Fig. 1. Primary cilia play a key role in glucose regulation through active motion.

(A) Proactive motion of primary cilia in islet β cells displays a low frequency of about 0.04 Hz. The movement amplitude increases significantly under a high glucose concentration, which is associated with the calcium response and thereby insulin secretion. (B) The typical structure (top) and architecture of the essential components (bottom) for the proactive beating of motile cilia. Typical primary cilia lack such characteristics. (C) If the β cell cilia display a similar structure to that of most primary cilia, they may not share the same proactive motion mechanism as that of motile cilia. Illustration credit: Ashley Mastin, Science Advances.