| First Author | Miller H | Year | 2015 |
| Journal | J Cell Biol | Volume | 211 |
| Issue | 6 | Pages | 1193-205 |
| PubMed ID | 26694840 | Mgi Jnum | J:230835 |
| Mgi Id | MGI:5766115 | Doi | 10.1083/jcb.201505030 |
| Citation | Miller H, et al. (2015) Lipid raft-dependent plasma membrane repair interferes with the activation of B lymphocytes. J Cell Biol 211(6):1193-205 |
| abstractText | Cells rapidly repair plasma membrane (PM) damage by a process requiring Ca(2+)-dependent lysosome exocytosis. Acid sphingomyelinase (ASM) released from lysosomes induces endocytosis of injured membrane through caveolae, membrane invaginations from lipid rafts. How B lymphocytes, lacking any known form of caveolin, repair membrane injury is unknown. Here we show that B lymphocytes repair PM wounds in a Ca(2+)-dependent manner. Wounding induces lysosome exocytosis and endocytosis of dextran and the raft-binding cholera toxin subunit B (CTB). Resealing is reduced by ASM inhibitors and ASM deficiency and enhanced or restored by extracellular exposure to sphingomyelinase. B cell activation via B cell receptors (BCRs), a process requiring lipid rafts, interferes with PM repair. Conversely, wounding inhibits BCR signaling and internalization by disrupting BCR-lipid raft coclustering and by inducing the endocytosis of raft-bound CTB separately from BCR into tubular invaginations. Thus, PM repair and B cell activation interfere with one another because of competition for lipid rafts, revealing how frequent membrane injury and repair can impair B lymphocyte-mediated immune responses. |
