Fibroblast growth factor homologous factors (FHFs) are a noncanonical subset of intracellular fibroblast growth factors that have been implicated in a variety of neurobiological processes and in disease. They are most prominently regulators of voltage-gated Na+ channels (NaVs). In this review, we discuss new insights into how FHFs modulate NaVs. This is followed by a summary of a growing body of evidence that FHFs operate in much broader fashion. Finally, we highlight unknown aspects of FHF function as areas of future interest.
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