title: Calcium-binding protein (28,000 Mr calbindin-D28k) in kidneys of the bullfrog Rana catesbeiana during metamorphosis.
abstract: A protein of approximately 28,000 relative molecular mass (Mr) cross-reacting with antiserum against the 28,000-Mr rat renal calcium-binding protein (calbindin-D28k) has been localized in the kidney of a salientian amphibian, Rana catesbeiana. Cells reactive for calbindin-D28k were found in the distal tubule at all stages of metamorphosis by the unlabeled antibody peroxidase-antiperoxidase technique. Adult kidneys appeared to have more calbindin-D28k-positive cells. The renal corpuscle, neck, and proximal tubule were negative. An immunoreactive 28,000-Mr band that comigrated with the band of calbindin-D28k was visualized by the immunoblot technique. The finding of the 28,000-Mr calbindin-D in the anamniotic kidney demonstrates that this calcium-binding protein (CaBP) is phylogenetically older than our previous studies of higher vertebrates had revealed (Rhoten et al., 1985). Although the function of calbindin-D28k in the distal nephron is unknown, this CaBP can now be presumed to have functional significance in the mesonephric as well as the metanephric kidney.
mesh_terms: D000818:Animals; D064092:Calbindin 1; D064026:Calbindins; D006651:Histocytochemistry; D007668:Kidney / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D007686:Kidney Tubules, Distal / Q000378:metabolism / Q000648:ultrastructure; D008675:Metamorphosis, Biological; D008854:Microscopy, Electron; D008970:Molecular Weight; D011892:Rana catesbeiana; D064030:S100 Calcium Binding Protein G / Q000378:metabolism*
chemical_list: C576500:Calb1 protein, rat; D064092:Calbindin 1; D064026:Calbindins; D064030:S100 Calcium Binding Protein G