Course Coordinators: K. Stathopoulos, K. Nika

The aim of this course is to provide a critical understanding of the flow of genetic information and the cellular process of its decoding into protein. In the context of the course, postgraduate students are encouraged to gain an in-depth understanding of the biochemical processes involved in transcription, post-transcriptional processing of RNA and its translation into protein. The course also aims at understanding the structure and function of the ribosome, which is the most complex ribonucleo-protein complex, and also the main target of most of the prescribed antibiotics. The mechanisms of resistance of microorganisms to these antibiotics and the potential-actions to treat multi-resistant microorganisms are also described. Finally, the mechanisms of viral replication in host cells and their application to mRNA vaccines are described.

Educational Objectives

The main educational objective of the course is the in-depth understanding by graduate students of the biochemical processes involved in the biosynthesis of RNA molecules (coding and non-coding) and in the process of translation of information encoded by mRNA in physiological and pathological situations. Emphasis is given to the structure and function of important ribonucleoprotein complexes of both the transcriptional (RNA polymerases) and translational machinery (ribosome, splicesome). In addition, the aim is to understand the biosynthesis of numerous non-coding RNAs and their role in modern molecular diagnostics and specialized therapy.

Course Content

Transcription

• The RNA-world hypothesis
• RNA synthesis: transcription factors and initiation of RNA synthesis, elongation of the RNA chain, termination of RNA synthesis
• Post-transcriptional processing of RNA: post-transcriptional processing of mRNA, post-transcriptional processing of rRNA, post-transcriptional processing of tRNA, self-splicing, splicesomes
• Ribozymes: group I and group II introns, hammerhead ribozymes, ribonuclease P, role of ribozymes in gene therapy
• RNA interference and regulation of gene expression
• Noncoding RNAs, molecular diagnostics and new RNA therapies
• RNA-mediated regulation in prokaryotic and eukaryotic organisms

Translation

• Origin and evolution of ribosomal tRNA and aminoacyl-tRNA synthetases: structure and function of tRNA, activation of amino acids
• Ribosome structure and function: isolation techniques of ribosomal proteins and rRNA, structure of ribosomal proteins and rRNA, effect of ions and organic compounds on the structure of rRNA and ribosomal proteins, study of ribosome structure and function using mutations, topography of the ribosome
• Regulation of ribosome biosynthesis
• Mechanism of protein synthesis: initiation: recognition of mRNA by ribosomes, binding of the insertion of αa-tRNA into the ribosome and molecular basis of the function of initiation factors, elongation, termination
• Deregulation of protein synthesis in pathological conditions
• Accuracy of translation
• The use of antibiotics as tools to study ribosome function
• Post-translational processing of the newly synthesized polypeptide chain: Chemical modifications, Molecular chaperones and their role in obtaining the tertiary conformation of the polypeptide chain
• Degradation and recycling of mRNA – the role of nucleases