FRI623 Beta Cell Primary Cilia Mediate Somatostatin Responsiveness Via SSTR3

Disclosure: S.E. Adamson: None. A. Li: None. J. Hughes: None. Somatostatin is an important modulator of beta cell function, but communication between beta and delta cells is not well-understood. Primary cilia are membrane organelles that act as signaling hubs due to their enrichment in certain G-protein coupled receptors and other signaling proteins. We show that somatostatin modulates insulin secretion via somatostatin receptor 3 (SSTR3) located on beta cell primary cilia in mouse islets. SSTR3 and the presence of primary cilia are required for normal beta cell response to somatostatin. Somatostatin signaling leads to beta cell calcium changes, which we characterize here using a beta cell specific genetically-encoded GCaMP6f calcium reporter. Our findings show that ciliary SSTR3 mediates delta to beta cell paracrine crosstalk. Presentation: Friday, June 16, 2023