Watch the recording


This webinar will discuss how homologous recombination at the highly conserved rDNA locus in Arabidopsis thaliana is tightly regulated during meiosis, a fundamental process and key to plant breeding and food security.

The rDNA locus encodes the ribosomal RNA (rRNA) genes, which constitute the catalytic core of the ribosomes – complex and abundant molecular machines responsible for translating the genetic information from mRNAs into proteins in all living cells. By combining cytological and next generation sequencing approaches, Jason Sims and colleagues at the Max Perutz Labs found that the rDNA locus is embedded within a unique meiotic-refractory environment that is tightly controlled throughout meiotic progression.

In his presentation Dr.Sims will outline:

  • How he and his colleagues revealed the presence of tissue-specific ribosomal variants in Arabidopsis.
  • How the variants are differentially transcribed at different meiotic stages.

These findings support the concept of specialized ribosome subpopulations with distinct rRNA composition that are assembled in a tissue-specific manner and may exert regulatory functions based on their rRNA composition.

Speaker’s biography


Jason Sims, PhD
Department of Chromosome Biology
Max Perutz Labs, University of Vienna

Jason Sims obtained his PhD from the University of Vienna, working on meiosis and the stability of the rDNA locus. As a postdoc at the Max Perutz Labs, he generated the first draft assembly of the rDNA region for any organism by using Arabidopsis thaliana as a model. He also identified the presence of ribosomal variants in Arabidopsis that are tissue-specifically expressed. In October he will continue to pursue his line of research as a senior researcher at the University of Hamburg by looking at the expression of ribosomal variants in meiosis and their biological relevance.