Meeting Abstract
P2.39 Monday, Jan. 5 The Evolutionary Diversification of LSF and Grainyhead Transcription Factors Preceded the Cnidarian-Bilaterian Split TRAYLOR-KNOWLES, Nikki G.*; HANSEN, Ulla; KAUFMAN, Les; FINNERTY, John R.; Boston University; Boston University; Boston University; Boston University ntk17@bu.edu
The LSF/Grainy head (GRH) transcription factors are critical during both development and homeostasis, being involved in regulation of cell cycle, cell division, and cellular differentiation in a range of developmental and non-developmental contexts. The LSF/GRH family is split into the LSF/CP2 subfamily and the GRH subfamily, which can be distinguished by their distinctive oligomerization domains and differences in their oligomerization behavior. In order to understand the functional evolution of LSF and GRH, it is necessary to identify the ancestor in which the original gene duplication occurred. This will allow us to reconstruct the functional repertoire of the LSF/GRH ancestor, and to compare this inferred ancestral condition with the function of LSF and GRH in a phylogenetic progression of extant taxa. By doing a bioinformatic query of newly available genomes, including Monosiga brevicollis, Trichoplax adhaerens, Amphimedon queenslandica, Volvox carteri and several fungi, we have found that the origin of a distinct LSF and GRH subfamilies predated the diversification of triploblasts into distinct protostome and deuterostomes lineages and appears to have ancestral proteins present in algae and fungia much more distant evolutionary past then previously thought. We report the identification of LSF/GRH family members in 23 species, including basal metazoans, fungi, and algae. MEME analysis was used to identify conserved protein domains within LSF/GRH family. Interestingly, Nematostella vectensis seems to display two potential loci for GRH-like genes, and most surprisingly Volvox carteri has shared conservation of the DNA binding domain of this family, indicating that this gene is truly an ancestral gene of metazoan LSF/GRH family.
