Alexander Pertsemlidis, PhD Co-Awarded National Science Foundation Grant.

Leonidis-Pertsemlidis II

PI: Leonidas Bleris, PhD                       Co-PI: Alexander Pertsemlidis, PhD
(UT Dallas)                                              (UT Health San Antonio)

Collaborative Research: Unraveling extracellular microRNA communication


MicroRNAs (miRNAs), in their mature forms, are small non-coding RNAs, approximately 22 nucleotides in length, that act as regulators of gene expression in cells. MiRNAs are exported from cells through hemichannels, gap junctions, and extracellular vesicles, affecting cells at great distances from the cells
responsible for their transcription. Unfortunately, reports on the intercellular transmission of miRNAs have focused on individually labeled miRNAs, leaving unanswered larger questions, such as: which miRNAs are transferred, whether the transfer is selective, whether transferred miRNAs are active, and how fast and how far they are transferred. The primary reason for this knowledge gap is that miRNAs are not labeled by the cell of origin.

Intellectual Merit:

Herein, to probe miRNA-mediated cell-cell communication, we propose to use a combination of synthetic
biology, genome editing, and chemistry approaches. We adopt a protozoan enzyme, uracil phosphoribosyltransferase (UPRT), to biosynthetically label newly synthesized RNA in “donor” cells.

Subsequently, we integrate stably in “recipient” cells novel molecular genetic circuits that can reliably detect and report miRNAs. Finally, we probe the mechanisms and properties of miRNA transfer using co-culture experiments in vitro. We propose the following specific objectives: (1) identification of miRNAs that are transferred between cells, (2) engineering of ultrasensitive miRNA sensors using synthetic biology circuits, and (3) characterization and control of miRNA transmission between cells.

This proposal is multi-disciplinary, employing methods at the interface of miRNA biology, genome editing, and synthetic biology. Novel aspects include leveraging non-mammalian proteins for use in human systems, genome editing to dissect mechanisms of miRNA transfer, and genetic circuits to sense intracellular levels of specific miRNAs.

Broader Impacts:

Our long-term goal is to address questions about how cells communicate with each other. Successful completion of the proposed work will identify miRNAs that mediate cell-cell communication and will generate a new set of resources and tools for investigating the relationship between cells in many different
models of human biology and disease. Graduate and undergraduate students will be exposed to an integrated research environment, combining theory and experiments at the intersection of biology and engineering.

The educational plan consists of several action items tightly integrated with research, including support for the International Genetically Engineered Machine (iGEM) team and developing custom educational modules for local schools (Plano and Northside ISD).  We will be collaborating with the Perot Museum in Dallas and the Witte Museum in San Antonio to organize public educational events at the interface of the biological sciences and engineering. We will recruit underrepresented minorities through the UT Academic Bridge.

Finally, considering the uncertainties in the context of the COVID-19 pandemic, a major focus for both investigators will be developing novel tools and materials for sustainable research and education.

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