|
|
||||||||
Department of 1 Nutrition and Food Sciences and the Biotechnology Center; 3 Department of Biology, Utah State University, Logan, Utah 84322-8700; and 2 Bioorganic and Protein Chemistry, Vitamin D Laboratory, Boston University School of Medicine, Boston, Massachusetts 02118
Antisera were raised against the NH2-terminus of the putative basal lateral membrane (BLM) receptor for 1,25-dihydroxyvitamin D3 [1,25(OH)2D3; BLM-VDR]. In Western analyses of BLM proteins, antibody (Ab) 099 was monospecific for a 64.5-kDa band. A protein of 64.5 kDa was also labeled by the affinity ligand [14C]1,25(OH)2D3-bromoacetate; label was diminished in the presence of excess unlabeled secosteroid. The monoclonal antibody against the nuclear VDR (9A7) failed to detect an appropriate band in BLM fractions. Preincubation of isolated intestinal cells with Ab 099, but not 9A7, affected the following two 1,25(OH)2D3-mediated signal transduction events: augmented intracellular calcium and protein kinase C activity. Subcellular distribution of Ab 099 reactivity by Western analyses and fluorescence microscopy revealed the highest concentrations in BLM followed by the endoplasmic reticulum. Exposure of isolated intestinal cells to 1,25(OH)2D3 for 10 s or vascular perfusion of duodena for 5 min resulted in a time-dependent increase in nuclear localization of the BLM-VDR antigen, as judged by electron microscopy, whereas 24,25-dihydroxyvitamin D3 failed to increase antigenic labeling in nuclei. Densitometric quantitation of Western blots of subcellular fractions prepared from isolated intestinal cells treated with vehicle or 1,25(OH)2D3 confirmed a hormone-induced increase of putative BLM-VDR in the nucleus. It is concluded that a novel cell surface binding protein for 1,25(OH)2D3 has been identified.
steroids; rapid effects; signal transduction; membrane receptor; calcium
This article has been cited by other articles:
![]() |
J. C. Fleet Rapid, Membrane-Initiated Actions of 1,25 Dihydroxyvitamin D: What Are They and What Do They Mean? J. Nutr., December 1, 2004; 134(12): 3215 - 3218. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. M. LOSEL, E. FALKENSTEIN, M. FEURING, A. SCHULTZ, H.-C. TILLMANN, K. ROSSOL-HASEROTH, and M. WEHLING Nongenomic Steroid Action: Controversies, Questions, and Answers Physiol Rev, July 1, 2003; 83(3): 965 - 1016. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Schwartz, V. L. Sylvia, D. Larsson, I. Nemere, D. Casasola, D. D. Dean, and B. D. Boyan 1alpha ,25(OH)2D3 Regulates Chondrocyte Matrix Vesicle Protein Kinase C (PKC) Directly via G-protein-dependent Mechanisms and Indirectly via Incorporation of PKC during Matrix Vesicle Biogenesis J. Biol. Chem., March 29, 2002; 277(14): 11828 - 11837. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Falkenstein, H.-C. Tillmann, M. Christ, M. Feuring, and M. Wehling Multiple Actions of Steroid Hormones---A Focus on Rapid, Nongenomic Effects Pharmacol. Rev., December 1, 2000; 52(4): 513 - 556. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Nemere, D. Larsson, and K. Sundell A specific binding moiety for 1,25-dihydroxyvitamin D3 in basal lateral membranes of carp enterocytes Am J Physiol Endocrinol Metab, September 1, 2000; 279(3): E614 - E621. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |