PKD2 regulates autophagy and forms a protein complex with BECN1 at the primary cilium of hypothalamic neuronal cells

• Published in: Biochimica et biophysica acta. Molecular basis of disease Vol. 1870; no. 6; p. 167256
• Main Authors: García-Navarrete, Camila, Kretschmar, Catalina, Toledo, Jorge, Gutiérrez, Karla, Hernández-Cáceres, María Paz, Budini, Mauricio, Parra, Valentina, Burgos, Patricia V., Lavandero, Sergio, Morselli, Eugenia, Peña-Oyarzún, Daniel, Criollo, Alfredo
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2024
• Subjects: Animals; Autophagy; Beclin-1; Beclin-1 - metabolism; Cilia - metabolism; Humans; Hypothalamus - cytology; Hypothalamus - metabolism; Mice; Neurons - metabolism; Polycystin-2; Primary cilium; TRPP Cation Channels - genetics; TRPP Cation Channels - metabolism; Beclin-1; Primary cilium; Polycystin-2; Autophagy
• ISSN: 0925-4439; 1879-260X; 1879-260X
• DOI: 10.1016/j.bbadis.2024.167256

The primary cilium, hereafter cilium, is an antenna-like organelle that modulates intracellular responses, including autophagy, a lysosomal degradation process essential for cell homeostasis. Dysfunction of the cilium is associated with impairment of autophagy and diseases known as “ciliopathies”. The discovery of autophagy-related proteins at the base of the cilium suggests its potential role in coordinating autophagy initiation in response to physiopathological stimuli. One of these proteins, beclin-1 (BECN1), it which is necessary for autophagosome biogenesis. Additionally, polycystin-2 (PKD2), a calcium channel enriched at the cilium, is required and sufficient to induce autophagy in renal and cancer cells. We previously demonstrated that PKD2 and BECN1 form a protein complex at the endoplasmic reticulum in non-ciliated cells, where it initiates autophagy, but whether this protein complex is present at the cilium remains unknown. Anorexigenic pro-opiomelanocortin (POMC) neurons are ciliated cells that require autophagy to maintain intracellular homeostasis. POMC neurons are sensitive to metabolic changes, modulating signaling pathways crucial for controlling food intake. Exposure to the saturated fatty acid palmitic acid (PA) reduces ciliogenesis and inhibits autophagy in these cells. Here, we show that PKD2 and BECN1 form a protein complex in N43/5 cells, an in vitro model of POMC neurons, and that both PKD2 and BECN1 locate at the cilium. In addition, our data show that the cilium is required for PKD2-BECN1 protein complex formation and that PA disrupts the PKD2-BECN1 complex, suppressing autophagy. Our findings provide new insights into the mechanisms by which the cilium controls autophagy in hypothalamic neuronal cells. •PKD2 and BECN1 locate at the cilium in N43/5 hypothalamic neuronal cells, and they form a protein complex.•The primary cilium is required for PKD2-BECN1 protein complex formation in N43/5hypothalamic neuronal cells.•PKD2 and cilium are required for autophagy in N43/5 hypothalamic neuronal cells.•PA exposure in N43/5 hypothalamic neuronal cells disrupts the PKD2-BECN1 complex, suppressing autophagy.