LIM domain proteins

LIM domain proteins are implicated in fundamental developmental processes, and the functional hallmark of all LIM domains is presumably the mediation of protein–protein interactions. Although originally identified in LIM-homeodomain proteins, LIM domains have now been identified in a variety of proteins that lack homeodomains, either being entirely composed of LIM domains or containing additional functional domains of various types (e.g. kinase domains). The LIM domain contains a distinct cysteine-rich motif that was first identified in the protein products of three genes – lin-1, isl1, and mec-3. The LIM motif is composed of two zinc finger structures separated by a two-amino acid spacer and comprises the conserved sequence CX2CX16 − 23HX2CX2CX2CX16 − 21CX2(C/H/D). 3D Structure Keywords: protein–protein interaction module; multidomain protein; cell differentiation; transcription factor activation; zinc finger; NMR spectroscopy