Lipid raft-associated β-adducin is required for PSGL-1-mediated neutrophil rolling on P-selectin

Abstract

Lipid rafts, a liquid-ordered plasma membrane microdomain, are related to cell-surface receptor function. PSGL-1, a major surface receptor protein for leukocyte, also acts as a signaling receptor in leukocyte rolling. To investigate the role of lipid raft in PSGL-1 signaling in human neutrophils, we quantitatively analyzed lipid raft proteome of human promyelocytic leukemia cell line HL-60 cells and identified a lipid raft-associated protein β-adducin. PSGL-1 ligation induced dissociation of the raft-associated protein β-adducin from lipid rafts and actin, as well as phosphorylation of β-adducin, indicating a transient uncoupling of lipid rafts from the actin cytoskeleton. Knockdown of β-adducin greatly attenuated HL-60 cells rolling on P-selectin. We also showed that Src kinase is crucial for PSGL-1 ligation-induced β-adducin phosphorylation and relocation. Taken together, these results show that β-adducin is a pivotal lipid raft-associated protein in PSGL-1-mediated neutrophil rolling on P-selectin.

Lipid raft‑associated β‑adducin participates in neutrophil migration

“…The lipid raft is a specialized micro-area structure in the plasma membrane, which consists of a rich of sheath phospholipids and cholesterol ( 22 , 23 ). It has been reported that lipid rafts can regulate cellular signal transduction and the cell membrane dynamics ( 18 ). To investigate whether the integrity of the lipid raft is required for neutrophil migration, cell migratory ability was analyzed with or without integrated lipid raft structure.…”

“…Our previous study ( 18 ) reported that β-adducin, as membrane skeleton protein, has an important role in the process of neutrophil adhesion. In order to determine if β-adducin is involved in the process of neutrophil migration, the distribution of β-adducin was detected using sucrose density gradient centrifugation prior to and following stimulation with fMLP.…”

“…When β-adducin was knocked down in dHL-60, neutrophil migration was inhibited. Xu et al ( 18 ) reported that β-adducin can transfer from the lipid raft area to the cytoplasm, which leads to the cell membrane becoming temporarily disconnected from the actin. The results of the present study demonstrated that during neutrophil migration, β-adducin moves from the cytoplasm to lipid rafts.…”

“…Our previous study demonstrated that β-adducin has an important role in the process of leukocyte rolling and β-adducin as a membrane skeleton protein, acts as a link between the cell membrane and cytoskeleton system. β-adducin can transfer from the lipid raft to the cytoplasm, leading to the cell membrane becoming temporarily disconnected from the cytoskeleton ( 18 ).…”

The actin binding protein α-adducin modulates desmosomal turnover and plasticity

“…Recent work outlined that the transmembrane domain of desmosomal cadherins is larger than that of classical cadherins, which leads to a preference of desmosomal cadherins to locate within the slightly thicker cell membrane present in lipid rafts (Lewis et al, 2019). Interestingly, β-adducin was shown to locate to lipid rafts, too (Xu et al, 2015). As the attenuation of the Dsg3/E-Cad interaction in α-adducin ko cells was only partial, it is possible that α-adducin is also required to sequester desmosomal cadherins within lipid rafts.…”