High-density CRISPRi screens reveal adaptive transcriptional gradients in cyanobacteria

ABSTRACT: Cyanobacteria are the oldest form of photosynthetic life and contribute to primary production in nearly every habitat, from permafrost to hot springs. Despite longstanding interest in the biochemical basis of environmental adaptation in these microbes, it remains poorly understood. Here we used a high-density, genome-wide CRISPRi screen to examine the influence of gene-specific transcriptional variation on the growth of Synechococcus sp. PCC 7002 under environmental extrema. Surprisingly, many partial knockdowns enhanced fitness under cold monochromatic conditions. Notably, transcriptional repression of a gene for a core subunit of the NDH-1 complex, which is important for photosynthesis and carbon uptake, improved growth rates under both red and blue light but at distinct, color-specific optima. Multi-target transcriptional repression produced nonadditive effects. Findings reveal diverse mechanisms of environmental adaptation in cyanobacteria and provide a new approach for using gradients in sgRNA activity to pinpoint biochemically influential transcriptional changes in cells.

INSTRUMENT(S): Q Exactive Plus

ORGANISM(S): Synechococcus Sp. Pcc 7002 (ncbitaxon:32049)

SUBMITTER: Paul Abraham  

PROVIDER: MSV000094564 | MassIVE | Thu Apr 18 08:01:00 BST 2024

SECONDARY ACCESSION(S): PXD051561

REPOSITORIES: MassIVE