Project

Evolution and diversification of Argonaute proteins

Argonaute (Ago) proteins are present in both eukaryotes and prokaryotes. In eukaryotes like humans, Agos control gene expression after transcription (RNA silencing), while in prokaryotes, they defend against cellular invaders. Considering that eukaryotes evolved from the fusion of two prokaryotic cells (bacterium and archaeal cell), we hypothesize that some prokaryotic Agos might also perform RNA silencing, akin to eukaryotic Agos. This project studies the biochemical function of Ago proteins in Asgard archaea, the closest prokaryotic relative to eukaryotes.

Background

The best-studied Argonaute (Ago) proteins are those found in eukaryotes, which regulate gene expression post-transcriptionally by using small RNA molecules to target and degrade complementary RNA. In contrast, prokaryotic Agos confer immunity to the cell by directly interfering with bacteriophage, plasmid, and transposon DNA. Although the defensive function orchestrated by Ago proteins is conserved across domains, the ability to regulate gene expression post-transcription is hitherto only described for eukaryotes, as is the mechanism of RNA-guided RNA targeting. Consequently, the origin of the eukaryotic RNA silencing machinery remains unknown.

Aim of the project

A recently characterised prokaryotic Ago from Asgard archaea exhibits RNA silencing activity in vivo, and can use RNA guides to cleave RNA targets in vitro [1]. Based on the close phylogenetic proximity of Asgard archaea to eukaryotes, we hypothesize that other Asgard archaeal Agos can also facilitate RNA silencing, akin to eukaryotic Agos. This project aims to characterize the function, mechanism and structure of Asgard archaeal Agos.

Join the project for a bachelor or master thesis

As a thesis student you will:

  • Learn various biochemical, microbial, and biophysical techniques
  • Perform both in vitro and in vivo experiments
  • Perform molecular cloning and express and purify proteins

Contact

Do you have a question about argonautes, or would you like to join us as a student researcher? Please contact us.

Publications