The cholesterol content of animals cells is carefully regulated. This regulation applies not only ot the overall cholesterol level in the cell, but also to the concentration of cholesterol in the membrane of each organelle. For instance, cholesterol constitutes to almost half of the lipids of the plasma membrane, but less than ten percent of the lipids of the endoplasmic reticulum. Maintaining the proper level and distribution of cholesterol (which is virtually insoluble) requires efficient sensors and transporters. The Radhakrishnan laboratory is interested in understanding the mechanisms by which sensors measure membrane cholesterol and transport proteins move cholesterol between and across membranes. We use all modern tools of biochemistry, biophysics, and cell biology to attack these problems. Students and postdoctoral fellows who are interested in joining our team to tackle this challenging problem are encouraged to contact us.