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1.
2.
Andreas Ritter Mourad Sanhaji Alexandra Friemel Susanne Roth Udo Rolle Frank Louwen Juping Yuan 《Cell cycle (Georgetown, Tex.)》2015,14(23):3755-3767
Mitotic centromere-associated kinesin (MCAK) is the best characterized member of the kinesin-13 family and plays important roles in microtubule dynamics during mitosis. Its activity and subcellular localization is tightly regulated by an orchestra of mitotic kinases, such as Aurora B. It is well known that serine 196 of MCAK is the major phosphorylation site of Aurora B in Xenopus leavis extracts and that this phosphorylation regulates its catalytic activity and subcellular localization. In the current study, we have addressed the conserved phosphorylation site serine 192 in human MCAK to characterize its function in more depth in human cancer cells. Our data confirm that S192 is the major phosphorylation site of Aurora B in human MCAK and that this phosphorylation has crucial roles in regulating its catalytic activity and localization at the kinetochore/centromere region in mitosis. Interfering with this phosphorylation leads to a delayed progression through prometa- and metaphase associated with mitotic defects in chromosome alignment and segregation. We show further that MCAK is involved in directional migration and invasion of tumor cells, and interestingly, interference with the S192 phosphorylation affects this capability of MCAK. These data provide the first molecular explanation for clinical observation, where an overexpression of MCAK was associated with lymphatic invasion and lymph node metastasis in gastric and colorectal cancer patients. 相似文献
3.
Paul Karila Ann-Cathrine Jönsson Jörgen Jesen Susanne Holmgren 《Cell and tissue research》1993,271(3):537-544
The presence of galanin-like immunoreactivity in nerves to the stomach of the Atlantic cod has been investigated by immunohistochemistry. The distribution of ganglion cells showing galanin-like immunoreactivity was compared with the total distribution in nerves and ganglia. Projection studies were made to determine the origin of the galanin neurons. The effect of galanin was studied in smooth muscle strip preparations of the gut wall and arteries. Galanin-like immunoreactive ganglion cells frequently occurred along the vagal branches to the stomach. Most of them projected cranially. Immunoreactive nerve fibres were present in all layers of the gut and around arterial branches on the surface of the stomach. Ligations of the vagus and splanchnic nerves produced accumulations of immunoreactive material on both sides of the ligature. Galanin produced weak contractile effects unaffected by tetrodotoxin on the gut wall and on gut arteries. It is concluded that a population of the ganglion cells along the vagus nerve in the Atlantic cod contains a galanin-like peptide. Some of these cells may be parts of autonomic parasympathetic pathways innervating the gut of the Atlantic cod, having direct excitatory effects on the smooth muscles of the gut wall and gut arteries. 相似文献
4.
L Norrheim H S?rensen K Gautvik J Bremer O Spydevold 《Biochimica et biophysica acta》1990,1051(3):319-323
(1) The relation between the effects of the sulfur-substituted fatty acid analogue, tetradecylthioacetic acid (TTA), dexamethasone and insulin on enzyme induction and growth rate was studied in Morris hepatoma 7800 C1 cells in culture. (2) The activities of the cynanide-insensitive palmitoyl-CoA oxidase and palmitoyl-CoA hydrolase were induced about 2-fold by 50 microM TTA after 72 h of treatment. Catalase was less induced and NADPH-cytochrome-c2 reductase, glucose-6-phosphate dehydrogenase and lactate dehydrogenase were unaffected by the fatty acid analogue. (3) Dexamethasone (250 nM) induced the same enzymes as did TTA, but was a less efficient than 50 microM TTA. However, in combination their effects were more than additive, resulting in 4-7-fold increases. (4) Insulin (400 nM) counteracted the inductive effects of both TTA and dexamethasone on all enzymes except for lactate dehydrogenase, which was induced by the combination of all three compounds. (5) TTA inhibited the growth rate of the cells, and this effect was potentiated by dexamethasone and counteracted by insulin. (6) The enzyme inductions were similar in exponential and plateau phases of growth, indicating that these processes were independently affected by the three compounds. 相似文献
5.
6.
Plant and Soil - The paper by Korboulewsky and co-authors in this issue of Plant and Soil address some of the central questions of critical zone ecohydrology: how do plants interact with rocks that... 相似文献
7.
Andreas K. Nussler Gianna Vergani Susanne M. Gollin Kenneth Dorko Susanne Gansauge Sidney M. Morris Jr. Antony J. Demetris Minoru Nomoto Hans G. Beger Stephen C. Strom 《In vitro cellular & developmental biology. Animal》1999,35(4):190-197
Summary The isolation and characterization of human liver cell lines are rather difficult due to limited material and poor growth
in cell culture. In this report, we present the isolation, culture and characterization of a new epithelial-like liver cell
line (AKN-1) with a heterogeneous cell population and many characteristics of the biliary epithelium. The AKN-1 cell line
stained positively with antibodies to epithelial cytokeratin polypetides CK 8, 18, and 19. In addition, the cell line expressed
the anti-human epithelial-related antigen (MOC-31), the human epithelial antigen (HEA), and the gamma-glutamyl transpeptidase,
the hematopoietic growth factor, stem cell factor, and also its receptor, c-kit. The cell line failed to express albumin and factor 8 by immunohistochemistry. It did show, however, a twofold increase in
7-ethoxyresorufin-O-deethylase activity. Cytogenetic characterization revealed rare breakpoints in chromosome 2, which to our knowledge, have
not yet been reported in liver cells. 相似文献
8.
Dipl.-Gartenbauing. Dieter Beyme Dr. Werner Ficke Dr. Helmut Kleinhempel Dipl.-Gartenbauing. Hans-Jürgen Schaefer Dipl.-Chemiker. Rolf Bremer 《Archives Of Phytopathology And Plant Protection》2013,46(3):203-211
An lagerndem Winterknoblauch ist unter außenluft‐(x + 6, 5 bzw. 8, 3 °C) und maschinengekühlten Bedingungen (x‐1 . . .‐2 °C) in zwei Lagerperioden die Entwicklung der einzelnen Fäuleerreger verfolgt und in Abhängigkeit von der Lagerdauer statistisch quantifiziert worden. An Hand des Masseanteiles befallener Zwiebeln und der Befallsintensität wird eine zunehmende Ausbreitung von Penicillium spp. und einer Gruppe mit Befall durch mehrere Fäuleerreger unter beiden Lagerbedingungen und von einer Botrytis‐Species (vermutlich B. porri Buchw.) im maschinengekühlten Lager belegt. Fäuleverluste durch Helminthosporium allii Campanile und Bakterien zeigen dagegen mit fortschreitender Lagerdauer einen abnehmenden Verlauf. Mit Eintreten von lagerungsbedingter Seneszenz steigen die Verluste progressiv an. Kaltlagerbedingungen verzögern dagegen ihre Ausbreitung. Die Verluste durch alle Fäulerreger (Fäule gesamt) zeigen eine gleichmäßige Zunahme während der Lagerdauer. 相似文献
9.
A simple method for preparation of methyl-labelled (-) carnitine 总被引:2,自引:0,他引:2
10.
Formation of branched chain acylcarnitines in mitochondria 总被引:5,自引:0,他引:5