Formin protein family (FMN)

The Formin protein family consists of 15 members in humans that serve as critical regulators of the actin and microtubule cytoskeleton [1, 8]. These proteins are characterized by the presence of Formin Homology (FH) domains, specifically the FH2 domain, which facilitates the nucleation and processive elongation of linear actin filaments [1, 13]. Formins act as downstream effectors of Rho-family GTPases, integrating cellular signals to coordinate processes such as cytokinesis, cell migration, and intracellular trafficking [1, 15]. In clinical contexts, formins are significant targets in oncology, as their dysregulation is linked to tumor invasion and metastasis [3, 6]. Additionally, mutations in specific formins are associated with hereditary disorders like sensorineural hearing loss (DIAPH1) and focal segmental glomerulosclerosis (INF2) [8]. While no formin-targeted drugs are currently FDA-approved, small-molecule inhibitors like SMIFH2 and agonists like intramimics are actively being explored in preclinical research for their therapeutic potential [6, 13, 27]. However, the development of clinical agents is challenged by the functional redundancy of formin isoforms and potential off-target effects on the myosin superfamily [9, 26].

Other names

Formin homology proteinsFH2 domain-containing proteinsDiaphanous-related forminsDrfs

Inhibition of the FH2 domain to block actin nucleation and elongation, or activation of formins to stabilize the cytoskeleton and induce cell cycle arrest.