High- density CRISPRi screens reveal diverse routes to improved acclimation in cyanobacteria

• 成果类型: Article
• 署名作者: Hren, Andrew; Lollini, Nicole; Carper, Dana L.; Abraham, Paul E.; Cameron, Jeffrey C.; Fox, Jerome M.; Eckert, Carrie A.
• 署名单位: University of Colorado System; University of Colorado Boulder; United States Department of Energy (DOE); Oak Ridge National Laboratory; University of Colorado System; University of Colorado Boulder; University of Colorado System; University of Colorado Boulder; United States Department of Energy (DOE); National Renewable Energy Laboratory - USA
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-11753
• DOI: 10.1073/pnas.2412625122
• 发表日期: 2025-03-25
• 关键词: state transitions; light; adaptation

摘要

Cyanobacteria are the oldest form of photosynthetic life on Earth and contribute to primary production in nearly every habitat, from permafrost to hot springs. Despite longstanding interest in the acclimation of these microbes, it remains poorly understood and challenging to rewire. This study uses a high- density, genome- wide CRISPR interference screen to examine the influence of gene- specific transcriptional variation on the growth of Synechococcus sp. PCC 7002 under environmental extremes. Surprisingly, many partial knockdowns enhanced fitness under cold monochromatic conditions. Transcriptional repression of genes for core subunits of the NDH- 1 complex, which are important for photosynthesis and carbon uptake, improved growth rates under both red and blue light but at distinct, color- specific optima. Most genes with fitness- improving knockdowns were distinct to each light color, and dual- target transcriptional repression produced nonadditive effects. Findings reveal diverse routes to improved acclimation in cyanobacteria (e.g., attenuation of genes involved in CO2 uptake, light harvesting, translation, and purine metabolism) and provide an approach for using gradients in sgRNA activity to pinpoint biochemically influential transcriptional changes in cells.