| Title: | Stochasticity in the enterococcal sex pheromone response revealed by quantitative analysis of transcription in single cells |
| Author(s): | Breuer RJ; Bandyopadhyay A; O'Brien SA; Barnes AMT; Hunter RC; Hu WS; Dunny GM; |
| Address: | "Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, United States of America. Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota, United States of America. Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, Minnesota, United States of America" |
| DOI: | 10.1371/journal.pgen.1006878 |
| ISSN/ISBN: | 1553-7404 (Electronic) 1553-7390 (Print) 1553-7390 (Linking) |
| Abstract: | "In Enterococcus faecalis, sex pheromone-mediated transfer of antibiotic resistance plasmids can occur under unfavorable conditions, for example, when inducing pheromone concentrations are low and inhibiting pheromone concentrations are high. To better understand this paradox, we adapted fluorescence in situ hybridization chain reaction (HCR) methodology for simultaneous quantification of multiple E. faecalis transcripts at the single cell level. We present direct evidence for variability in the minimum period, maximum response level, and duration of response of individual cells to a specific inducing condition. Tracking of induction patterns of single cells temporally using a fluorescent reporter supported HCR findings. It also revealed subpopulations of rapid responders, even under low inducing pheromone concentrations where the overall response of the entire population was slow. The strong, rapid induction of small numbers of cells in cultures exposed to low pheromone concentrations is in agreement with predictions of a stochastic model of the enterococcal pheromone response. The previously documented complex regulatory circuitry controlling the pheromone response likely contributes to stochastic variation in this system. In addition to increasing our basic understanding of the biology of a horizontal gene transfer system regulated by cell-cell signaling, demonstration of the stochastic nature of the pheromone response also impacts any future efforts to develop therapeutic agents targeting the system. Quantitative single cell analysis using HCR also has great potential to elucidate important bacterial regulatory mechanisms not previously amenable to study at the single cell level, and to accelerate the pace of functional genomic studies" |
| Keywords: | "Drug Resistance, Bacterial/genetics Enterococcus faecalis/drug effects/*genetics *Gene Transfer, Horizontal Genome, Bacterial Humans In Situ Hybridization, Fluorescence Pheromones/*genetics Plasmids/genetics Sex Attractants/*genetics Single-Cell Analysis;" |
| Notes: | "MedlineBreuer, Rebecca J Bandyopadhyay, Arpan O'Brien, Sofie A Barnes, Aaron M T Hunter, Ryan C Hu, Wei-Shou Dunny, Gary M eng R35 GM118079/GM/NIGMS NIH HHS/ T32 GM008347/GM/NIGMS NIH HHS/ R01 GM081388/GM/NIGMS NIH HHS/ R01 GM049530/GM/NIGMS NIH HHS/ T32 HL007741/HL/NHLBI NIH HHS/ 2017/07/04 PLoS Genet. 2017 Jul 3; 13(7):e1006878. doi: 10.1371/journal.pgen.1006878. eCollection 2017 Jul" |
