Lock JG, Hammond LA, Houghton F, Gleeson PA, Stow JL.. E-Cadherin transport from the trans-Golgi network in tubulovesicular carriers is selectively regulated by Golgin-97. Traffic 6: 1142-1156

Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
Traffic (Impact Factor: 4.35). 01/2006; 6(12):1142-56. DOI: 10.1111/j.1600-0854.2005.00349.x
Source: PubMed


E-cadherin is a cell-cell adhesion protein that is trafficked and delivered to the basolateral cell surface. Membrane-bound carriers for the post-Golgi exocytosis of E-cadherin have not been characterized. Green fluorescent protein (GFP)-tagged E-cadherin (Ecad-GFP) is transported from the trans-Golgi network (TGN) to the recycling endosome on its way to the cell surface in tubulovesicular carriers that resemble TGN tubules labeled by members of the golgin family of tethering proteins. Here, we examine the association of golgins with tubular carriers containing E-cadherin as cargo. Fluorescent GRIP domains from golgin proteins replicate the membrane binding of the full-length proteins and were coexpressed with Ecad-GFP. The GRIP domains of p230/golgin-245 and golgin-97 had overlapping but nonidentical distributions on the TGN; both domains were on TGN-derived tubules but only the golgin-97 GRIP domain coincided with Ecad-GFP tubules in live cells. When the Arl1-binding endogenous golgins, p230/golgin-245 and golgin-97 were displaced from Golgi membranes by overexpression of the p230 GRIP domain, trafficking of Ecad-GFP was inhibited. siRNA knockdown of golgin-97 also inhibited trafficking of Ecad-GFP. Thus, the GRIP domains of p230/golgin-245 and golgin-97 bind discriminately to distinct membrane subdomains of the TGN. Golgin-97 is identified as a selective and essential component of the tubulovesicular carriers transporting E-cadherin out of the TGN.

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Available from: John G Lock, Apr 01, 2015
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    • "Golgins are a large family loosely characterized by their Golgi localization and extended coiled coil motifs and have traditionally been associated with maintenance of Golgi structure and assisting bulk flow of proteins through the organelle [16]. Golgin-160 is a vertebrate-specific golgin that is one of only three golgins implicated in trafficking of specific cargoes [15,17–20]. Hicks et al. demonstrated in vitro that the third intracellular loop of β1AR can interact with the N-terminal head domain of golgin-160 in a PIST-independent manner, and that depletion of golgin-160 from HeLa cells decreases the steady state surface levels of exogenously expressed β1AR without affecting internalization rates. "
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    • "In addition, the GRIP domains of both Golgin-245 and Golgin-97 associate with tubular membrane extensions of the trans-Golgi [48]. Moreover, Lock et al. [48] reported that Golgin-97 is involved in trafficking of E-cadherin containing vesicles out of the trans-Golgi. Golgin-97 was shown to play an important role in vesicular transport between the trans-Golgi and the endosome in vitro [49]. "
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