Ras-related protein Rap-1 (Rap1) (Rap1)

Ras-related protein Rap-1 (Rap1) is a small GTPase belonging to the Ras superfamily that functions as a molecular switch, cycling between an active GTP-bound state and an inactive GDP-bound state [UniProt P62834, P61224]. It exists in two highly homologous isoforms, Rap1A and Rap1B, which are essential for regulating cell adhesion, integrin activation, and the formation of cell-cell junctions [PubMed 21810917]. Rap 1 plays a pivotal role in platelet aggregation and leukocyte trafficking, making it a central mediator of hemostasis and inflammatory responses [PubMed 21810917]. In oncology, Rap 1 is frequently dysregulated, contributing to tumor cell invasion, metastasis, and angiogenesis by modulating the cytoskeleton and signaling pathways like MAPK/ERK [PubMed 25633017]. While direct small-molecule inhibitors of Rap 1 are currently a focus of preclinical research, therapeutic strategies often involve targeting its regulators, such as Exchange Proteins directly Activated by cAMP (EPAC), or inhibiting its post-translational prenylation using geranylgeranyltransferase inhibitors [PubMed 11884415, 22532568]. Additionally, a distinct protein also named Rap1 (TERF2IP) serves as a component of the shelterin complex, protecting telomeres and modulating NF-kappaB signaling, though the GTPase isoforms are the primary focus of current drug development efforts [UniProt Q9NY60].

Other names

Ras-proximate-1KREV-1RAP1ARAP1BTERF2IPTelomeric repeat-binding factor 2-interacting protein 1

Modulation of GTP/GDP exchange via GEFs/GAPs, inhibition of post-translational geranylgeranylation, or activation through EPAC-mediated signaling pathways [PubMed 11884415, 22532568].