Microphthalmia associated transcription factor (MITF) is a basic helix-loop-helix-leucine zipper transcription factor essential for the development of melanocytes. RNA in-situ hybridization data shows clear expression of Mitf in the mouse olfactory bulb and possibly also in the cerebellum and hippocampus. So far we have determined that expression of Mitf is absent from the Mitf mutant mouse olfactory bulb. A global gene expression study, comparing the Mitf mutant and heterozygote mice, shows a number of genes downregulated in the mutant olfactory bulb. Many of these have known MITF binding sites in their promoter and are thus candidates for being Mitf target genes in neurons. This is further supported by antibody staining, which shows MITF in a subset of OB neurons.  There are 7 known isoforms of MITF - whether they or novel isoforms are present in the CNS is also under study as well as the role of MITF in neuronal morphology.