Syndecan-1 Mediates Sorting of Soluble Lipoprotein Lipase with Sphingomyelin-Rich Membrane in the Golgi Apparatus.

ABSTRACT: In the secretory pathway, budding of vesicular transport carriers from the trans-Golgi network (TGN) must coordinate specification of lipid composition with selection of secreted proteins. We elucidate a mechanism of soluble protein cargo sorting into secretory vesicles with a sphingomyelin-rich membrane; the integral membrane proteoglycan Syndecan-1 (SDC1) acts as a sorting receptor, capturing the soluble enzyme lipoprotein lipase (LPL) during export from the TGN. Sorting of LPL requires bivalent interactions between LPL and SDC1-linked heparan sulfate chains and between LPL and the Golgi membrane. Physical features of the SDC1 transmembrane domain, rather than a specific sequence, confer targeting of SDC1 and bound LPL into the sphingomyelin secretion pathway. This study establishes that

SUBMITTER: Sundberg EL 

PROVIDER: S-EPMC6832887 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature