Proteins are the workhorses of the cell and, over billions of years, they have evolved an amazing plethora of extremely diverse and versatile structures with equally diverse functions. Therefore, their evolution echoes the evolution of all forms of life. Evolutionary emergence of new proteins and transitions between existing ones are widely believed to be rare or even impossible.
However, recent advances in comparative genomics have repeatedly called some 10%-30% of all genes without any detectable similarity to existing proteins. Even after careful scrutiny, some of those “orphan” genes contain protein coding reading frames with detectable transcription and translation. Thus some proteins seem to have emerged from previously non-coding ‘dark genomic matter’. These ‘de novo’ proteins tend to be disordered, fast evolving, weakly expressed but also rapidly assuming novel and physiologically important functions. I will review mechanisms by which ‘de novo’ proteins might be created, under which circumstances they may become fixed and why they are elusive.
I will present a couple of studies which mostly focus on metazoan genomes.
Bâtiment: Francois Jacob -BIME
Adresse: Institut Pasteur, Paris, France