The molecular basis for water taste in Drosophila. Nature

Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, CA, USA.
Nature (Impact Factor: 42.35). 04/2010; 465(7294):91-5. DOI: 10.1038/nature09011
Source: PubMed

ABSTRACT The detection of water and the regulation of water intake are essential for animals to maintain proper osmotic homeostasis. Drosophila and other insects have gustatory sensory neurons that mediate the recognition of external water sources, but little is known about the underlying molecular mechanism for water taste detection. Here we identify a member of the degenerin/epithelial sodium channel family, PPK28, as an osmosensitive ion channel that mediates the cellular and behavioural response to water. We use molecular, cellular, calcium imaging and electrophysiological approaches to show that ppk28 is expressed in water-sensing neurons, and that loss of ppk28 abolishes water sensitivity. Moreover, ectopic expression of ppk28 confers water sensitivity to bitter-sensing gustatory neurons in the fly and sensitivity to hypo-osmotic solutions when expressed in heterologous cells. These studies link an osmosensitive ion channel to water taste detection and drinking behaviour, providing the framework for examining the molecular basis for water detection in other animals.

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Available from: Makoto Hiroi, Aug 13, 2014
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    • "Frontiers in Behavioral Neuroscience January 2014 | Volume 8 | Article 6 | 1 BEHAVIORAL NEUROSCIENCE et al., 2004; Al-Anzi et al., 2006; Moon et al., 2006; Dahanukar et al., 2007; Benton et al., 2009; Cameron et al., 2010; Weiss et al., 2011; Miyamoto et al., 2012; Zhang et al., 2013 "
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    • "In Drosophila, ppk receptors have been related with the detection of water, e.g. ppk28 (Cameron et al. 2010, Chen et al. 2010) and salt, e.g. ppk11 and ppk19 (Liu et al. 2003). "
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    Memórias do Instituto Oswaldo Cruz 11/2013; 108 Suppl 1(Suppl 1):63-73. DOI:10.1590/0074-0276130454 · 1.57 Impact Factor
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    • "The repertoire of genes involved in insect gustatory reception is diverse (Liu et al., 2003; Lin et al., 2005; Al-Anzi et al., 2006; Fischler et al., 2007; Mitri et al., 2009; Cameron et al., 2010; Chen et al., 2010; Croset et al., 2010; Kim et al., 2010; Zhang et al., 2013) and includes the large, divergent gene family of Gustatory Receptors (GRs) (Clyne et al., 2000; Dunipace et al., 2001; Scott et al., 2001; Robertson et al., 2003; Isono and Morita, 2010). Membranebound insect GRs are generally expressed in gustatory receptor neurons (GRNs) whose dendritic processes innervate sensory hairs or sensilla distributed on the paired labella, labrum, inner mouthparts , wing margins, genitalia, and tarsal segments of the legs (Dunipace et al., 2001; Scott et al., 2001; Thorne et al., 2004; Wang et al., 2004; Dahanukar et al., 2007). "
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