Showing papers by "Klaus Fiedler published in 1993"
TL;DR: It is proposed that in vivo the CHAPS and Triton complexes form part of a sorting platform that mediates protein segregation and delivery to the apical cell surface.
Abstract: In simple epithelial cells, the delivery of apical and basolateral proteins to the cell surface is mediated by sorting in the trans-Golgi network and transport via separate vesicular carriers In order to identify the molecular machinery involved in protein sorting, we have recently studied a detergent-insoluble complex in Madin-Darby canine kidney (MDCK) cells, following CHAPS extraction of exocytic carrier vesicles, specifically including the apical marker protein influenza hemagglutinin (HA) Previously, a Triton X-100 insoluble membrane residue that was enriched in glycosylphosphatidylinositol-anchored (GPI) proteins and glycolipids was characterized and implicated in transport to the apical cell surface [Brown, D, & Rose, J (1991) Cell 68, 533-544] In this report, the protein compositions of the CHAPS and Triton complexes have been compared by two-dimensional gel analysis Only a few major membrane proteins are found in the complexes The protein compositions are qualitatively similar, but differ quantitatively in the individual components The CHAPS complex is depleted of GPI-linked proteins and retains a minor fraction of lipids similar in composition to that of the Triton X-100 insoluble complex We propose that in vivo the complexes form part of a sorting platform that mediates protein segregation and delivery to the apical cell surface
243 citations