This domain is the N-terminal ubiquitin-like structural domain of the FERM domain.

1: The FERM domain: a unique module involved in the linkage of cytoplasmic proteins to the membrane. Chishti AH, Kim AC, Marfatia SM, Lutchman M, Hanspal M, Jindal H, Liu SC, Low PS, Rouleau GA, Mohandas N, Chasis JA, Conboy JG, Gascard P, Takakuwa Y, Huang SC, Benz EJ Jr, Bretscher A, Fehon RG, Gusella JF, Ramesh V, Solomon F, Marchesi VT, Tsukita S, Ts Trends Biochem Sci 1998;23:281-282. PMID:9757824

2: The N-termini of FAK and JAKs contain divergent band 4.1 domains. Girault JA, Labesse G, Mornon JP, Callebaut I; Trends Biochem Sci 1999;24:54-57. PMID:10098398