Rt-pcr microlocalization of mrnas for calbindin-d28k and vitamin d
receptor in the murine nephron.
Liu, Lanting, Anupa Khastgir, Jon M. McCauley, S. Terence Dunn, James
H. Morrissey, Sylvia Christakos, Mark R. Hughes, and James E.
Bourdeau.
Departments of Medicine (Section of Nephrology), Pathology, and
Physiology & Biophysics, University of Oklahoma Health Sciences
Center, and Medical Service, Department of Veterans Affairs Medical
Center, Oklahoma City, Oklahoma 73104, Cardiovascular Biology
Program, Oklahoma Medical Research Foundation, Oklahoma City,
Oklahoma 73104, National Center for Human Genome Research, National
Institutes of Health, Bethesda, Maryland 20892, Department of
Biochemistry and Molecular Biology, University of Medicine and
Dentistry-New Jersey Medical School, Newark, New Jersey 07103
APStracts 2:0207F, 1995.
The spatial relationship between vitamin D receptor (VDR) and
calbindin-D28k (CaBP-D28k) gene expression within the murine kidney
was studied by localizing their mRNAs in discrete nephron structures
using reverse transcription-polymerase chain reaction (RT-PCR).
Primers for [beta]-actin mRNA were used as a control for the presence
of tissue during RT-PCR for CaBP-D28k mRNA. Messenger RNA for CaBP
-D28k was found only in distal convoluted tubules (DCTs), connecting
tubules (CNTs), and cortical collecting ducts (CCDs). In contrast,
VDR mRNA was detected in glomeruli, segment 2 proximal convoluted
tubules, cortical thick ascending limbs of Henle's loop, DCTs, CNTs,
and initial CCDs. The presence of both VDR and CaBP-D28k mRNA in
DCTs, CNTs, and CCDs is consistent with the hypothesis that
calcitriol acts via the VDR to stimulate CaBP-D28k synthesis.
Conversely, the presence of VDR mRNA in other parts of the nephron
suggests that calcitriol has genomically-mediated actions within the
kidney in addition to stimulation of CaBP-D28k synthesis.
Received 7 June 1995; accepted in final form 27 November 1995.
APS Manuscript Number F184-5.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 8 December 95