Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Vishnu, N.
Development, Characterization and Application of a genetically encoded fluorescent sensor for quantifying ATP Dynamics within the Endoplasmic Reticulum
PhD-Studium (Doctor of Philosophy); Humanmedizin; [ Dissertation ] Medical University of Graz; 2014. pp. 99
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- Autor*innen der Med Uni Graz:
- Vishnu Neelanjan
- Betreuer*innen:
- Graier Wolfgang
- Malli Roland
- Altmetrics:
- Abstract:
- The endoplasmic reticulum (ER) is a central organelle which is used for carrying out cellular functions such as protein folding, post translational modifications of proteins, degradation and protein secretion. Most of these process need ATP binding and or hydrolysis. In this project a genetically encoded FRET based fluorescent ATP biosensor was designed and targeted into the lumen of the ER. Using this biosensor an inverse correlation between ER Ca2+ mobilization and an elevation of ER ATP levels was observed which is independent of the mode of ER Ca2+ release. Experiments further demonstrated that this Ca2+ coupled ER ATP rise is highly sensitive to AMP dependent protein kinase (AMPK) and autophagy. In addition it was seen that in the cancer cells ER could fulfill its energy requirements by shifting from glycolysis to oxidative phosphorylation (OXPHOS) as central ATP generation system in the conditions of nutrient starvation. Moreover, experiments revealed that the ER needs continuous supply of ATP for carrying out its biological functions and thus requires a well regulated ER ATP transport system. A computational biology based approach has been applied in order to identify some of the proteins that might be regulating ER ATP transport. It is believed that an understanding of the physiological significance of ER ATP transport mechanisms and their regulation will help in a long way in realizing the pathological consequences associated with protein misfolding and cellular regulation of cancer. This in long term could become a novel paradigm for therapeutic drug development.