NSF Postdoctoral Fellowship in Biology FY 2021: Regulation and response to environmental metals in thermophiles

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2022, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. How genes are turned on and off is a critical aspect of life.

Changes in an organism’s environment can lead to dramatic differences in how genes are turned on and off, allowing the organism to adapt and respond to different environmental stimuli. For many organisms, the mechanisms underlying a genetic response to an environmental stressor are unknown. This proposal aims to identify how a model microorganism called Thermus thermophilus control how genes are turned on and off in response to heavy metals in their environment.

This project will be conducted at the large, primarily undergraduate university, Kennesaw State University, which will provide the fellow with resources and training to conduct research, as well as ample opportunity to teach and mentor the next generation of scientists.

Thermophilic organisms are commonly used as model systems in a laboratory setting, and their proteins have considerable application in biotechnology and industry. Despite their widespread use, our understanding of the fundamental biology behind many model thermophiles is limited. Thermus thermophilus HB8 contains three Ferric Uptake Regulator (FUR) gene homologs, whose gene products are severely understudied.

The FUR family of proteins are transcriptional regulators that influence gene expression in response to regulatory metals. This research will identify the transcription regulatory networks for each Thermus thermophilus HB8 FUR homolog using the combinatorial approach, Restriction Endonuclease Protection, Selection, and Amplification (REPSA). Consensus DNA-binding sequences for each protein discovered experimentally through REPSA will be identified by massively parallel semiconductor sequencing and Multiple Em for Motif Elicitation software.

These motifs will be mapped to the organism’s genome using Find Individual Motif Occurrences. Potentially regulated genes will be validated in vitro through DNA-binding assays and in vitro transcription, as well as in vivo through gene expression analysis in mutant Thermus thermophilus HB8 strains. Results of this work will provide a better understanding of how heavy metals influence gene expression through transcription regulatory proteins in a model extremophile.

This work should also result in novel methodologies, widely applicable to transcription factor studies, that will be shared with the scientific community. Finally, this project will support the mentorship and training of several undergraduate and graduate students in the fields of microbiology and biochemistry.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.