Resumen de Altered response of pendrin-positive intercalated cells in the kidney of Hoxb7-Cre;Mib1f/f mice

Sun-Ah Nam, Wan-Young Kim, Yu-Mi Kim, Hyang Kim, Young-Yun Kong, Sang Mok Lee, Jin Kim

• The anion exchanger pendrin is exclusively expressed by non-type A intercalated cells (ICs), type B ICs and non A-non B ICs. Pendrin-positive ICs are mainly localized in the cortical collecting duct (CCD) and connecting tubule (CNT) rather than the outer medullary collecting duct (OMCD). Our previous study reported that Notch signaling is required for the specification of ureteric bud cells to the principal cells (PCs) and ICs in the medullary collecting duct. The purpose of this study was to determine whether the deletion of Mind bomb-1 (Mib1), an E3 ubiquitin ligase required for the initiation of Notch signaling, would affect the differentiation of pendrin-positive type B and non A-non B ICs in Hoxb7-Cre;Mib1f/f mice. In Hoxb7- Cre;Mib1f/f mice, there was a significant increase in the fraction of pendrin-negative/AE1-positive type A ICs not only in the OMCD (67.02±2.04% vs. 33.78±0.71%;

  Hoxb7-Cre;Mib1f/f vs. Mib1f/f ) but also in the CCD (23.70±2.68% vs. 19.71±0.43%; Hoxb7-Cre;Mib1f/f vs.

  Mib1f/f ) and CNT (23.70±2.68% vs. 19.71±0.43%;

  Hoxb7-Cre;Mib1f/f vs. Mib1f/f ) as compared with Mib1f/f .

  In contrast, there were no significant differences in the fraction of pendrin-positive type B ICs (7.11±3.84% vs.

  7.61±4.45%; Hoxb7-Cre;Mib1f/f vs. Mib1f/f ) between the two groups in the cortex including CCD and CNT.

  Furthermore, there was a significant decrease in the fraction of non A-non B ICs (8.95±2.28% vs.

  Altered response of pendrin-positive intercalated cells in the kidney of Hoxb7-Cre;Mib1f/f mice Sun-Ah Nam1,2, Wan-Young Kim1, Yu-Mi Kim1, Hyang Kim3, Young-Yun Kong4, Sang Mok Lee2 and Jin Kim1 1Department of Anatomy and Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, 2Department of Applied Veterinary Medicine, The Graduate School of Agriculture and Animal Science, Konkuk University, 3Department of Internal Medicine, Division of Nephrology, Kangbuk Samsung Hospital, School of Medicine, Sungkyunkwan University and 4Department of Biological Sciences, Seoul National University, Seoul, Republic of Korea Histol Histopathol (2015) 30: 751-762 DOI: 10.14670/HH-30.751 http://www.hh.um.es Histology and Histopathology Cellular and Molecular Biology Offprint requests to: Jin Kim, MD., Ph.D., Department of Anatomy and Cell Death Disease Research Center, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea, 505, Banpo-Dong, Seocho-Ku, Seoul 137-701, Korea. e-mail: jinkim@catholic.ac.kr 13.06±4.81%; Hoxb7-Cre;Mib1f/f vs. Mib1f/f ) in these tubules in the Hoxb7-Cre;Mib1f/f mice. These results suggest that the degree of differentiation of subtypes of ICs may vary depending on the Notch signaling pathway.