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: 5.96). 06/2007; 176(2):1307-22. DOI: 10.1534/genetics.106.066761
Source: PubMed


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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    • "A useful tool set for monitoring these changes came from the development of 31 YFP-tagged Drosophila Rab proteins, which are overexpressed under UAS control. In addition 27 Rab proteins have been YFP-tagged genomically for the examination of transport at endogenous levels (Dunst et al., 2015; Zhang et al., 2007). Once time-lapse live-imaging movies of fluorescently tagged vesicles are generated, the directionality and velocity of vesicle transport can be measured by the use of kymographs. "
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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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