Local activation of focal adhesion kinase orchestrates the positioning of presynaptic scaffold proteins and Ca2+ signalling to control glucose-dependent insulin secretion

Journal article

A developing understanding suggests that spatial compartmentalisation in pancreatic β cells is critical in controlling insulin secretion. To investigate the mechanisms, we have developed live-cell subcellular imaging methods using the mouse organotypic pancreatic slice. We demonstrate that the organotypic pancreatic slice, when compared with isolated islets, preserves intact β-cell structure, and enhances glucose-dependent Ca²⁺ responses and insulin secretion. Using the slice technique, we have discovered the essential role of local activation of integrins and the downstream component, focal adhesion kinase (FAK), in regulating β cells. Integrins and FAK are exclusively activated at the β-cell capillary interface and using in situ and in vitro models we show their activation both positions presynaptic scaffold proteins, like ELKS and liprin, and regulates glucose-dependent Ca²⁺ responses and insulin secretion. We conclude that FAK orchestrates the final steps of glucose-dependent insulin secretion within the restricted domain where β-cell contact the islet capillaries.

Authors: Jevon, D; Deng, K; Hallahan, N; Kumar, K; Tong, J

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: eLife Sciences Publications
• Journal: eLife
• Volume: 11
• Article number: e76262
• Place of publication: England
• Publication date: 2022-05-13
• Acceptance date: 2022-05-12
• DOI: 10.7554/elife.76262
• EISSN: 2050-084X
• Pmid: 35559734
• Language: English
• Keywords: glucose; insulin-secreting cells; insulin; calcium; islets of Langerhans; focal adhesion protein-tyrosine kinases; integrins; FFR; mice; insulin secretion; vesicular transport proteins