase up to 2.3% cyanophycin of dry weight and resulting in small and deformed tubers. In B33-PsbY- cph ATe tubers, cyanophycin synthetase and cyanophycin were exclusively found in amyloplasts leading to a cyanophycin accumulation up to 7.5% of dry weight. These tubers were normal in size, some clones showed reduced tuber yield and sometimes exhibited brown sunken staining starting at tubers navel. During a storage period over of 32 weeks of one selected clone, the cyanophycin content was stable in B33-PsbY- cph ATe tubers but the stress symptoms increased. However, all tubers were able to germinate. Nitrogen fertilization in the greenhouse led not to an increased cyanophycin yield, slightly reduced protein content, decreased starch content, and changes in the amounts of bound and free arginine and aspartate, as compared with control tubers were observed. 相似文献