Punctuated evolution and transitional hybrid network in an ancestral cell cycle of fungi

• DOI: 10.7554/elife.09492
• Publication Date: 2016-04-29T10:10:36Z
• Authors: Edgar M Medina; Jonathan J Turner; Raluca Gordân; Jan M Skotheim; Nicolas E Buchler
• Keywords: E2F; Lineage (genetic)

Although cell cycle control is an ancient, conserved, and essential process, some core animal fungal regulators share no more sequence identity than non-homologous proteins. Here, we show that evolution along the lineage was punctuated by early acquisition entrainment of SBF transcription factor through horizontal gene transfer. Cell in ancestor then proceeded a hybrid network containing both its ancestral counterpart E2F, which still maintained many basal fungi. We hypothesize virally-derived may have initially hijacked activating via cis-regulatory elements targeted regulator much like extant viral oncogenes. Consistent with this hypothesis, can regulate promoters E2F binding sites budding yeast.