TY  - GEN
A1  - Püschel, Gerhard Paul
A1  - Christ, Bruno
T1  - Inhibition by PGE₂ of glucagon-induced increase in phosphoenolpyruvate carboxykinase mRNA and acceleration of mRNA degradation in cultured rat hepatocytes
N2  - In cultured rat hepatocytes the key gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PCK) is known to be induced by glucagon via an elevation of cAMP. Prostaglandin E₂ has been shown to antagonize the glucagon-activated cAMP formation, glycogen phosphorylase activity and glucose output in hepatocytes. It was the purpose of the current investigation to study the potential of PGE₂ to inhibit the glucagon-induced expression of PCK on the level of mRNA and enzyme activity. PCK mRNA and enzyme activity were increased by 0.1 nM glucagon to a maximum after 2 h and 4 h, respectively. This increase was completely inhibited if 10 μM PGE2 was added concomitantly with glucagon. This inhibition by PGE₂ of glucagon-induced PCK activity was abolished by pertussis toxin treatment. When added at the maximum of PCK mRNA at 2 h, PGE₂ accelerated the decay of mRNA and reduced enzyme activity. This effect was not reversed by pertussis toxin treatment. Since in liver PGE₂ is derived from Kupffer cells, which play a key role in the local inflammatory response, the present data imply that during inflammation PGE₂ may reduce the hepatic gluconeogenic capacity via a Gᵢ-linked signal chain.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 045 
KW  - Prostaglandin E₂
KW  - Glucagon
KW  - Phosphoenolpyruvate carboxykinase
KW  - Inflammation
KW  - mRNA degradation
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-45792
ER  - 
TY  - THES
A1  - Sin, Celine
T1  - Post-transcriptional control of gene expression
T1  - Post-Transkription Steuerung der Genexpression
N2  - Gene expression describes the process of making functional gene products (e.g. proteins or special RNAs) from instructions encoded in the genetic information (e.g. DNA).  This process is heavily regulated, allowing cells to produce the appropriate gene products necessary for cell survival, adapting production as necessary for different cell environments.  Gene expression is subject to regulation at several levels, including transcription, mRNA degradation, translation and protein degradation.  When intact, this system maintains cell homeostasis, keeping the cell alive and adaptable to different environments.  Malfunction in the system can result in disease states and cell death.  In this dissertation, we explore several aspects of gene expression control by analyzing data from biological experiments.  Most of the work following uses a common mathematical model framework based on Markov chain models to test hypotheses, predict system dynamics or elucidate network topology.  Our work lies in the intersection between mathematics and biology and showcases the power of statistical data analysis and math modeling for validation and discovery of biological phenomena.
N2  - Das „zentrale Dogma der Molekularbiologie“ besagt, dass der Fluss genetischer Information mit der DNS startet, die dann auf die RNS kopiert und in Proteine übersetzt wird (Crick 1970). Dieses System der Informationsübertragung bietet zwei natürliche Eingriffspunkte, an denen Genausprägungen manipuliert werden können -- entweder auf dem Level der mRNS (z.B. durch Kontrolle der Transkriptions- oder mRNS- Degradationsprozesse) oder auf dem Level des Proteins (z.B. durch Kontrolle der Translations- oder Proteindegradationsprozesse). An jedem Eingriffspunkt sind eine Vielzahl unterschiedlicher Prozesse zeitgleich aktiv, um die Konzentrationen von mRNS und Proteinen präzise einzustellen. All diese Prozesse tragen dazu bei, die Zelle intern im stationäzen Zustand zu halten, denn eine Fehlfunktion im System kann zu Krankheitszuständen oder zum Zelltot führen. In dieser Arbeit untersuchen wir verschiedene Aspekte der Kontrolle der Genausprägungs, indem wir Daten biologischer Experimente analysieren. Unsere Arbeit liegt hierbei zwischen den Bereichen der mathematischer Modellierung und der Biologie und zeigt den immensen Nutzen von statistischen Analysemethoden und mathematischer Modellbildung zur Validierung und Neuentdeckung biologischer Phänomene auf.
KW  - mRNA degradation
KW  - protein degradation
KW  - gene expression control
KW  - mathematical modeling
KW  - stochastic modeling
KW  - data analysis and statistics
KW  - next generation sequencing (NGS)
KW  - ribosome
KW  - Datenanalyse und Statistik
KW  - Regulierung der Genexpression
KW  - mRNA Degradierung
KW  - mathematisches Modellierung
KW  - Proteindegradierung
KW  - Ribosom
KW  - stochastische Modellierung
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-102469
ER  -