Poster abstracts

Poster number 42 submitted by Yifei Zhang

New Insight into Prepattern Hypothesis from Study in fred Regulatory Network

Yifei Zhang (OSBP), Shweta Chandra (MCDB), Harald Vaessin (MG)

Abstract:
Peripheral sensory organs development in Drosophila has been an ideal model to study neurogenesis for many years. According to the widely accepted Prepattern Hypothesis, this process is delicately regulated by three groups of genes: prepattern genes to set up spatial and temporal coordinates, proneural genes to provide neural fate potentials, and neurogenic genes to restrict neural fate determination.
Our previous study revealed a gene friend of echinoid (fred) that plays key roles in suppressing neural fate in wing disc epidermal cells. When fred is knocked down by inducible fred-RNAi in different regions of the wing disc, ectopic sensory organ precursors (SOPs) arise from almost all cells, including outside of proneural clusters. This result suggests that neural potentials exist in of nearly all cells of the wing imaginal discs, not limited to cells within proneural clusters. We carried out a microarray study and identified 72 significantly up-regulated genes and 60 significantly down-regulated genes in fred-RNAi background. Interestingly, a prepattern gene pannier (pnr), especially one of its isoforms pnr-beta, is suppressed by fred knock-down. It is surprising because pnr is required for proneural cluster formation, and pnr-beta was proved to promote proneural gene expression. Our study has identified the outlines of the fred regulatory network required for the suppression of ectopic SOP formation in imaginal wing discs. The results of this analysis will be presented.

Keywords: SOP, fred, Prepattern Hypothesis