The molecular mechanism of B cell activation by toll-like receptor protein RP-105

• Main Authors: Mecklenbräuker, Ingrid, Su, I. Hsin, Texido, Gemma, Leitges, Michael, Carsetti, Rita, Rajewsky, Klaus, Miyake, Kensuke, Tarakhovsky, Alexander, Chan, Vivien W. F., Lowell, Clifford A.
• Other Authors: School of Biological Sciences
• Format: Article
• Language: English
• Published: 2011
• Subjects: DRNTU::Science::Biological sciences::Molecular biology
• Online Access: https://hdl.handle.net/10356/93785; http://hdl.handle.net/10220/6798
• Institution: Nanyang Technological University

The B cell–specific transmembrane protein RP-105 belongs to the family of Drosophila toll-like proteins which are likely to trigger innate immune responses in mice and man. Here we demonstrate that the Src-family protein tyrosine kinase Lyn, protein kinase C b I/II (PKC bI/II), and Erk2-specific mitogen-activated protein (MAP) kinase kinase (MEK) are essential and probably functionally connected elements of the RP-105–mediated signaling cascade in B cells. We also find that negative regulation of RP-105–mediated activation of MAP kinases by membrane immunoglobulin may account for the phenomenon of antigen receptor–mediated arrest of RP-105–mediated B cell proliferation.