Primary cilium alterations and expression changes of Patched1 proteins in niemann-pick type C disease.
Niemann-Pick type C disease (NPC) is a disorder characterized by abnormal intracellular accumulation of unesterified cholesterol and glycolipids. Two distinct disease-causing genes have been isolated, NPC1 and NPC2. The NPC1 protein is involved in the sorting and recycling of cholesterol and glycosphingolipids in the late endosomal/lysosomal system. It has extensive homology with the Patched1 (Ptc1) receptor, a transmembrane protein localized in the primary cilium, and involved in the Hedgehog signaling (Shh) pathway. We assessed the presence of NPC1 and Ptc1 proteins and evaluated the relative distribution and morphology of primary cilia in fibroblasts from five NPC1 patients and controls, and in normal fibroblasts treated with 3-ß-[2-(diethylamino)ethoxy]androst-5-en-17-one (U18666A), a cholesterol transport-inhibiting drug that is widely used to mimic NPC. Immunofluorescence and western blot analyses showed a significant decrease in expression of NPC1 and Ptc1 in NPC1 fibroblasts, while they were normally expressed in U18666A-treated fibroblasts. Moreover, fibroblasts from NPC1 patients and U18666A-treated cells showed a lower percentage distribution of primary cilia and a significant reduction in median cilia length with respect to controls. These are the first results demonstrating altered cytoplasmic expression of Ptc1 and reduced number and length of primary cilia, where Ptc1 is located, in fibroblasts from NPC1 patients. We suggest that the alterations in Ptc1 expression in cells from NPC1 patients are closely related to NPC1 expression deficit, while the primary cilia alterations observed in NPC1 and U18666A-treated fibroblasts may represent a secondary event derived from a defective metabolic pathway.
Department of Medicine, Surgery and Neurosciences, University of Siena, Siena, Italy.
Patrizia
http://orcid.org/0000-0001-9523-4691
P
Formichi
Department of Medicine, Surgery and Neurosciences, University of Siena, Siena, Italy.
Carla
C
Battisti
Department of Pathology AOU Siena, Siena, Italy.
Maria M
MM
De Santi
Department of Pathology AOU Siena, Siena, Italy.
Raffaella
R
Guazzo
Department of Pathology AOU Siena, Siena, Italy.
Sergio A
SA
Tripodi
Department of Medicine, Surgery and Neurosciences, University of Siena, Siena, Italy.
Elena
E
Radi
Department of Pathology AOU Siena, Siena, Italy.
Benedetta
B
Rossi
Unit of Clinic Neurology and Neurometabolic Diseases, AOU Siena, Siena, Italy.
Ermelinda
E
Tarquini
Department of Medicine, Surgery and Neurosciences, University of Siena, Siena, Italy.
Antonio
A
Federico
D000107:Acetylation; D000293:Adolescent; D000328:Adult; D000736:Androstenes / Q000494:pharmacology; D015153:Blotting, Western; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D016022:Case-Control Studies; D002469:Cell Separation; D002478:Cells, Cultured; D002784:Cholesterol / Q000378:metabolism; D002923:Cilia / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D003593:Cytoplasm / Q000378:metabolism; D015536:Down-Regulation; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology; D005372:Filipin / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008875:Middle Aged; D000077296:Niemann-Pick C1 Protein; D052556:Niemann-Pick Disease, Type C / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000072081:Patched-1 Receptor / Q000235:genetics / Q000378:metabolism*; D061251:Primary Cell Culture; D014404:Tubulin / Q000378:metabolism; D055815:Young Adult
D000736:Androstenes; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; C106881:NPC1 protein, human; D000077296:Niemann-Pick C1 Protein; C000606236:PTCH1 protein, human; D000072081:Patched-1 Receptor; D014404:Tubulin; C006261:3-beta-(2-(diethylamino)ethoxy)androst-5-en-17-one; D005372:Filipin; D002784:Cholesterol
NPC1; Patched 1; U18666A; primary cilium