Thirty-One Flavors of Drosophila Rab Proteins

Department of Developmental Biology, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305, USA.
Genetics (Impact Factor: 4.87). 06/2007; 176(2):1307-22. DOI: 10.1534/genetics.106.066761
Source: PubMed

ABSTRACT Rab proteins are small GTPases that play important roles in transport of vesicle cargo and recruitment, association of motor and other proteins with vesicles, and docking and fusion of vesicles at defined locations. In vertebrates, >75 Rab genes have been identified, some of which have been intensively studied for their roles in endosome and synaptic vesicle trafficking. Recent studies of the functions of certain Rab proteins have revealed specific roles in mediating developmental signal transduction. We have begun a systematic genetic study of the 33 Rab genes in Drosophila. Most of the fly proteins are clearly related to specific vertebrate proteins. We report here the creation of a set of transgenic fly lines that allow spatially and temporally regulated expression of Drosophila Rab proteins. We generated fluorescent protein-tagged wild-type, dominant-negative, and constitutively active forms of 31 Drosophila Rab proteins. We describe Drosophila Rab expression patterns during embryogenesis, the subcellular localization of some Rab proteins, and comparisons of the localization of wild-type, dominant-negative, and constitutively active forms of selected Rab proteins. The high evolutionary conservation and low redundancy of Drosophila Rab proteins make these transgenic lines a useful tool kit for investigating Rab functions in vivo.

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Available from: Hugo Bellen, Aug 11, 2015
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    • "UAS-Rab4-RFP Labels early endosome (Sweeney et al. 2006; Zheng et al. 2008) UAS-Spinster-RFP Labels late endosome and lysosome (Sweeney et al. 2006; Zheng et al. 2008) UAS-Rab family (YFP, GFP) Labels endosome and other intracellular trafficking (Zhang et al. 2007) "
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    • "According to a systematic analysis of all Drosophila Rab proteins, Rab26 is expressed specifically in neurons at all developmental stages (larval and pupal development, adults flies) (Chan et al., 2011). To test whether the distribution of Rab26 in Drosophila resembles that in cultured hippocampal neurons, we expressed YFP-tagged versions of wild-type (WT), GTP-preferring (RabQ250L) and GDP-preferring (Rab26T204N) Rab26 using the pan neuronal elav-Gal4 driver (Zhang et al., 2007). Although the tagged Rab26 protein variants were expressed throughout development, no lethality or delayed development was observed (data not shown). "
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    eLife Sciences 02/2015; 4. DOI:10.7554/eLife.05597 · 8.52 Impact Factor
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    • "To provide further evidence that SCs produce CD63- positive exosomes, we modulated the activities of three Rabs previously implicated in exosome secretion: Rab11 (Savina et al., 2002; Koles et al., 2012; Beckett et al., 2013), Rab35 (Hsu et al., 2010), and Rab27 (Ostrowski et al., 2010). Expression of dominant-negative Rab11-YFP (Rab11DN; Zhang et al., 2007), Rab11-RNAi, Rab35-RNAi, and one of two Rab27- RNAi's significantly reduced the number of secreted GFPpositive puncta (Figs. 5 A and S5, A and B). Previous studies have indicated that Rab35 and Rab27 do not regulate secretion of exosomes carrying the cargo receptor Evenness Interrupted (Evi) in Drosophila S2 cells (Koles et al., 2012; Beckett et al., 2013), suggesting multiple exosome secretion routes in flies as well as mammals. "
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