The Energy Study Of Nrk Cells During Cytokinesis

Cytokinesis of mammalian cells was a typical mechanical process. Large deformation of cell membrane and assembly of the cytoskeleton (microtubule, actin, myosin) were regulated temporally and spatially during cytokinesis. These behaviors were related to the energy metabolism of cells. ATP, the energy carrier in cells, was the support of the large deformation of cells and cytoskeleton redistribution during cytokinesis. Therefore, to explore the relationship between deformation and energy during cytokinesis was significant.In the present study, flow cytometer and firefly luciferase methods were used to study the behavior of different cell cycle phases of NRK cells. The mechanical process involving cell membrane deformation and cytoskeleton redistribution was explored in the view of energy. The main work and conclusions are as follows:1. Normal rat kidney (NRK) cells were treated with double thymidine block to obtain different cell cycle phases and with serum starvation techniques to obtain ground state cells (G0). The cell cycle phase was detected by Flow cytometer.The total ATP contents of NRK cells was examined using firefly luciferase system and ATP content of M phase was calculated. The result showed that the ATP contents were significantly different in normal cells and ground state cells. NRK cells blocked by thymidine were also significantly different from ground state cells in the ATP contents. After removing the double thymidine about 1h and 4 h, ATP content was remarkably higher than other groups.2. The energy consumption during cell membrane deformation was analyzed on the basis of morphology parameters during cytokinesis. The result indicated that the energy consumption of cell membrane deformation was about 2% of the total energy content during cytokinesis.3. The force and energy consumptions of contractile ring of NRK cells was analyzed from the number of myosin II motor, surface tension in interphase and meridian tension near dividing furrow. The result showed that energy consumptions got from the amount of myosin II motor was about 0.1% of the consumption in NRK cell membrane deformation, and energy from meridian tension near dividing furrow were 10% of the consumption in cell membrane deformation.