Human FGF-12 Alexa Fluor™ Plus 488-conjugated Antibody

Fibroblast growth factor 12 (FGF-12) is a member of the FGF superfamily of molecules which contains at least 22 members. The FGFs are characterized by the presence of a core, 120 amino acid (aa) beta-trefoil structure, and all apparently bind heparin (1, 2). FGF-11, -12, -13, -14, originally termed FGF homologous factors (FHF) -3, -1, -2, -4, respectively, form a subgroup within the FGF family (1, 3). Human FGF-12/FHF-1 is synthesized as a 243 aa protein. It lacks a typical signal sequence and is considered to be a cytoplasmic protein. It does, however, possess an N-terminal bipartite nuclear localization signal (NLS) at aa 11‑18 and 28‑38 (4‑6). The 243 aa protein has at least one alternate splice form that is 181 aa in length. This is termed FGF-12B. Alternate splicing deletes the N-terminal 66 aa in FGF‑12 and replaces them with four aa in FGF-12B. This substitution removes the NLS from the short form. Studies on the short form (12B) show that it cannot bind any of the common FGF receptors. This is consistent with its cytoplasmic localization. It can, however, bind to IB2 (islet brain-2), a cellular kinase scaffold protein, and voltage-gated sodium channels, suggesting FGF-12B plays an important role in intracellular signaling and ion exchange (7). Mouse and human FGF-12B differ by only one amino acid.