Loading…
Model Organisms: New Insights Into Ion Channel and Transporter Function.: L-type calcium channels regulate epithelial fluid transport in Drosophila melanogaster
Institute of Biomedical and Life Sciences, Division of Molecular Genetics, University of Glasgow, Glasgow G11 6NU, United Kingdom The neuropeptide CAP 2b stimulates fluid transport obligatorily via calcium entry, nitric oxide, and cGMP in Drosophila melanogaster Malpighian (renal) tubules. We have s...
Saved in:
Published in: | American Journal of Physiology: Cell Physiology 2001-02, Vol.280 (2), p.C394-C407 |
---|---|
Main Authors: | , , , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Institute of Biomedical and Life Sciences, Division of Molecular
Genetics, University of Glasgow, Glasgow G11 6NU, United
Kingdom
The neuropeptide CAP 2b stimulates
fluid transport obligatorily via calcium entry, nitric oxide, and cGMP
in Drosophila melanogaster Malpighian (renal) tubules. We
have shown by RT-PCR that the Drosophila L-type calcium
channel 1 -subunit genes Dmca1D and
Dmca1A ( nbA ) are both expressed in tubules.
CAP 2b -stimulated fluid transport and cytosolic calcium
concentration ([Ca 2+ ] i ) increases are
inhibited by the L-type calcium channel blockers verapamil and
nifedipine. cGMP-stimulated fluid transport is verapamil and nifedipine
sensitive. Furthermore, cGMP induces a slow
[Ca 2+ ] i increase in tubule principal cells
via verapamil- and nifedipine-sensitive calcium entry; RT-PCR shows
that tubules express Drosophila cyclic nucleotide-gated
channel ( cng ). Additionally, thapsigargin-induced [Ca 2+ ] i increase is verapamil sensitive.
Phenylalkylamines bind with differing affinities to the basolateral and
apical surfaces of principal cells in the main segment; however,
dihydropyridine binds apically in the tubule initial segment.
Immunocytochemical evidence suggests localization of
1 -subunits to both basolateral and apical surfaces of
principal cells in the tubule main segment. We suggest roles for L-type
calcium channels and cGMP-mediated calcium influx in both calcium
signaling and fluid transport mechanisms in Drosophila .
calcium channel 1 -subunits; targeted aequorin
expression; intracellular calcium; guanosine 3',5'-cyclic
monophosphate; cyclic nucleotide-gated channels |
---|---|
ISSN: | 0363-6143 1522-1563 |
DOI: | 10.1152/ajpcell.2001.280.2.c394 |