I know a lot of tests on membrane resilience of an organelle or compartment is done by changing osmotic concentrations and measuring various parameters. If I were to do a preliminary test using a gradual dilution of buffers and record percent lysis differences between the control and mutant samples, would that tell me anything? What would be my criteria for choosing the dilutions?
The first ever Nobel Prize in Chemistry was granted to van Hoff for measurements of Osmotic Pressures. His Prize lecture, which can be found on Internet, is still informative for the questions posted.
For testing on the membrane resistance helps knowledge about phenomenon of osmosis
From your brief description I will assume that you do have a way of measuring and comparing percent lysis between differently treated cell-samples exposed to progressively diluted buffers. Progressive dilution of buffers is usually presumed to induce progressive swelling of the cells and subcellular organelles to a point where the cells and organelles burst and lyse. This is correct for some cell types, but by no means all. The response to hypotonic shock varies greatly for different cell types. Some do not lyse at all, and even recover well in culture, COS cells used in phagocytosis tests, for instance. Unfortunately, there is nothing in the literature on the comparative response of different cell types to hypotonic stress, so you may need to explore the particular behaviour of your cell type. You ask if this will tell you anything. This is impossible to anticipate. Let’s assume the best possible outcome, that you do your test blindly and that you detect a clear difference between controls and mutants. This would be encouraging, but to find out if you can get something of biological relevance from this result you would have to embark on a long explorative project with very uncertain outcome. Hypo-osmotic stress and lysis have been usefully applied in very few, intensively investigated instances, particularly with red blood cells.
Thank You for your responses. I understand all the doubts you have raised regarding the outcome from a simple approach and how there are too many variables that need to be taken care of. But assuming that channel densities, pumps etc stay unaffected in between the control and mutants , would an enhanced lysis suggest a difference in membrane composition? I guess in my head that is what i was imagining, since rectifying channels would always complicate the system, i was just hypothesizing differences in lipid constituents leading to a propensity for easy rupture..
- Badges
- Science topic
- Similar topics
- Biological Science
- Cell Biology