DHHC5 Protein Palmitoylates Flotillin-2 and Is Rapidly Degraded on Induction of Neuronal Differentiation in Cultured Cells

Abstract

Background:The substrates and regulation of DHHC protein palmitoyl acyltransferases (PATs) are largely unknown. Results: Flotillin-2 palmitoylation is abolished in DHHC5 gene-targeted neural stem cells, and neuronal differentiation induces DHHC5 turnover. Conclusion: Flotillin-2 is a substrate for DHHC5, which is regulated at the protein level. Significance: The paper describes an approach to PAT substrate identification and a new PAT regulation mechanism.

Modification of Plasma Membrane Organization in Tobacco Cells Elicited by Cryptogein

“…Similarly, the heterogeneity of RGR values that we observed could correspond to domains of 100 nm or less. Consistent with these observations, single particle tracking experiments performed on Arabidopsis roots to study the dynamics of the PM intrinsic protein PIP2;1 have revealed that about 20% of PIP2;1 fused to GFP exhibited a confined diffusion, with an average confinement range of about 90 nm (Li et al, 2012).…”

“…The depletion of membrane sterols induced by MbCD was observed to result in a disruption to the clustered organization of the protein remorin (Raffaele et al, 2009), indicating the sterol-dependent confinement of this protein into domains of 100 nm. Accordingly, both the clustering in domains of remorin and PIP2;1 were dramatically affected by treatment with cyclodextrin (Raffaele et al, 2009;Li et al, 2012), indicating a major role for sterols in the spatial segregation of these proteins in membrane domains. This treatment also induced an overall increase in acyl chain disorder and a reduction in liquid phase heterogeneity of isolated tobacco PM (Roche et al, 2008), in line with the ability of phytosterols to induce a Lo phase in ternary mixtures of lipids (Beck et al, 2007).…”

“…6). A role for the endocytic pathway in DIM-enriched protein localization at specific sites in root cells and seedlings was accordingly demonstrated for aquaporin (Luu et al, 2012), dynaminrelated protein (Konopka et al, 2008), and flotillin (Li et al, 2012).…”

“…Multidistance spatial cluster statistics analysis (Ripley's k function) of the immunogold-labeled ganglioside GM1 showed spatial aggregation in normal mouse fibroblasts for distances ranging from 32 to 68 nm (Fujita et al, 2007). Similarly, plant-based immunoelectron microscopy experiments have revealed partitioning of both the lipid phosphatidylinositol 4,5-bisphosphate into 25-nm clusters on the PM of tobacco BY2 cells (Furt et al, 2010) and the protein flotillin into clusters of less than 100 nm on the PM of Arabidopsis roots apices (Li et al, 2012). In addition, the protein remorin was observed by immunoelectron microscopy in domains of about 80 nm in the cytosolic leaflet of the membrane of tobacco leaves (Raffaele et al, 2009) and was more recently localized by stimulated emission depletion microscopy within domains of 97 nm in Arabidopsis, whereas the apparent size of these domains was about 250 nm, using classical confocal microscopy (Demir et al, 2013).…”

Function of Flotillins in Receptor Tyrosine Kinase Signaling and Endocytosis: Role of Tyrosine Phosphorylation and Oligomerization

“…N-myristoylation is an irreversible acylation reaction at an N-terminal glycine residue, which is catalyzed by the enzyme Nmyristoyl transferase (51). S-palmitoylation is a reversible reaction, in which the acyl group is transferred to cysteine residues by palmitoyl acyltransferases, referred to as the DHHC family (52,53). In some proteins, e.g.…”