We all start out as a single fertilized cell. This cell subsequently divides, giving rise to hundred of distinct cell types. We receive half our genetic information from one parent, and the other half from our other parent. Together, both sets of genetic information (or DNA or chromosomes) comprise our genome. This means that (with a few key exceptions) all cells in an organism contain identical genomes. How then does cell-type variation arise?
The answer is that different cell types express different combinations of genes. Metazoan diversity, both at the cellular and organismal level, is largely controlled by gene regulatory networks that create spatial and temporal patterns of gene expression. At the transcriptional level, most network interactions represent direct binding events between transcription factors and specific DNA sequences (enhancers) in target genes. Individual transcription factors play multiple roles during development, controlling distinct subsets of target genes in specific contexts. Additionally, proteins with very similar binding affinities can exist within the same cell and it is unclear how binding events are coordinated so that each protein activates its own specific gene targets. Major questions remain concerning which sequences are available for binding in a specific cell and how individual binding events are coordinated so that the correct batteries of target genes are expressed in each cell type at the appropriate time in development. The research in our lab serves to understand the mechanisms that control the spatiotemporal dynamics of gene expression, especially in terms of protein structure, binding specificity, binding site number, and combinatorial activation by cofactors.
We conduct research in the fruit fly, Drosophila melanogaster. Drosophila melanogaster is a singularly powerful system for studying transcriptional events. Specifically, the analysis of single copy transgenes in the same genomic position, visual assays of protein and RNA patterns, BAC recombineering, CRISPR-CAS, mutability, and experimental turnaround make this insect a powerhouse of molecular research.
The answer is that different cell types express different combinations of genes. Metazoan diversity, both at the cellular and organismal level, is largely controlled by gene regulatory networks that create spatial and temporal patterns of gene expression. At the transcriptional level, most network interactions represent direct binding events between transcription factors and specific DNA sequences (enhancers) in target genes. Individual transcription factors play multiple roles during development, controlling distinct subsets of target genes in specific contexts. Additionally, proteins with very similar binding affinities can exist within the same cell and it is unclear how binding events are coordinated so that each protein activates its own specific gene targets. Major questions remain concerning which sequences are available for binding in a specific cell and how individual binding events are coordinated so that the correct batteries of target genes are expressed in each cell type at the appropriate time in development. The research in our lab serves to understand the mechanisms that control the spatiotemporal dynamics of gene expression, especially in terms of protein structure, binding specificity, binding site number, and combinatorial activation by cofactors.
We conduct research in the fruit fly, Drosophila melanogaster. Drosophila melanogaster is a singularly powerful system for studying transcriptional events. Specifically, the analysis of single copy transgenes in the same genomic position, visual assays of protein and RNA patterns, BAC recombineering, CRISPR-CAS, mutability, and experimental turnaround make this insect a powerhouse of molecular research.
Nuclei in the early Drosophila embryo.