Structural Studies Demystify Membrane Protein

Animated structural model of TSPO. Credit: Michigan State University. Mitochondria have proteins that span their membranes to control the flow of messages and materials moving into and out of the organelle. One way scientists can learn more about how membrane proteins function—and how medicines might interact with them—is to determine their structures. But for a variety of reasons, obtaining the structures has been notoriously difficult. Two structural studies have now shed light on the mysterious mitochondrial membrane protein TSPO. This protein plays a key role in transporting cholesterol and drugs into the cell’s mitochondria. While here, the cholesterol is converted to steroid hormones that are essential for numerous bodily functions. Although many researchers have been studying TSPO since the 1990s, they’ve remained uncertain about its mechanisms and how it truly functions. In a study done at Michigan State University, Shelagh Ferguson-Miller and colleagues used X-ray crystallography to determine the structure of TSPO in bacteria models. By doing so, they could visualize where cholesterol potentially binds with the protein, how the two may interact and how that interaction could affect the creation of steroid hormones. The team also identified a TSPO variant that is associated with altered steroid hormone production and anxiety-related diseases. Cholesterol seemed to bind less strongly to this protein, potentially affecting TSPO-cholesterol interactions in mit...
Source: Biomedical Beat Blog - National Institute of General Medical Sciences - Category: Research Authors: Tags: Structural Biology Source Type: blogs