A Novel Cell-Cell Communication Structure: Tanycyte and Cilia Hypothalamic Unifying Glia-cilia Structure (HUGS)

Primary cilia, microtubule-based sensory organelles that mediate cell-cell communication, may facilitate signaling in the brain through direct physical contacts (e.g., synapse-like structures). Similarly, specialized glial cells lining the third ventricle (3V) called tanycytes signal through physical interactions and can dynamically alter their morphology in response to external stimuli and physiological changes. Here, we identify robust cilia-tanycyte contacts; we term HUGS ( H ypothalamic, U nifying G lia-cilia S tructures) and discover that these connections are disrupted in a mouse ciliopathy model ( Bbs4 ) exhibiting hypothalamic dysfunction. These data provide insight into potentially new cell-cell signaling mechanisms deployed by neuronal cilia. .