How is RNA trafficked within living organisms? How can RNA be imaged within a living organism? Fluorescent proteins are ubiquitous tools in modern biochemistry. For over 30 years, fluorescent proteins, such as those found in the jellyfish Aequorea victoria and the sea pansy Renilla reniformis, have provided invaluable tools for biochemists to image and track arbitrary proteins of interest. In recent years, a number of researchers have been working towards developing imaging tools for RNA, such as RNA-binding proteins fused with GFP, and RNA aptamers that bind small molecules and activate their fluorescence. These tools have had considerable successes in RNA imaging and as sensors. We are working to develop advanced RNA imaging tools, towards achieving a robust, general tool for imaging arbitrary RNAs of interest – particularly in challenging systems, such as mammalian cells and whole organisms.

Eavesdropping on chemical communication. Cells use a myriad of chemical signals to communicate in a variety of ways. These range from application as diverse as quorum sensing signals that induce bacteria to form biofilms or produce bioluminescence, signals to differentiating cells in a developing organism, or neurotransmitter-mediated communication between neurons. The latter example is particularly illustrative: mammalian neurons communicate overwhelmingly using chemical signals, yet most existing sensors for probing neural activity sense voltage! We are working towards developing robust, genetically encoded fluorescent sensors for probing chemical communication between cells.

A ribozyme that synthesizes protein. RNA-protein complexes are ubiquitous in biology. The best-known RNA-protein complex (RNP) is the ribosome – as the only organelle in a cell with a known atomic-resolution structure, it is also the most well-studied RNP within a cell. We study modified ribosomes, both as a means to understand the chemical evolution of early life, as well as a tool for biotechnology and synthesis of modified proteins.