Abstract

Supramolecular cup‐shaped lipoprotein structures called porosomes embedded in the cell plasma membrane mediate fractional release of intravesicular contents from cells during secretion. The presence of porosomes, have been documented in many cell types including neurons, acinar cells of the exocrine pancreas, growth hormone secreting cells of the pituitary, and insulin‐secreting pancreatic beta cells. Mouse insulin‐secreting Min6 cells possess ~100 nm in size porosome complexes, composed of nearly 30 proteins. Isolated Min6 porosomes reconstituted into live Min6 cells demonstrate elevated levels of porosome proteins and an increase in the potency and efficacy of glucose‐stimulated insulin release. Increased glucose‐stimulated insulin secretion up to two days following porosome reconstitution, reflects on the stability and viability of reconstituted porosomes in live cells. These results, establish a new paradigm in porosome‐mediated insulin secretion in beta cells.