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Characterization of a novel membrane complex required for docking and regulated exocytosis of lysosome-related organelles in Tetrahymena thermophila

ABSTRACT: In the ciliate Tetrahymena thermophila, lysosome-related organelles called mucocysts accumulate at the cell periphery where they secrete their contents in response to extracellular events, a phenomenon termed regulated exocytosis. A forward genetic approach uncovered MDL1 (Mucocyst Discharge with a LamG domain) as essential gene for regulated exocytosis of mucocysts. The encoded protein, Mdl1p, is a 66 kD membrane-associated glycoprotein that localizes to mucocysts, and specifically to a tip domain that contacts the plasma membrane when the mucocyst is docked. Immunoisolation by affinity capture using Mdl1p-FLAG as bait, described here, revealed that Mdl1p forms a complex with 9 other proteins, all of them novel and largely restricted to Alveolates.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Tetrahymena Thermophila Cu428

TISSUE(S): Permanent Cell Line Cell

DISEASE(S): Disease Free

SUBMITTER: Martin Zoltner

LAB HEAD: Dr. Martin Zoltner

PROVIDER: PXD028372 | Pride | 2022-04-06

REPOSITORIES: Pride

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