Learning perturbation-inducible cell states from observability analysis of transcriptome dynamics
Aqib Hasnain1, Shara Balakrishnan2, Dennis M Joshy3
1Department of Mechanical Engineering, University of California Santa Barbara, Santa Barbara, CA, USA. aqib@ucsb.edu.
Nature Communications
|May 30, 2023
Summary
Researchers developed a machine learning tool to discover gene biomarkers for detecting environmental toxins. This system identifies analyte-responsive promoters, creating a living sensor for malathion detection in real-world conditions.
Area of Science:
- Biotechnology and Synthetic Biology
- Environmental Science
- Genomics and Bioinformatics
Background:
- Identifying reliable biomarkers for specific perturbations and metabolites is a significant hurdle in biotechnology and biomanufacturing.
- Transcriptome-wide analysis of gene expression dynamics is crucial for understanding cellular responses to external stimuli.
Purpose of the Study:
- To develop a data-driven method for discovering analyte-responsive promoters using transcriptome-wide time-series RNA sequencing data.
- To create a living biosensor for detecting the organophosphate malathion in environmental samples.
- To establish a machine learning framework applicable to various host organisms for discovering perturbation-inducible gene expression systems.
Main Methods:
- A transcriptome-wide approach was employed to rank perturbation-inducible genes from time-series RNA sequencing data.
- Low-dimensional models of gene expression dynamics were constructed, and genes were ranked using observability analysis to identify cell-state-capturing biomarkers.
- Synthetic genetic reporters were developed from 15 identified malathion-responsive promoters in Pseudomonas fluorescens SBW25.
Main Results:
- The study successfully identified 15 analyte-responsive promoters specific to malathion in Pseudomonas fluorescens SBW25.
- Synthetic genetic reporters demonstrated measurable responses to malathion, enabling its detection.
- A synthetic consortium approach enhanced malathion reporting, and the system was validated for environmental detection outside the laboratory.
Conclusions:
- The developed machine learning tool and identified promoters enable the creation of a living sensor for malathion detection.
- The engineered Pseudomonas fluorescens SBW25 serves as a promising platform for environmental diagnostics.
- The methodology is adaptable for discovering gene expression systems in diverse host organisms for various applications.
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