TY - JOUR
T1 - Phosphorylated claudin-16 interacts with Trpv5 and regulates transcellular calcium transport in the kidney
AU - Hou, Jianghui
AU - Renigunta, Vijay
AU - Nie, Mingzhu
AU - Sunq, Abby
AU - Himmerkus, Nina
AU - Quintanova, Catarina
AU - Bleich, Markus
AU - Renigunta, Aparna
AU - Florian Wolf, Matthias Tilmann
N1 - Funding Information:
ACKNOWLEDGMENTS. We thank Dr. Beate Lanske from Harvard Medical School for kindly providing the Ksp-Cre/PTH1Rfl/fl mouse strain. We thank Dr. Krzysztof Hyrc from Washington University Medical School for help with this project. We thank the Washington University Radiation Safety Office for help with [45]Ca++ measurement. This work was supported by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Grants R03DK111776 and P30DK079328 (M.T.F.W.), Children’s Health System, Dallas (M.T.F.W.), and NIDDK grant R01DK084059 (J.H.).
Funding Information:
We thank Dr. Beate Lanske from Harvard Medical School for kindly providing the Ksp-Cre/PTH1Rfl/fl mouse strain. We thank Dr. Krzysztof Hyrc from Washington University Medical School for help with this project. We thank the Washington University Radiation Safety Office for help with [45]Ca++ measurement. This work was supported by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Grants R03DK111776 and P30DK079328 (M.T.F.W.), Children’s Health System, Dallas (M.T.F.W.), and NIDDK grant R01DK084059 (J.H.).
Publisher Copyright:
© 2019 National Academy of Sciences. All rights reserved.
PY - 2019/9/17
Y1 - 2019/9/17
N2 - Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) was previously considered to be a paracellular channelopathy caused by mutations in the claudin-16 and claudin-19 genes. Here, we provide evidence that a missense FHHNC mutation c.908C>G (p.T303R) in the claudin-16 gene interferes with the phosphorylation in the claudin-16 protein. The claudin-16 protein carrying phosphorylation at residue T303 is localized in the distal convoluted tubule (DCT) but not in the thick ascending limb (TAL) of the mouse kidney. The phosphomimetic claudin-16 protein carrying the T303E mutation but not the wildtype claudin-16 or the T303R mutant protein increases the Trpv5 channel conductance and membrane abundance in human kidney cells. Phosphorylated claudin-16 and Trpv5 are colocalized in the luminal membrane of the mouse DCT tubule; phosphomimetic claudin-16 and Trpv5 interact in the yeast and mammalian cell membranes. Knockdown of claudin-16 gene expression in transgenic mouse kidney delocalizes Trpv5 from the luminal membrane in the DCT. Unlike wildtype claudin-16, phosphomimetic claudin-16 is delocalized from the tight junction but relocated to the apical membrane in renal epithelial cells because of diminished binding affinity to ZO-1. High-Ca2+ diet reduces the phosphorylation of claudin-16 protein at T303 in the DCT of mouse kidney via the PTH signaling cascade. Knockout of the PTH receptor, PTH1R, from the mouse kidney abrogates the claudin-16 phosphorylation at T303. Together, these results suggest a pathogenic mechanism for FHHNC involving transcellular Ca2+ pathway in the DCT and identify a molecular component in renal Ca2+ homeostasis under direct regulation of PTH.
AB - Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) was previously considered to be a paracellular channelopathy caused by mutations in the claudin-16 and claudin-19 genes. Here, we provide evidence that a missense FHHNC mutation c.908C>G (p.T303R) in the claudin-16 gene interferes with the phosphorylation in the claudin-16 protein. The claudin-16 protein carrying phosphorylation at residue T303 is localized in the distal convoluted tubule (DCT) but not in the thick ascending limb (TAL) of the mouse kidney. The phosphomimetic claudin-16 protein carrying the T303E mutation but not the wildtype claudin-16 or the T303R mutant protein increases the Trpv5 channel conductance and membrane abundance in human kidney cells. Phosphorylated claudin-16 and Trpv5 are colocalized in the luminal membrane of the mouse DCT tubule; phosphomimetic claudin-16 and Trpv5 interact in the yeast and mammalian cell membranes. Knockdown of claudin-16 gene expression in transgenic mouse kidney delocalizes Trpv5 from the luminal membrane in the DCT. Unlike wildtype claudin-16, phosphomimetic claudin-16 is delocalized from the tight junction but relocated to the apical membrane in renal epithelial cells because of diminished binding affinity to ZO-1. High-Ca2+ diet reduces the phosphorylation of claudin-16 protein at T303 in the DCT of mouse kidney via the PTH signaling cascade. Knockout of the PTH receptor, PTH1R, from the mouse kidney abrogates the claudin-16 phosphorylation at T303. Together, these results suggest a pathogenic mechanism for FHHNC involving transcellular Ca2+ pathway in the DCT and identify a molecular component in renal Ca2+ homeostasis under direct regulation of PTH.
KW - Calcium
KW - Claudin
KW - PTH
KW - Tight junction
KW - Trpv5
UR - http://www.scopus.com/inward/record.url?scp=85072290065&partnerID=8YFLogxK
U2 - 10.1073/pnas.1902042116
DO - 10.1073/pnas.1902042116
M3 - Article
C2 - 31488724
AN - SCOPUS:85072290065
SN - 0027-8424
VL - 116
SP - 19176
EP - 19186
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 38
ER -