Show simple item record

dc.contributor.authorRodriguez, Ren_US
dc.contributor.authorMatsuda, Men_US
dc.contributor.authorStorey, Aen_US
dc.contributor.authorKatan, Men_US
dc.identifier.citationBIOCHEMICAL JOURNAL, 2003, 374 pp. 269 - 280en_US
dc.description.abstractStudies of PLCgamma (phospholipase Cgamma) have identified a number of regulatory components required for signalling; however, molecular mechanisms and the relationship between events leading to translocation and an increase of substrate hydrolysis have not been well defined. The addition of a membrane-targeting tag to many signal transducers results in constitutive activation, suggesting that these processes could be closely linked and difficult to dissect. The present study of PLCgamma2 regulation by cross-linking of the BCR (B-cell antigen receptor) or H2O2 stress in DT40 B-cells, demonstrated that the membrane targeting is a separate step from further changes that result in enzyme activation and substrate hydrolysis. Furthermore. we have defined the roles of different domains of PLCgamma2 and, using a panel of cell lines deficient in components linked to PLCgamma2 regulation, the involvement of signalling molecules with respect to each of the steps. We have found that only the lipid-raft-targeted Lyn-PLCgamma2 construct, unlike nonspecific membrane targeting, overcame the requirement for the adapter protein BLNK (B-cell linker). The stable expression of Lyn-PLCgamma2 was not accompanied by an increase in substrate hydrolysis in resting cells, which followed stimulation and specifically required the presence and/or activation of Syk, Btk, phosphoinositide 3-kinase but not BLNK, as established using deficient cell lines or specific inhibitors. Based on mutational analysis of the specific tyrosine residues [Tyr(753) –> Phe (Y753F)/ Y759F] and SH2 (Src homology 2) domains (R564A/R672A) in the context of Lyn-PLCgamma2, we found that Tyr(753)/Tyr(759) were essential, whereas the PLCgamma2 SH2 domains did not have an important role in the transient activation of Lyn-PLCgamma2 but may serve to stabilize an activated form in sustained activation.en_US
dc.format.extent269 - 280en_US
dc.publisherPORTLAND PRESSen_US
dc.titleRequirements for distinct steps of phospholipase C gamma 2 regulation, membrane-raft-dependent targeting and subsequent enzyme activation in B-cell signallingen_US
dc.typeJournal Article
rioxxterms.typeJournal Article/Reviewen_US
dc.relation.isPartOfBIOCHEMICAL JOURNALen_US
pubs.notesaffiliation: Katan, M (Reprint Author), Inst Canc Res, Chester Beatty Labs, Canc Res UK Ctr Cell & Mol Biol, Fulham Rd, London SW3 6JB, England. Inst Canc Res, Chester Beatty Labs, Canc Res UK Ctr Cell & Mol Biol, London SW3 6JB, England. keywords: B-cell signalling; membrane raft; phospholipase activation; phospholipase C gamma 2 (PLC gamma 2); Src homology 2 domain; (SH2 domain); tyrosine phosphorylation keywords-plus: BRUTONS TYROSINE KINASE; C-GAMMA; ANTIGEN RECEPTOR; PLASMA-MEMBRANE; LIPID RAFTS; PHOSPHOINOSITIDE 3-KINASE; CUTTING EDGE; PHOSPHATIDYLINOSITOL 4,5-BISPHOSPHATE; MEDIATED ACTIVATION; CATALYTIC ACTIVITY research-areas: Biochemistry & Molecular Biology web-of-science-categories: Biochemistry & Molecular Biology number-of-cited-references: 54 times-cited: 12 usage-count-last-180-days: 0 usage-count-since-2013: 0 journal-iso: Biochem. J. doc-delivery-number: 714ZF unique-id: ISI:000184945000031 oa: gold_or_bronze da: 2018-09-12en_US
pubs.notesNot knownen_US
pubs.embargo.termsNot knownen_US
dc.contributor.icrauthorKatan, Matildaen_US

Files in this item


There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record