Direct Binding of Rap1 to Talin1 and to MRL Proteins Promotes Integrin Activation in CD4⁺ T Cells.

ABSTRACT: Agonist-induced Rap1 GTP loading results in integrin activation involved in T cell trafficking and functions. MRL proteins Rap1-interacting adapter molecule (RIAM) and lamellipodin (LPD) are Rap1 effectors that can recruit talin1 to integrins, resulting in integrin activation. Recent work also implicates direct Rap1-talin1 interaction in integrin activation. Here, we analyze in mice the connections between Rap1 and talin1 that support integrin activation in conventional CD4⁺ T (Tconv) and CD25^HiFoxp3⁺CD4⁺ regulatory T (Treg) cells. Talin1(R35E, R118E) mutation that disrupts both Rap1 binding sites results in a partial defect in α_Lβ₂, α₄β₁, and α₄β₇ integrin activation in both Tconv

SUBMITTER: Lagarrigue F 

PROVIDER: S-EPMC9644409 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature