Detection of Embryonic Gene Expression Dynamics

by Thomas Bürglin (Department of Biosciences and Nutrition, KI)

Wednesday 19 Nov 2008, 16:00 → 17:00 Europe/Stockholm

RB35 (RB35)

Gene expression is extensively studied in C. elegans at different levels. While protein and RNA detection methods reveal localization and changes in expression on a rather rough temporal scale, fluorescent reporter transgenes allow expression studies in vivo. Even though those reporters are unable to represent the final protein expression they give detailed information suitable to construct models of regulatory networks. In addition to the recently published genome wide promoterome screens (Hunt-Newbury et al., 2007; Dupuy et al., 2007; Reece-Hoyes et al., 2007) we propose a system to automatically obtain, map and compare embryonic promoterome data. In addition to the localization we emphasize on the detection and quantification of rapid changes in transcription during cell differentiation. We have focused on genes known or expected to be expressed during embryogenesis such as homeodomain containing transcription factors. We find that several homeobox genes show highly dynamic expression patterns that are easily overlooked using established methods. We have screened over 80 genes in over 200 individual transgenic animals. The expression patterns are normalized to a standard spatiotemporal (4D) coordinate system and can be compared. The temporal expression patterns obtained from different transgenic reporter individuals for a particular promoter usually correlate with r > 0.98. The success rate with our system to obtain a complete 4D expression pattern from a single transgenic embryo is greater than 95%. In conclusion, we have developed a generally applicable method and workflow for obtaining high-resolution 4D transcriptome and proteome data.