Gene regulation and cell fate decision in C. elegans
Head of the group
Cell fate decisions are fundamental during the development of multicellular organisms. While a few decisions seem to be reversible most differentiated cells are refractory to induced cell fate switches, unless pluripotency-inducing procedures are first applied. We aim to identify genes and epigenetic mechanisms that regulate reprogramming and direct cell fate conversions using C .elegans as a model organism. High-throughput forward genetic screens as well as RNAi knock-downs can be easily applied to C. elegans. Using these approaches, we previously identified the chromatin factor lin-53 as an inhibitor of directly converting germ cells into specific glutamatergic neuron types. Furthermore, using chromatin immunoprecipitation (ChIP) with massive parallel DNA sequencing (ChIP-Seq) and cell-specific protein purification procedures we will focus on elucidating molecular mechanisms of epigenetic regulation that control cell fate decisions and switches.
Ongoing Projects:
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Characterization of lin-53, the C. elegans ortholog of the mammalian Rbbp4/7 (formerly RbAp46/48): establishing an in vivo cell-specific protein purification method to examine the function of lin-53 in different tissues using ChIP-Seq and protein mass spectrometry.
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Forward genetic and RNAi screens to identify genes that regulate reprogramming of cell fates.
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Elucidating molecular mechanisms of the changes in chromatin modifications and structure during cell fate specification and conversion.
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Overview of the protein tagging technique using genomic fragments for cell-specific protein biochemistry. The gene of interest is tagged by fosmid recombineering. The Tag is composed of triple HA (10 aa) epitopes and double Biotin Ligase Recognition Peptide (BLRP, 16 aa) separated by TEV cleavage sites. Animals expressing the BLRP-tagged protein are crossed with transgenic animals expressing the C. elegans optimized bacterial biotin ligase BirAo. The BLRP of the target protein is only in those cells biotinylated, which express BirAo. Biotinylated proteins are efficiently purified using streptavidin-coated magnetic beads. The TEV cleavage sites allow specifically the release of the substrate protein form the beads upon treatment with TEV protease. |