FERM_f0 forms a stable globular structure. The fold is an ubiquitin-like fold joined to the f1 domain in a novel fixed orientation by an extensive charged interface. It is required for maximal integrin-activation, by interacting with other FA components, No binding partner has yet been found for it [1].

1: Structure of a double ubiquitin-like domain in the talin head: a role in integrin activation. Goult BT, Bouaouina M, Elliott PR, Bate N, Patel B, Gingras AR, Grossmann JG, Roberts GC, Calderwood DA, Critchley DR, Barsukov IL; EMBO J. 2010;29:1069-1080. PMID:20150896