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Updated: Aug 9, 2026

Isolation of Labile Multi-protein Complexes by in vivo Controlled Cellular Cross-Linking and Immuno-magnetic Affinity Chromatography
Published on: March 10, 2010
Medium chains of adaptor complexes AP-1 and AP-2 recognize leucine-based sorting signals from the invariant chain
1Division of Molecular Cell Biology, Department of Biology, University of Oslo, P. O. Box 1050 Blindern, 0316 Oslo, Norway.
Abstract:
Interactions between tyrosine- and leucine-based sorting signals in the cytoplasmic tails of transmembrane proteins and adaptor complexes AP-1 and AP-2 are believed to be the first step in the formation of clathrin-coated vesicles that deliver these proteins to their destination. Medium chains of AP-1 and AP-2 have been reported to interact with tyrosine-based sorting signals in a number of in vitro assays. In the present study we found that recombinant medium chains could interact with leucine-based sorting signals from the cytoplasmic tail of the invariant chain. Medium chains may therefore be responsible for the proper recognition of both tyrosine and leucine sorting signals by AP-1 and AP-2 complexes.
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