Author/Editor		Višnjar, Tanja; Chesi, Giancarlo; Iacobacci, Simona; Polishchuk, Elena; Resnik, Nataša; Robenek, Horst; Kreft, Marko; Romih, Rok; Polishchuk, Roman S.; Erdani-Kreft, Mateja
Title		Uroplakin traffic through the Golgi apparatus induces its fragmentation
Type		članek
Vol. and No.		, št. Vol. 7
Publication year		2017
Volume		str. 1-16
ISSN		2045-2322 - Scientific reports
Language		eng
Abstract		Uroplakins (UPs) play an essential role in maintaining an effective urothelial permeability barrier at the level of superficial urothelial cell (UC) layer. Although the organization of UPs in the apical plasma membrane (PM) of UCs is well known, their transport in UCs is only partially understood. Here, we dissected trafficking of UPs and its differentiation-dependent impact on Golgi apparatus (GA) architecture. We demonstrated that individual subunits UPIb and UPIIIa are capable of trafficking from the endoplasmic reticulum to the GA in UCs. Moreover, UPIb, UPIIIa or UPIb/UPIIIa expressing UCs revealed fragmentation and peripheral redistribution of Golgi-units. Notably, expression of UPIb or UPIb/UPIIIa triggered similar GA fragmentation in MDCK and HeLa cells that do not express UPs endogenously. The colocalization analysis of UPIb/UPIIIa-EGFP and COPI, COPII or clathrin suggested that UPs follow constitutively the post-Golgi route to the apical PM. Depolymerisation of microtubules leads to complete blockade of the UPIb/UPIIIa-EGFP post-Golgi transport, while disassembly of actin filaments shows significantly reduced delivery of UPIb/UPIIIa-EGFP to the PM. Our findings show the significant effect of the UPs expression on the GA fragmentation, which enables secretory Golgioutpost to be distributed as close as possible to the sites of cargo delivery at the PM.
Keywords		uroplakins Golgi apparatus fragmentation uroplakini aparat Golgi fragmentacija