Temporal regulation of Lsp1 O-GlcNAcylation and phosphorylation duringactivated Bcellsapoptosis

ABSTRACT: Here, we decipher the molecular mechanisms bridging B cell activation and apoptosis mediated by post-translational modification(PTM). We found that O-GlcNAcase inhibition enhances B cell activation and apoptosisinduced by B cell receptor (BCR)cross-linking. This proteome-scale analysis of the functional interplay between protein O-GlcNAcylation and phosphorylation in stimulated mouse primary B cells identified313O-GlcNAcylation-dependent phosphositeson 224 phosphoproteins.Among these phosphoproteins, temporal regulation ofthe O-GlcNAcylation and phosphorylation of lymphocyte-specific protein-1 (Lsp1) is a key switch that triggersapoptosis in activated B cells. O-GlcNAcylation at S209 of Lsp1, identified as the major O-GlcNAc site on Lsp1 by both electron-transfer dissociationand collision-induced dissociationtandem mass spectrometry,was a prerequisite for the recruitment of its kinase, PKC-β1, to induce S243 phosphorylation, leading to ERK activation and down-regulation of BCL-2 and BCL-xL. Thus, we demonstrate the critical PTM interplay of Lsp1 that transmits signals for initiating apoptosis after BCR ligation.

INSTRUMENT(S):

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): B Cell

DISEASE(S): Disease Free

SUBMITTER: Hsin-Yi Wu  

LAB HEAD: Yu-Ju Chen

PROVIDER: PXD003788 | Pride | 2016-09-26

REPOSITORIES: Pride