Zic1 is a C2H2 zinc finger transcription factor that controls the expansion of neuronal precursors by inhibiting the progression of neuronal differentiation. Zic1 determines the cerebellar folial pattern by influencing proliferation in the external germinal layer (EGL). Zic1 can bind and transactivate the apolipoprotein E gene.This gene is closely linked to the gene encoding zinc finger protein of the cerebellum 4, a related family member on chromosome 3.