Core Fermentation (CoFe) granules focus coordinated glycolytic mRNA localization and translation to fuel glucose fermentation

Fabian Morales-Polanco,Christian Bates,Jennifer Lui,Joseph Casson,Clara A Solari,Mariavittoria Pizzinga,Gabriela Forte,Claire Griffin,Kirsten E.L Garner,Harriet E Burt,Hannah L Dixon,Simon Hubbard,Paula Portela,Mark P Ashe

doi:10.1016/j.isci.2021.102069

Abstract

SummaryGlycolysis is a fundamental metabolic pathway for glucose catabolism across biology, and glycolytic enzymes are among the most abundant proteins in cells. Their expression at such levels provides a particular challenge. Here we demonstrate that the glycolytic mRNAs are localized to granules in yeast and human cells. Detailed live cell and smFISH studies in yeast show that the mRNAs are actively translated in granules, and this translation appears critical for the localization. Furthermore, this arrangement is likely to facilitate the higher level organization and control of the glycolytic pathway. Indeed, the degree of fermentation required by cells is intrinsically connected to the extent of mRNA localization to granules. On this basis, we term these granules, core fermentation (CoFe) granules; they appear to represent translation factories, allowing high-level coordinated enzyme synthesis for a critical metabolic pathway.

Highlights

The glycolytic pathway lies at the core of metabolic activity as a virtually ubiquitous biochemical pathway across living cells
Glycolytic mRNAs localize to granules under active growth conditions Previous work from our laboratory has highlighted that the glycolytic mRNAs, PDC1 and ENO2, encoding pyruvate decarboxylase and enolase, respectively, are translated in cytoplasmic granules (Lui et al, 2014) (Figure 1A)
To evaluate whether glycolytic mRNAs in general are localized to these sites, we have utilized the m-TAG system, where elements of the MS2 bacteriophage are used to tether GFP to an mRNA to study its localization in live cells (Haim-Vilmovsky et al, 2011)

Summary

Introduction

The glycolytic pathway lies at the core of metabolic activity as a virtually ubiquitous biochemical pathway across living cells. The impact of the stem loop on PDC1 mRNA levels is not as pronounced as the STOP codon insertion, and it is a little surprising that this insertion leads to mRNA destabilization, as this same stem loop has been inserted into a number of mRNAs without impacting upon overall mRNA levels (Palam et al, 2011; Pizzinga et al, 2019; Vattem and Wek, 2004) This suggests that the context of a stem loop in the 5’UTR of an mRNA is important in determining to what extent the insertion impacts upon the fate of the mRNA. These results highlight the intimate connection between the translation of an mRNA and its stability and add to many observations showing that a reduction in translation can lead to mRNA destabilization (Roy and Jacobson, 2013)

Methods

Results

Discussion

Conclusion