My interest is to understand one of the most important evolutionary transitions in life's history: the emergence of multicellular organisms from their unicellular ancestors. Multicellularity has evolved several times independently within the tree of life, such in algae, plants, fungi and animals or metazoans. In this project, done at Andrew Roger's lab at Dalhousie University, we focused on multicellularity origins within animals or Metazoa.
The first step in order to infer significant insights into this question is to have a well-resolved phylogenetic tree of the origin of animals. The second one is to obtain genomic information from the unicellular lineages most closely related to animals. With this aim we performed EST projects from both Capsaspora owczarzaki and Sphaeroforma arctica, recently shown to be closely related to animals. With our data we have largely increase the genomic information on those single-celled lineages. By constructing large concatenated amino acid alignments, we have been able to improved the phylogenetic framework on the origin of Metazoa. Interestingly, we have identified in those organisms some proteins involved in multicellularity previously though to be animal-specific. The information from this project will provide important insights into how multicellularity arose within animals and into the evolutionary origin of gene families that are key for animal development.
