The vertebrate primary cilium is a sensory organelle

UMMS Affiliation

Department of Cell Biology; Program in Molecular Medicine



Document Type



Animals; Calcium Channels; Cell Membrane; Cilia; Eukaryotic Cells; Humans; Kidney; Membrane Proteins; Receptors, Cell Surface; Signal Transduction; TRPP Cation Channels


The primary cilium is a generally non-motile cilium that occurs singly on most cells in the vertebrate body. The function of this organelle, which has been the subject of much speculation but little experimentation, has been unknown. Recent findings reveal that the primary cilium is an antenna displaying specific receptors and relaying signals from these receptors to the cell body. For example, kidney primary cilia display polycystin-2, which forms part of a Ca2+ channel that initiates a signal that controls cell differentiation and proliferation. Kidney primary cilia also are mechanosensors that, when bent, initiate a Ca2+ signal that spreads throughout the cell and to neighboring cells. Primary cilia on other cell types specifically display different receptors, including those for somatostatin and serotonin.

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Citation: Curr Opin Cell Biol. 2003 Feb;15(1):105-10.

Related Resources

Link to Article in PubMed

Journal Title

Current opinion in cell biology

PubMed ID