Protein sorting in the Golgi complex: shifting paradigms.
The paradigms for transport along the biosynthetic route have changed dramatically over the past 15 years. Unlike the situation 15 years ago, the current paradigm involves sorting signals practically at every step of the pathway. In particular, at the exit from the Golgi complex, apical, basolateral and lysosomal targeting signals result in the generation of a variety of routes. Furthermore, it is now quite clear that not all sorting in the biosynthetic route occurs in the Golgi complex or the Trans Golgi Network (TGN). Sorting may occur distally to the Golgi, in recycling endosomes or in budded tubulosaccular structures, or it may occur proximally to the Golgi complex, at the exit from the ER. Several adaptors are candidates to sort apical and basolateral proteins but only AP1B and AP4 are currently involved. Progress is fast and future work should elucidate many of the open questions.
Rodriguez-Boulan
Enrique
E
Margaret Dyson Vision Research Institute, Weill Medical College of Cornell University, LC-300, 1300 York Avenue, New York, NY 10021, USA. boulan@med.cornell.edu
Müsch
Anne
A
D033942:Adaptor Proteins, Vesicular Transport / Q000737:chemistry / Q000378:metabolism*; D002966:Clathrin / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D005089:Exocytosis / Q000502:physiology*; D006056:Golgi Apparatus / Q000378:metabolism*; D021962:Membrane Microdomains / Q000378:metabolism; D008954:Models, Biological; D021382:Protein Sorting Signals; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D015398:Signal Transduction; D021601:trans-Golgi Network / Q000378:metabolism*
D033942:Adaptor Proteins, Vesicular Transport; D002966:Clathrin; D021382:Protein Sorting Signals