Blood sugar triggers the secretion of insulin from cells in the pancreas, a process that is impaired in diabetes. A team of Yale researchers have identified a mechanism at the membranes of these pancreatic cells that controls this fundamental function.

The secretion of insulin depends in part upon a lipid transporter protein, TMEM24, which tethers an organelle called the endoplasmic reticulum (ER) to the outer cell membrane. The protein carries lipids created in the ER to the cell membrane to change its composition and allow the secretion of insulin to the exterior of the cell.

The research, published Feb. 17 in the journal Science, provides new insights into mechanisms regulating glucose–responsive insulin release.

This project was a collaboration between the laboratories of cell biology professor Karin Reinisch and chair of neuroscience and cell biology professor Pietro De Camilli. It was carried out by lead authors Joshua Lees, a postdoctoral associate, and Mirko Messa, an associate research scientist.