Zic4 Background Information Zic4 (zinc finger protein of the cerebellum 4) is a C2H2 zinc finger transcription factor that influences cerebellar development. Zic4 localizes to the nuclei of cerebellar granule cells. Zic4 mRNA expression peaks on postnatal day 5 in the developing cerebellum of mouse. Zic family members are important during development, and have been associated with X-linked visceral heterotaxy and holoprosencephaly type 5. Zic4 is closely linked to Zic1, a related family member on chromosome 3.