King's College London

Research portal

The Rho family GEF FARP2 is activated by aPKCι to control tight junction formation and polarity

Research output: Contribution to journalArticle

Ahmed Elbediwy, Yixiao Zhang, Mathias Cobbaut, Philippe Riou, Ray S. Tan, Selene K. Roberts, Chris Tynan, Roger George, Svend Kjaer, Marisa L. Martin-Fernandez, Barry J. Thompson, Neil Q. McDonald, Peter J. Parker

Original languageEnglish
Article numberjcs223743
JournalJournal of Cell Science
Issue number8
Early online date14 Mar 2019
Publication statusPublished - Apr 2019

King's Authors


The elaboration of polarity is central to organismal development and to the maintenance of functional epithelia. Among the controls determining polarity are the PAR proteins, PAR6, aPKCι and PAR3, regulating both known and unknown effectors. Here, we identify FARP2 as a 'RIPR' motif-dependent partner and substrate of aPKCι that is required for efficient polarisation and junction formation. Binding is conferred by a FERM/FA domain-kinase domain interaction and detachment promoted by aPKCι-dependent phosphorylation. FARP2 is shown to promote GTP loading of Cdc42, which is consistent with it being involved in upstream regulation of the polarising PAR6-aPKCι complex. However, we show that aPKCι acts to promote the localised activity of FARP2 through phosphorylation. We conclude that this aPKCι-FARP2 complex formation acts as a positive feedback control to drive polarisation through aPKCι and other Cdc42 effectors.

View graph of relations

© 2018 King's College London | Strand | London WC2R 2LS | England | United Kingdom | Tel +44 (0)20 7836 5454