biostudies-literatureUnknownWinkelman JTBacteria employ sophisticated post-transcriptional regulatory mechanisms to adapt to environmental changes. Carbon storage regulator A (CsrA), a highly conserved small RNA-binding protein, serves as a critical post-transcriptional regulator by recognizing GGA motifs in target transcripts and typically repressing translation. Despite extensive research, how this conserved regulator has evolved diverse species-specific regulatory networks remains unclear. Here, using <i>Bacillus subtilis</i> as an experimental chassis, we have developed Swarm-seq - a high-throughput functional genomics platform capable of assessing CsrA homologs across the Bacterial domain for their ability to regulate flagella-dependent swarming motility. Systematically testing over five-hundred codon-optimized <i>csrA</i> bioRxiv : the preprint server for biology2025.05.05.652322https://www.ebi.ac.uk/biostudies/studies/S-EPMC12247646biostudies-literatureSwarm-seq Reveals Functional Divergence in CsrA Homologs Across Bacteria.PMC12247646Winkelman JTWinkelman JDYarberry EMukherjee SfalseSwarm-seq Reveals Functional Divergence in CsrA Homologs Across Bacteria.Bacteria employ sophisticated post-transcriptional regulatory mechanisms to adapt to environmental changes. Carbon storage regulator A (CsrA), a highly conserved small RNA-binding protein, serves as a critical post-transcriptional regulator by recognizing GGA motifs in target transcripts and typically repressing translation. Despite extensive research, how this conserved regulator has evolved diverse species-specific regulatory networks remains unclear. Here, using <i>Bacillus subtilis</i> as an experimental chassis, we have developed Swarm-seq - a high-throughput functional genomics platform capable of assessing CsrA homologs across the Bacterial domain for their ability to regulate flagella-dependent swarming motility. Systematically testing over five-hundred codon-optimized <i>csrA</i> 2025-01-01T00:00:00Z2025 May2025-08-28T03:09:23.45Z2025-08-28T03:09:23.45ZS-EPMC122476464065483210.1101/2025.05.05.652322