Molecular cloning and distinct developmental expression pattern of spliced forms of a novel zinc finger gene wiz in the mouse cerebellum.
In the course of a study conducted to identify the mouse homologue of Drosophila eyes absent (eya), we isolated a novel mouse cDNA fragment which show little homology to eya but encodes a protein with Krüppel (C2H2)-type zinc finger motifs. By further screening using this cDNA fragment as a probe, we obtained the short and long forms of full-length cDNAs, which were apparently alternatively spliced products from one gene. Since both mRNAs encode proteins with widely-interspaced zinc finger motifs, we termed this gene wiz and refer to the short and long wiz transcripts as wizS and wizL, respectively. In situ hybridization studies using the probe against the region common to wizS and wizL showed that these mRNAs were expressed abundantly in the granule cell layers of the mouse cerebellum, the olfactory bulb, and the dentate gyrus, whereas the same technique using the probe against only wizL could not detect positive signals in the developing cerebellum, indicating that there is no expression of wizL mRNA there. Northern blot and in situ hybridization analyses demonstrated that the extracerebellar regions expressed both wizS and wizL mRNAs from the midgestational period to adulthood. The finding that two types of wiz transcripts (wizS and wizL) are expressed with different developmental patterns might indicate separate transcription functions in the cerebellar granule cells and the extracerebellar regions.