Julian T Dow

..We applied such an analysis to Drosophila melanogaster Malpighian (renal) tubule, a defined differentiated tissue...

..Here, our goal was to identify genes that display transcriptional variation between laboratory strains of Drosophila melanogaster, and to explore evidence of gender-biased interactions underlying that variability...

..These results, while providing the first gene knockouts of V-ATPases in animals, also illustrate the general utility of D. melanogaster as a model for the genetic analysis of ion transport and its control in epithelia...

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..The tubule can thus bask in a greatly enhanced reputation as a key tissue for an unexpectedly wide range of functions in the insect...

..A report on the XXXV International Congress of Physiological Sciences, held together with Experimental Biology 2005, San Diego, USA, 31 March - 6 April 2005...

..The results have provided new insights into neuroendocrine control in Drosophila and other organisms...

..This is illustrated in the context of Drosophila. In this case, it seems as if a shift from developmental biology to transport physiology and metabolism will be required to provide a more balanced skills base for post-genomics...

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..With the use of the beautiful genetic tools and extensive genomic resources characteristic of this genetic model, it has been possible to gain unique insights into the structure, function, and control of epithelia...

..The actions of capa-1 and capa-2 are not synergistic, implying that both act on the same pathways in tubules. The capa gene is thus the first to be shown to encode neuropeptides that act on renal fluid production through nitric oxide...

..Immunocytochemical localisation reveals that White is expressed in intracellular vesicles in tubule principal cells, suggesting that White participates in vesicular transepithelial transport of cGMP...

..IP(3)R contributes to the calcium signalling cascades initiated by these peptides in both principal and stellate cells...

..SPoCk thus contributed to both of the contrasting requirements for Ca2+ in transporting epithelia: to transport or store Ca2+ in bulk without compromising its use as a signal...

..Finally, we show the generality of capa peptide action, to stimulate NO/cGMP signalling and increase fluid transport, across the Diptera, but not in the more primitive Orthoptera...

..The results highlight the dynamic nature and both spatial and temporal heterogeneity of calcium signaling possible in differentiated, organotypic cells and provide a new model for neuroendocrine control of V-ATPase...

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..This shows that, although detoxification enzymes are widely distributed, baseline protection against DDT resides primarily in the insect excretory system, corresponding to less than 0.1% of the mass of the organism...

..These results coincide with the expression view of the gene family, in which 13 of the genes are specialized for epithelial roles, whereas others have spatially or temporally restricted patterns of expression...

..Accordingly, CG2196 was renamed salty dog (salt)...

..These data show that the Na(+),K(+) ATPase, previously thought to be unimportant, may be as vital in insect tissues as in vertebrates, but can be cryptic to conventional pharmacology...

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..The transgene also provides a generic tool for the analysis of cGMP signaling in Drosophila...

..Thus, both CG10806 and CG31052 are functionally members of the CPA2 gene family, colocalise to the same apical membrane as the plasma membrane V-ATPase and show distinct ion specificities, as expected for the Wieczorek exchanger...

..Glibenclamide thus interacts with tubule in three separate ways; as a potent inhibitor of fluid secretion, as an inhibitor (possibly competitive) of an organic solute transporter and as a substrate for excretion and metabolism...

..The physiological impacts of defective ANT expression are thus widespread and diverse...

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..Finally, a scaffolding component of the TRPL/TRP-signaling complex, INAD, is not expressed in tubules, suggesting that inaD is not essential for TRPL/TRP function in Drosophila tubules...

..These classical Drosophila mutants thus identify residues that are essential for function in organisms with wide phylogenetic separation...

..These tissues also displayed elevated calcium in response to Drosokinin, demonstrating novel roles for leucokinin. A functional genomic approach has thus yielded the first complete characterization of a leucokinin receptor in an insect...

..Finally, targeted over-expression of either debcl or buffy to tubule principal cells does not impact on tubule caspase-9 activity. Thus, IP(3)K-1 modulates epithelial cell apoptosis without involvement of bcl-2-type proteins...

..The results uncovered a new role for cGMP signaling in tubule and also demonstrate the utility of the tubule as a possible in vivo test bed for novel receptors, ligands, or agonists/antagonists...

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..These cells also express receptors for leucokinin, another major diuretic peptide, implying that the cells may be important in homeostatic regulation...

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..In this article, we discuss several approaches in which model-organism genomics and proteomics could be applied to the identification and validation of novel targets for antiparasitic drug discovery in veterinary medicine...

..The orthodoxy that stellate cells are unique to, and general among, Diptera may thus require revision...

..12+/-0.06 microM for PDE11). We provide the first characterization of a cGMP-specific PDE and two dual-specificity PDEs in Drosophila, and show a high degree of similarity in structure and function between human and Drosophila PDEs...

..The demonstration that they are readily compatible with metabolomic approaches is particularly important for systems approaches to metabolic pathways...

..In addition, the structure of a new class of lipid with a histidine head group, found in all of the strains of flies, but lower in Maroon Like, was elucidated...

..This result is consistent with the homology between DRIP and mammalian water-specific AQPs. Together, these data establish Drosophila as a new model system with which to investigate AQP function...