These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: The beta-glucuronidase klotho exclusively activates the epithelial Ca2+ channels TRPV5 and TRPV6. Author: Lu P, Boros S, Chang Q, Bindels RJ, Hoenderop JG. Journal: Nephrol Dial Transplant; 2008 Nov; 23(11):3397-402. PubMed ID: 18495742. Abstract: BACKGROUND: Active Ca(2+) reabsorption in the kidney is facilitated by the epithelial transient receptor potential vanilloid Ca(2+) channel subtype 5 (TRPV5). The complex-glycosylated TRPV5 is expressed at the apical membrane of the renal distal convoluted tubule (DCT) cells where the pro-urine hormone klotho can stimulate its activity by N-oligosaccharide hydrolysis. This study investigates whether klotho and its closely related analogue, beta-glucuronidase, can activate other renal ion channels than TRPV5 expressed by DCT cells. METHODS: To determine the specificity of this stimulatory effect of klotho and beta-glucuronidase, a selection of ion channels and transporters expressed in the kidney (TRPV4, TRPV5, TRPV6 and TRPM6) was screened in transfected HEK293 cells by using Ca(2+)-influx measurements. RESULTS: Klotho and beta-glucuronidase have been found to significantly increase the activity of TRPV5 and TRPV6, but had no effect on TRPV4 and TRPM6. Furthermore, deglycosylation by endoglycosidase-F also stimulated the activity of TRPV4, TRPV5 and TRPV6, but not of TRPM6. CONCLUSIONS: These results suggest a modulating effect for klotho primarily restricted to the epithelial Ca(2+) channels TRPV5 and TRPV6.[Abstract] [Full Text] [Related] [New Search]