Bevelander, G. S.Pinto, E. S. L. C.Canario, Adelino V. M.Spanings, T.Flik, G.2014-05-122014-05-122008Bevelander, G. S; Pinto, E. S L C; Canario, A. V M; Spanings, T.; Flik, G. CYP27A1 expression in gilthead sea bream (Sparus auratus, L.): effects of calcitriol and parathyroid hormone-related protein, Journal of Endocrinology, 196, 3, 625-635, 2008.0022-0795AUT: ACA00258;http://hdl.handle.net/10400.1/3863Little is known about vitamin D metabolism in fishes. Several reports have shown hydroxylase activities in various organs to produce vitamin D metabolites, but the enzymes involved have not been isolated or characterized. We isolated and characterized a renal mitochondrial hydroxylase, CYP27A1, that governs vitamin D metabolism in gilthead sea bream, Sparus auratus. The enzyme is highly expressed in kidney and to a far lesser extent in liver. When treated with 25-hydroxy vitamin D or calcitriol, the kidney responded differentially and time dependently with CYP27A1 mRNA expression levels. This response substantiates a role for CYP27A1 in fish vitamin D metabolism. This notion is strengthened by upregulation of CYP27A1 in sea bream treated with parathyroid hormone-related protein (PTHrP), and suggests an original role for PTHrP in calcitriol-regulated processes n fish similar to the role of PTH in mammalian vitamin D-dependent processes.engD metabolismFishesjournal article2014-05-08http://dx.doi.org/10.1677/JOE-07-0566