Finding FISH in a small pond

Abstract

Advanced microscopy and labeling techniques reveal that bacteria localize mRNAs within their cells in a similar way to eukaryotes.

Keywords: E. coli; RNA degradation; biophysics; cell biology; fluorescence in situ hybridization; next-generation sequencing; spatial organization; structural biology; superresolution microscopy; transcriptome.

Figure 1.. The distribution of mRNAs in E. coli reflects how newly built proteins are processed.

Genetic instructions encoded in the DNA of the chromosome are copied, or transcribed, by enzymes called RNA polymerases (purple) into mRNAs (thin lines). These mRNA are then translated into proteins by ribosomes (depicted in gray). Moffitt et al. show that mRNAs that encode soluble proteins (orange) diffuse freely from the chromosome and are translated throughout the cytosol. Similarly, mRNAs that encode proteins that will be release into the periplasm or beyond (blue) are found throughout the cytosol. Membrane proteins (green) are insoluble in the cytosol and are instead translated at the inner membrane. The degradasome (yellow) is also found at the inner membrane and preferentially breaks down nearby mRNAs.