TY - JOUR TI - Complex chromosomal neighborhood effects determine the adaptive potential of a gene under selection AU - Steinrueck, Magdalena AU - Guet, Călin C A2 - Laub, Michael T VL - 6 PY - 2017 DA - 2017/07/25 SP - e25100 C1 - eLife 2017;6:e25100 DO - 10.7554/eLife.25100 UR - https://doi.org/10.7554/eLife.25100 AB - How the organization of genes on a chromosome shapes adaptation is essential for understanding evolutionary paths. Here, we investigate how adaptation to rapidly increasing levels of antibiotic depends on the chromosomal neighborhood of a drug-resistance gene inserted at different positions of the Escherichia coli chromosome. Using a dual-fluorescence reporter that allows us to distinguish gene amplifications from other up-mutations, we track in real-time adaptive changes in expression of the drug-resistance gene. We find that the relative contribution of several mutation types differs systematically between loci due to properties of neighboring genes: essentiality, expression, orientation, termination, and presence of duplicates. These properties determine rate and fitness effects of gene amplification, deletions, and mutations compromising transcriptional termination. Thus, the adaptive potential of a gene under selection is a system-property with a complex genetic basis that is specific for each chromosomal locus, and it can be inferred from detailed functional and genomic data. KW - bacterial genetics KW - regulatory evolution KW - experimental evolution KW - adaptation KW - gene expression KW - chromosomal architecture JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -