Limits...
The small G protein Arl5 contributes to endosome-to-Golgi traffic by aiding the recruitment of the GARP complex to the Golgi.

Rosa-Ferreira C, Christis C, Torres IL, Munro S - Biol Open (2015)

Bottom Line: In addition, in HeLa cells GARP also becomes cytosolic upon depletion of Arl5b.These phenotypes are consistent with a role in endosome-to-Golgi traffic, but are less severe than loss of GARP itself.Thus it appears that Arl5 is one of the factors that directs the recruitment of the GARP complex to the trans-Golgi, and this function is conserved in both flies and humans.

View Article: PubMed Central - PubMed

Affiliation: MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.

No MeSH data available.


Related in: MedlinePlus

Arl5-GFP localizes to the TGN in fly tissues.(A) Confocal micrographs of the duct cells and secretory cells of the L3 larval salivary gland from flies expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. In both tissues, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red). The insets show magnified images of the area indicated by the boxed regions and correspond to merge images of Arl5-GFP (green) and dGolgin-245 staining (red); of Arl5-GFP (green) and dGM130 staining (red) or of all the 3 channels, respectively. Scale bars are 10 µm. (B) Confocal micrographs of epithelial follicle cells from egg chambers at stage 10 of development expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. Again, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red); insets as in (A). Scale bar 10 µm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4400590&req=5

f02: Arl5-GFP localizes to the TGN in fly tissues.(A) Confocal micrographs of the duct cells and secretory cells of the L3 larval salivary gland from flies expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. In both tissues, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red). The insets show magnified images of the area indicated by the boxed regions and correspond to merge images of Arl5-GFP (green) and dGolgin-245 staining (red); of Arl5-GFP (green) and dGM130 staining (red) or of all the 3 channels, respectively. Scale bars are 10 µm. (B) Confocal micrographs of epithelial follicle cells from egg chambers at stage 10 of development expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. Again, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red); insets as in (A). Scale bar 10 µm.

Mentions: To gain further insight into the role of Arl5 in Drosophila we next determined the intracellular location of a GFP-tagged form of the protein. Randomly inserted transgenic UAS-Arl5-GFP lines were generated, and Arl5-GFP was expressed ubiquitously under control of Act5C-GAL4 in flies homozygous for the Arl5KO1 mutation. We first examined the localization of Arl5-GFP in L3 larval salivary glands, a specialized secretory tissue that has been used to study a range of membrane traffic processes. In both the secretory and the duct cells of the salivary gland Arl5-GFP was adjacent to the cis-Golgi marker dGM130 but partially overlapped with the trans-Golgi marker dGolgin-245, thus indicating a location on the trans side of the Golgi (Fig. 2A). Recently, it was shown that Arl1, another member of the Arl family which localizes to the trans-Golgi, plays a role in the salivary gland in both glue granule formation and also the recruitment of the AP-1 clathrin adaptor to the TGN (Torres et al., 2014). However we found no obvious alterations in size and number of granules or in the localization of endogenous AP-1 in the Arl5KO1 mutant, indicating that Arl5 is not required for the sorting mechanisms involved in glue granule biogenesis (supplementary material Fig. S1A,B). We also examined the localization of Arl5-GFP in ovarian follicle cells. Similar to what we observed in salivary glands, in Arl5KO1 mutant follicle cells Arl5-GFP was found adjacent to dGM130 and partially overlapping with dGolgin-245 (Fig. 2B), again suggesting a function at the trans site of the Golgi.


The small G protein Arl5 contributes to endosome-to-Golgi traffic by aiding the recruitment of the GARP complex to the Golgi.

Rosa-Ferreira C, Christis C, Torres IL, Munro S - Biol Open (2015)

Arl5-GFP localizes to the TGN in fly tissues.(A) Confocal micrographs of the duct cells and secretory cells of the L3 larval salivary gland from flies expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. In both tissues, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red). The insets show magnified images of the area indicated by the boxed regions and correspond to merge images of Arl5-GFP (green) and dGolgin-245 staining (red); of Arl5-GFP (green) and dGM130 staining (red) or of all the 3 channels, respectively. Scale bars are 10 µm. (B) Confocal micrographs of epithelial follicle cells from egg chambers at stage 10 of development expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. Again, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red); insets as in (A). Scale bar 10 µm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400590&req=5

f02: Arl5-GFP localizes to the TGN in fly tissues.(A) Confocal micrographs of the duct cells and secretory cells of the L3 larval salivary gland from flies expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. In both tissues, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red). The insets show magnified images of the area indicated by the boxed regions and correspond to merge images of Arl5-GFP (green) and dGolgin-245 staining (red); of Arl5-GFP (green) and dGM130 staining (red) or of all the 3 channels, respectively. Scale bars are 10 µm. (B) Confocal micrographs of epithelial follicle cells from egg chambers at stage 10 of development expressing Arl5-GFP under the control of the Act5C promoter in a Arl5KO1/Arl5KO1 mutant background. Again, Arl5-GFP was found contiguous to the cis-Golgi marker dGM130 (blue) and overlapped with the trans-Golgi marker dGolgin-245 (red); insets as in (A). Scale bar 10 µm.
Mentions: To gain further insight into the role of Arl5 in Drosophila we next determined the intracellular location of a GFP-tagged form of the protein. Randomly inserted transgenic UAS-Arl5-GFP lines were generated, and Arl5-GFP was expressed ubiquitously under control of Act5C-GAL4 in flies homozygous for the Arl5KO1 mutation. We first examined the localization of Arl5-GFP in L3 larval salivary glands, a specialized secretory tissue that has been used to study a range of membrane traffic processes. In both the secretory and the duct cells of the salivary gland Arl5-GFP was adjacent to the cis-Golgi marker dGM130 but partially overlapped with the trans-Golgi marker dGolgin-245, thus indicating a location on the trans side of the Golgi (Fig. 2A). Recently, it was shown that Arl1, another member of the Arl family which localizes to the trans-Golgi, plays a role in the salivary gland in both glue granule formation and also the recruitment of the AP-1 clathrin adaptor to the TGN (Torres et al., 2014). However we found no obvious alterations in size and number of granules or in the localization of endogenous AP-1 in the Arl5KO1 mutant, indicating that Arl5 is not required for the sorting mechanisms involved in glue granule biogenesis (supplementary material Fig. S1A,B). We also examined the localization of Arl5-GFP in ovarian follicle cells. Similar to what we observed in salivary glands, in Arl5KO1 mutant follicle cells Arl5-GFP was found adjacent to dGM130 and partially overlapping with dGolgin-245 (Fig. 2B), again suggesting a function at the trans site of the Golgi.

Bottom Line: In addition, in HeLa cells GARP also becomes cytosolic upon depletion of Arl5b.These phenotypes are consistent with a role in endosome-to-Golgi traffic, but are less severe than loss of GARP itself.Thus it appears that Arl5 is one of the factors that directs the recruitment of the GARP complex to the trans-Golgi, and this function is conserved in both flies and humans.

View Article: PubMed Central - PubMed

Affiliation: MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.

No MeSH data available.


Related in: MedlinePlus