Article

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.

Download full-text

Full-text

Available from: Hugo Bellen, Aug 11, 2015
0 Followers
 · 
126 Views
  • Source
    • "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) "
    [Show abstract] [Hide abstract]
    ABSTRACT: Understanding behavior requires unraveling the mysteries of neurons, glia, and their extensive connectivity. Drosophila has emerged as an excellent organism for studying the neural basis of behavior. This can be largely attributed to the extensive effort of the fly community to develop numerous sophisticated genetic tools for visualizing, mapping, and manipulating behavioral circuits. Here, we attempt to highlight some of the new reagents, techniques and approaches available for dissecting behavioral circuits in Drosophila. We focus on detailing intersectional strategies such as the Flippase-induced intersectional Gal80/Gal4 repression (FINGR), because of the tremendous potential they possess for mapping the minimal number of cells required for a particular behavior. The logic and strategies outlined in this review should have broad applications for other genetic model organisms.
    Journal of Comparative Physiology 04/2015; DOI:10.1007/s00359-015-1010-y · 1.63 Impact Factor
  • Source
    • "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). "
    [Show abstract] [Hide abstract]
    ABSTRACT: eLife digest Our brain contains billions of cells called neurons that form an extensive network through which information is readily exchanged. These cells connect to each other via junctions called synapses. Our developing brain starts off with far more synapses than it needs, but the excess synapses are destroyed as the brain matures. Even in adults, synapses are continuously made and destroyed in response to experiences and learning. Inside neurons there are tiny bubble-like compartments called vesicles that supply the synapses with many of the proteins and other components that they need. There is a growing body of evidence that suggests these vesicles are rapidly destroyed once a synapse is earmarked for destruction, but it is not clear how this may occur. Here, Binotti, Pavlos et al. found that a protein called Rab26 sits on the surface of the vesicles near synapses. This protein promotes the formation of clusters of vesicles, and a membrane sometimes surrounds these clusters. Further experiments indicate that several proteins involved in a process called autophagy—where unwanted proteins and debris are destroyed—may also be found around the clusters of vesicles. Autophagy starts with the formation of a membrane around the material that needs to be destroyed. This seals the material off from rest of the cell so that enzymes can safely break it down. Binotti, Pavlos et al. found that one of the autophagy proteins—called Atg16L—can bind directly to Rab26, but only when Rab26 is in an ‘active’ state. These findings suggest that excess vesicles at synapses may be destroyed by autophagy. Further work will be required to establish how this process is controlled and how it is involved in the loss of synapses. DOI: http://dx.doi.org/10.7554/eLife.05597.002
    eLife Sciences 02/2015; 4. DOI:10.7554/eLife.05597 · 8.52 Impact Factor
  • Source
    • "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. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Male reproductive glands secrete signals into seminal fluid to facilitate reproductive success. In Drosophila melanogaster, these signals are generated by a variety of seminal peptides, many produced by the accessory glands (AGs). One epithelial cell type in the adult male AGs, the secondary cell (SC), grows selectively in response to bone morphogenetic protein (BMP) signaling. This signaling is involved in blocking the rapid remating of mated females, which contributes to the reproductive advantage of the first male to mate. In this paper, we show that SCs secrete exosomes, membrane-bound vesicles generated inside late endosomal multivesicular bodies (MVBs). After mating, exosomes fuse with sperm (as also seen in vitro for human prostate-derived exosomes and sperm) and interact with female reproductive tract epithelia. Exosome release was required to inhibit female remating behavior, suggesting that exosomes are downstream effectors of BMP signaling. Indeed, when BMP signaling was reduced in SCs, vesicles were still formed in MVBs but not secreted as exosomes. These results demonstrate a new function for the MVB-exosome pathway in the reproductive tract that appears to be conserved across evolution.
    The Journal of Cell Biology 08/2014; 206(5). DOI:10.1083/jcb.201401072 · 9.69 Impact Factor
Show more