The reversible formation of cysteine sulfenic acid promotes B-cell activation and proliferation.
B-cell receptor (BCR) ligation generates reactive oxygen intermediates (ROIs) that play a role in cellular responses. Although ROIs can oxidize all macromolecules, it was unclear which modifications control B-cell responses. In this study, we demonstrate the importance of the first oxidation product of cysteine, sulfenic acid, and its reversible formation in B-cell activation. Upon BCR crosslinking, B cells increase ROI levels with maximal production occurring within 15 min. Increased ROIs preceded elevated cysteine sulfenic acid, which localized to the cytoplasm and nucleus. Analysis of individual proteins revealed that the protein tyrosine phosphatases (PTPs) SHP-1, SHP-2, and PTEN, as well as actin, were modified to sulfenic acid following BCR ligation. Additionally, we used 5,5-dimethyl-1,3-cyclohexanedione (dimedone), a compound that covalently reacts with sulfenic acid to prevent its further oxidation or reduction, to determine the role of reversible cysteine sulfenic acid formation in regulating B-cell responses. Dimedone incubation resulted in a concentration-dependent block in anti-IgM-induced cell division, accompanied by a failure to induce capacitative calcium entry (CCE), and maintain tyrosine phosphorylation. These studies illustrate that reversible cysteine sulfenic acid formation is a mechanism by which B cells modulate pathways critical for activation and proliferation.
Department of Microbiology and Immunology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
Katie E
KE
Crump
Daniel G
DG
Juneau
Leslie B
LB
Poole
Karen M
KM
Haas
Jason M
JM
Grayson
D000199:Actins / Q000378:metabolism; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D049109:Cell Proliferation; D003512:Cyclohexanones / Q000494:pharmacology; D003545:Cysteine / Q000031:analogs & derivatives* / Q000378:metabolism*; D008213:Lymphocyte Activation; D051379:Mice; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000378:metabolism; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000276:immunology*; D011947:Receptors, Antigen, B-Cell
D000199:Actins; D003512:Cyclohexanones; D017382:Reactive Oxygen Species; D011947:Receptors, Antigen, B-Cell; C004774:dimedone; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; C516725:Ptpn11 protein, mouse; C509248:Ptpn6 protein, mouse; D051059:PTEN Phosphohydrolase; C487757:Pten protein, mouse; D003545:Cysteine; C013461:cysteine sulfinic acid