Wiley Acta Medica Okayama 0892-6638 34 12 2020 Dynamin 1 is important for microtubule organization and stabilization in glomerular podocytes 16449 16463 EN The Mon La Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiromi Tachibana Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shun-Ai Li Center for Innovative Clinical Medicine, Okayama University Hospital Tadashi Abe Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sayaka Seiriki Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hikaru Nagaoka Division of Malaria Research, Proteo-Science Center, Ehime University Eizo Takashima Division of Malaria Research, Proteo-Science Center, Ehime University Tetsuya Takeda Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Daisuke Ogawa Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Shin-Ichi Makino Department of Nephrology, Graduate School of Medicine, Chiba University Katsuhiko Asanuma Department of Nephrology, Graduate School of Medicine, Chiba University Masami Watanabe Center for Innovative Clinical Medicine, Okayama University Hospital Xuefei Tian Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine Shuta Ishibe Department of Internal Medicine, Section of Nephrology, Yale University School of Medicine Ayuko Sakane Department of Biochemistry, Tokushima University Graduate School of Medical Sciences Takuya Sasaki Department of Biochemistry, Tokushima University Graduate School of Medical Sciences Jun Wada Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kohji Takei Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroshi Yamada Department of Neuroscience, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Dynamin 1 is a neuronal endocytic protein that participates in vesicle formation by scission of invaginated membranes. Dynamin 1 is also expressed in the kidney; however, its physiological significance to this organ remains unknown. Here, we show that dynamin 1 is crucial for microtubule organization and stabilization in glomerular podocytes. By immunofluorescence and immunoelectron microscopy, dynamin 1 was concentrated at microtubules at primary processes in rat podocytes. By immunofluorescence of differentiated mouse podocytes (MPCs), dynamin 1 was often colocalized with microtubule bundles, which radially arranged toward periphery of expanded podocyte. In dynamin 1-depleted MPCs by RNAi, alpha-tubulin showed a dispersed linear filament-like localization, and microtubule bundles were rarely observed. Furthermore, dynamin 1 depletion resulted in the formation of discontinuous, short acetylated alpha-tubulin fragments, and the decrease of microtubule-rich protrusions. Dynamins 1 and 2 double-knockout podocytes showed dispersed acetylated alpha-tubulin and rare protrusions. In vitro, dynamin 1 polymerized around microtubules and cross-linked them into bundles, and increased their resistance to the disassembly-inducing reagents Ca(2+)and podophyllotoxin. In addition, overexpression and depletion of dynamin 1 in MPCs increased and decreased the nocodazole resistance of microtubules, respectively. These results suggest that dynamin 1 supports the microtubule bundle formation and participates in the stabilization of microtubules. No potential conflict of interest relevant to this article was reported.

PUBLIC LIBRARY SCIENCE Acta Medica Okayama 1932-6203 9 1 2014 Nuclear Hormone Receptor Expression in Mouse Kidney and Renal Cell Lines e85594 EN Daisuke Ogawa Jun Eguchi Jun Wada Naoto Terami Takashi Hatanaka Hiromi Tachibana Atsuko Nakatsuka Chikage Sato Horiguchi Naoko Nishii Hirofumi Makino Nuclear hormone receptors (NHRs) are transcription factors that regulate carbohydrate and lipid metabolism, immune responses, and inflammation. Although several NHRs, including peroxisome proliferator-activated receptor-γ (PPARγ) and PPARα, demonstrate a renoprotective effect in the context of diabetic nephropathy (DN), the expression and role of other NHRs in the kidney are still unrecognized. To investigate potential roles of NHRs in the biology of the kidney, we used quantitative real-time polymerase chain reaction to profile the expression of all 49 members of the mouse NHR superfamily in mouse kidney tissue (C57BL/6 and db/m), and cell lines of mesangial (MES13), podocyte (MPC), proximal tubular epithelial (mProx24) and collecting duct (mIMCD3) origins in both normal and high-glucose conditions. In C57BL/6 mouse kidney cells, hepatocyte nuclear factor 4α, chicken ovalbumin upstream promoter transcription factor II (COUP-TFII) and COUP-TFIII were highly expressed. During hyperglycemia, the expression of the NHR 4A subgroup including neuron-derived clone 77 (Nur77), nuclear receptor-related factor 1, and neuron-derived orphan receptor 1 significantly increased in diabetic C57BL/6 and db/db mice. In renal cell lines, PPARδ was highly expressed in mesangial and proximal tubular epithelial cells, while COUP-TFs were highly expressed in podocytes, proximal tubular epithelial cells, and collecting duct cells. High-glucose conditions increased the expression of Nur77 in mesangial and collecting duct cells, and liver x receptor α in podocytes. These data demonstrate NHR expression in mouse kidney cells and cultured renal cell lines and suggest potential therapeutic targets in the kidney for the treatment of DN. No potential conflict of interest relevant to this article was reported.