Khaberni - A research team discovered a new way to understand how bile acids are transferred from the intestines to the blood, an important step within a cycle called enterohepatic circulation, which transfers bile acids between the liver and the intestines to maintain digestive balance and body metabolism.
Bile acids are not only important for fat digestion, but they also act as chemical signals coordinating various body processes.
To understand how they are transported, according to the journal "Nature", researchers focused on a transporter named Ostα/β, responsible for transferring bile acids from intestinal cells into the bloodstream, but its mechanism was unknown.
Using advanced techniques such as cryo-electron microscopy, molecular motion simulation, and electrical analysis, scientists found that Ostα/β consists of four small units, each with a unique shape that allows it to handle bile acids.
There is a special groove inside the transporter that holds the molecules, creating a suitable environment for them within the cell membrane, while a hydrophilic tunnel allows the passage of bile acids in a manner dependent on electric voltage and molecule concentration.
The results clarify that Ostα/β functions as a bidirectional transporter, meaning it can transport bile acids in both directions as needed; this helps the body maintain a balance of bile acids between the intestines, blood, and liver.
This discovery is significant; it opens the door to studying other poorly understood membrane proteins and understanding how the fatty environment surrounding the cell affects the function of these vital transporters.
