Combined Structural and Functional Imaging of the Kidney Reveals Major Axial Differences in Proximal Tubule Endocytosis
| العنوان: | Combined Structural and Functional Imaging of the Kidney Reveals Major Axial Differences in Proximal Tubule Endocytosis |
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| المؤلفون: | Natsuko Tokonami, Susan Ghazi, Alkaly Gassama, Evgenia Platonova, Marcello Polesel, Urs Ziegler, Andrew M. Hall, Milica Bugarski, Olivier Devuyst, Claus-Dieter Schuh, Dominik Haenni |
| المساهمون: | University of Zurich, Hall, Andrew M |
| المصدر: | Journal of the American Society of Nephrology. 29:2696-2712 |
| بيانات النشر: | Ovid Technologies (Wolters Kluwer Health), 2018. |
| سنة النشر: | 2018 |
| مصطلحات موضوعية: | Male, 0301 basic medicine, 10017 Institute of Anatomy, Intravital Microscopy, Endocytic cycle, 030232 urology & nephrology, 610 Medicine & health, Endosomes, Kidney, Ligands, Endocytosis, 10052 Institute of Physiology, Kidney Tubules, Proximal, Mice, 03 medical and health sciences, 0302 clinical medicine, medicine, Animals, 10035 Clinic for Nephrology, Receptor, 2727 Nephrology, Chemistry, General Medicine, Cell biology, Mice, Inbred C57BL, Low Density Lipoprotein Receptor-Related Protein-2, Protein Transport, Basic Research, 030104 developmental biology, Real-time polymerase chain reaction, medicine.anatomical_structure, Convoluted tubule, Nephrology, 570 Life sciences, biology, Muramidase, 10024 Center for Microscopy and Image Analysis, Lysosomes, Metabolic Networks and Pathways, Immunostaining, Intracellular |
| الوصف: | Background The kidney proximal convoluted tubule (PCT) reabsorbs filtered macromolecules via receptor-mediated endocytosis (RME) or nonspecific fluid phase endocytosis (FPE); endocytosis is also an entry route for disease-causing toxins. PCT cells express the protein ligand receptor megalin and have a highly developed endolysosomal system (ELS). Two PCT segments (S1 and S2) display subtle differences in cellular ultrastructure; whether these translate into differences in endocytotic function has been unknown. Methods To investigate potential differences in endocytic function in S1 and S2, we quantified ELS protein expression in mouse kidney PCTs using real-time quantitative polymerase chain reaction and immunostaining. We also used multiphoton microscopy to visualize uptake of fluorescently labeled ligands in both living animals and tissue cleared using a modified CLARITY approach. Results Uptake of proteins by RME occurs almost exclusively in S1. In contrast, dextran uptake by FPE takes place in both S1 and S2, suggesting that RME and FPE are discrete processes. Expression of key ELS proteins, but not megalin, showed a bimodal distribution; levels were far higher in S1, where intracellular distribution was also more polarized. Tissue clearing permitted imaging of ligand uptake at single-organelle resolution in large sections of kidney cortex. Analysis of segmented tubules confirmed that, compared with protein uptake, dextran uptake occurred over a much greater length of the PCT, although individual PCTs show marked heterogeneity in solute uptake length and three-dimensional morphology. Conclusions Striking axial differences in ligand uptake and ELS function exist along the PCT, independent of megalin expression. These differences have important implications for understanding topographic patterns of kidney diseases and the origins of proteinuria. |
| تدمد: | 1533-3450 1046-6673 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::fa4195725dac85857c2787b00d272f45Test https://doi.org/10.1681/asn.2018050522Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....fa4195725dac85857c2787b00d272f45 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15333450 10466673 |
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