You are using fluorescence microscopy to study a plasma membrane protein that is fused to green fluorescent protein (GFP). Adding GFP to a protein allows us to monitor the protein in live cells using light microscopy without the need for any special stains. Under baseline conditions, the fusion protein is evenly distributed over the surface of the cell. You use the microscope software and laser to photobleach an ROI and watch for the recovery of fluorescence in real time. you have a control protein, a GFP fusion with the insulin receptor, where the ROI fully recovers from photobleaching in 10 min. However, when Protein X is fused with GFP, the fluorescence recovers only to 10% the starting levels in 10 min in the same cell type under the same experimental conditions. Provide two different, reasonable explanations for the different results with these two fusion proteins.

You are using fluorescence microscopy to study a plasma membrane protein that is fused to green fluorescent protein (GFP). Adding GFP to a protein allows us to monitor the protein in live cells using light microscopy without the need for any special stains. Under baseline conditions, the fusion protein is evenly distributed over the surface of the cell. You use the microscope software and laser to photobleach an ROI and watch for the recovery of fluorescence in real time. you have a control protein, a GFP fusion with the insulin receptor, where the ROI fully recovers from photobleaching in 10 min. However, when Protein X is fused with GFP, the fluorescence recovers only to 10% the starting levels in 10 min in the same cell type under the same experimental conditions. Provide two different, reasonable explanations for the different results with these two fusion proteins.

Biomedical Instrumentation Systems

1st Edition

ISBN:9781133478294

Author:Chatterjee

Publisher:Chatterjee

Chapter24: New Technologies And Advances In Medical Instrumentation

Section: Chapter Questions

Problem 10P

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