ARAP1 fine-tunes F-actin polymerization level in lymphocytes through RhoA inhibition.

ABSTRACT: Rho family of small GTPases play crucial roles in F-actin polymerization and actomyosin contractility, facilitating lymphocyte polarization, motility, and adhesion. However, the spatiotemporal cooperation of these processes remains unclear. In this study, we found that the dual GTPase-activating protein (GAP) ankyrin repeat and PH domain 1 (ARAP1) modulates RhoA activity through its Ras-association (RA) domain, which binds to Rac and Rap1 and is critical for F-actin polymerization and cell migration. ARAP1 was transiently recruited to cell protrusions following chemokine stimulation. ARAP1-deficient cells exhibited enhanced chemokine-directed migration, accompanied by increased RhoA activation and F-actin polymerization. Conversely, ARAP1 overexpression had the opposite effect and inhibite

SUBMITTER: Ueda Y 

PROVIDER: S-EPMC12756398 | biostudies-literature | 2025

REPOSITORIES: biostudies-literature