Understanding the molecular principles governing mRNP architecture

Introduction

Eukaryotic messenger ribonucleoprotein (mRNP) particles are the functional entities that carry genetic information to the protein synthesizing machinery. These ribonucleoprotein complexes are dynamic and diverse, as highlighted by the copious number of proteins and transcripts identified in global proteomic and transcriptomic studies.

Knowledge Gap

However, little is known about the composition and architecture of individual mRNPs, and how changes in mRNP structure relate to their function or to dysfunction. The GOVERNA project will address this gap in knowledge by purifying specific mRNPs and delving into their molecular and structural arrangement.

Methodology

With our preliminary data serving as a springboard, the project combines:

1. Genomic tagging engineered to maintain the most physiologically relevant conditions.
2. Biochemical methods developed to preserve the integrity of transient ribonucleoprotein assemblies.
3. Mass spectrometry and cryo-electron microscopy to identify the composition and architecture of mRNPs.

Research Focus

We will zoom in on a set of paradigms in RNA biology that not only sample the breadth of mRNP diversity but are also powerful model systems for linking structural information and biological function.

Specific Investigations

We will investigate the molecular features in the three-dimensional organization of:

• Nuclear mRNPs from S. cerevisiae.
• Translationally repressed mRNPs in early developmental stages in D. melanogaster and X. laevis.

For mRNPs undergoing active translation, we will investigate the transitions of human beta-globin mRNPs in the course of a surveillance process connected to disease.

Expected Outcomes

By studying these examples, we will glean fundamental insights into global principles governing the packaging of mRNPs and the remodeling of their three-dimensional features throughout a transcript's life cycle. The cumulative output will illuminate a central node of eukaryotic gene expression that is also particularly timely and relevant given recent developments in mRNA-based therapeutics.