Christa S. Merzdorf
Assistant Professor of Developmental NeurobiologyDepartment of Cell Biology and Neuroscience,
Montana State University
We study molecular mechanisms that underlie patterning of the vertebrate nervous system during embryonic development. The foundation of nervous system development is laid during gastrula stages and continues during neurula stages. During this process, part of the embryonic ectoderm (the neurectoderm) is induced and subsequently patterned to form the nervous system. Many regulatory genes are involved in this patterning process, which ultimately allows region-specific differentiation of the neurectoderm into the correct parts of the nervous system. Early players in neural patterning include the genes of the zic family. One major focus of our work is to understand the roles that the transcription factor zic1 plays during early neural development, using Xenopus and chick embryos as model systems. Developmental genes often play multiple parts throughout development. Similarly, zic1 is involved not only in early patterning of the neural plate, but also in other developmental processes that include induction of the neural crest, formation of the midbrain/hindbrain boundary, in addition to roles in cerebellum, eye, somite, and limb bud development. In order to understand the activities of the zic1 gene at the molecular level, it is of great interest to identify genes that are regulated by this transcription factor. Thus, we have conducted a microarray screen in Xenopus, designed to identify genes that are direct targets of zic1. One of these genes is the novel gene, Xfeb, that may act as a protease and participates in patterning of the hindbrain. Several other genes that we identified, participate in early neural crest formation. Many additional genes from our screen await further study, including genes that point to interesting, previously unknown, activities, in which zic genes may engage.