Mosquito natriuretic peptide identified as a calcitonin-like diuretic hormone inAnopheles gambiae(Giles)
Author:
Coast Geoffrey M.1, Garside Christopher S.1, Webster Simon G.2, Schegg Kathleen M.3, Schooley David A.3
Affiliation:
1. Department of Biology, Birkbeck (University of London), London WC1E 7HX,UK 2. School of Biological Sciences, University of North Wales, Gwynedd LL57 2UW, UK 3. Biochemistry Department, University of Nevada, Reno, NV 89557,USA
Abstract
SUMMARYMosquito natriuretic peptide (MNP), an uncharacterised peptide from the yellow fever mosquito, Aedes aegypti, acts via cyclic AMP to stimulate secretion of Na+-rich urine by opening a Na+ conductance in the basolateral membrane of Malpighian tubule principal cells. Corticotropin releasing factor (CRF)-related peptides and calcitonin (CT)-like diuretic peptides use cyclic AMP as a second messenger and were therefore considered likely candidates for MNP. BLAST searches of the genome of the malaria mosquito Anopheles gambiae, gave sequences for the CRF-related peptide Anoga-DH44 and the CT-like peptide Anoga-DH31, which were synthesised and tested for effects on Malpighian tubules from An. gambiae and Ae. aegypti,together with 8-bromo-cyclic AMP.The cyclic AMP analogue stimulated secretion of Na+-rich urine by An. gambiae Malpighian tubules, reproducing the response to MNP in Ae. aegypti. It also depolarised the principal cell basolateral membrane voltage (Vb) while hyperpolarising the transepithelial voltage (Vt) to a similar extent.Anoga-DH44 and Anoga-DH31 stimulated production of cyclic AMP, but not cyclic GMP, by Malpighian tubules of An. gambiae. Both peptides had diuretic activity, but only Anoga-DH31 had natriuretic activity and stimulated fluid secretion to the same extent as 8-bromo-cyclic AMP. Likewise, Anoga-DH31 reproduced the effects of cyclic AMP on tubule electrophysiology, whereas Anoga-DH44initially hyperpolarised Vb and depolarised Vt, which is the opposite of the effect of Anoga-DH31.Anoga-DH44 and Anoga-DH31 were also tested for effects on fluid secretion and ion transport by Ae. aegypti tubules. As in An. gambiae, the CRF-related peptide Anoga-DH44 had a non-specific effect on the transport of Na+ and K+,whereas the CT-like peptide Anoga-DH31 specifically stimulated transepithelial Na+ transport.We conclude that the CT-like peptide Anoga-DH31 is the previously uncharacterised mosquito natriuretic peptide.
Publisher
The Company of Biologists
Subject
Insect Science,Molecular Biology,Animal Science and Zoology,Aquatic Science,Physiology,Ecology, Evolution, Behavior and Systematics
Reference30 articles.
1. Beyenbach, K. W. (1995). Mechanism and regulation of electrolyte transport in Malpighian tubules. J. Insect Physiol.41,197-207. 2. Beyenbach, K. W. (2003). Transport mechanisms of diuresis in Malpighian tubules of insects. J. Exp. Biol.206,3845-3856. 3. Beyenbach, K. W. and Petzel, D. H. (1987). Diuresis in mosquitoes: role of a natriuretic factor. News Physiol. Sci.2,171-175. 4. Cabrero, P., Radford, J. C., Broderick, K. E., Costes, L.,Veenstra, J. A., Spana, E. P., Davies, S. A. and Dow, J. A. T.(2002). The Dh gene of Drosophila melanogaster encodes a diuretic peptide that acts through cyclic AMP. J. Exp. Biol.205,3799-3807. 5. Cady, C. and Hagedorn, H. H. (1999a). The effect of putative diuretic factors on in vivo urine production in the mosquito, Aedes aegypti.J. Insect Physiol.45,317-325.
Cited by
81 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|