Ai Lab

Laboratory of Protein Engineering for Bioactivity Imaging

The Ai laboratory uses interdisciplinary approaches in biophysics, chemical biology, bioengineering, and electrophysiology to study and manipulate complex biological systems, with a focus on the development of novel molecular biosensors to peer into cells and organisms to understand communications.

We use a collection of technologies, such as protein engineering, fluorescence imaging, bioluminescence imaging, synthetic chemistry, and electrophysiology to dissect biological pathways related to metabolism, redox signaling, and neurotransmission.

Our immediate goal is to monitor biological signaling in real time with excellent spatial resolution and molecular precision in physiologically relevant environments. Our long-term goal is to apply these new probes to live cells and rodent models to understand communications relevant to diabetes, cognition and behavior, and neurological disorders.

addgene: the nonprofit plasmid repository


We are currently working with Addgene a nonprofit plasmid repository, to deposit frequently requested plasmids. Also see "Practical Notes for teLuc-DTZ and Antares2-DTZ".
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A High-Performance Fluorescent Biosensor for Imaging Physiological Peroxynitrite

In our recent Cell Chemical Biology paper, we report pnGFP-Ultra as a genetically encoded biosensor with an ~110-fold turn-on response. pnGFP-Ultra exhibits high selectivity and sensitivity toward peroxynitrite and robustly detects peroxynitrite in macrophages and primary glial cells. In addition, we describe an optimized plasmid-based system which increases noncanonical amino acid incorporation in mammalian cells.
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A Fast High-Affinity Fluorescent Serotonin Biosensor Engineered from a Tick Lipocalin

Serotonin (5-HT) is an important signaling monoamine. In our recent Nature Methods paper, we report a green fluorescent, genetically encoded serotonin sensor (G-GESS) from a 5-HT-binding lipocalin in the soft tick. G-GESS shows fast response kinetics and high affinity, specificity, brightness, and photostability. We used G-GESS to image 5-HT dynamics in vitro and in behaving mice.
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Congratulations to Hao and Shengyu for becoming Ph.D. candidates

Both Hao Zhang and Shengyu Zhao passed their candidacy exam with a grade of "High Pass". "High Pass" is reserved for a small percentage of students and this is a…

Nature Chem Bio: A general strategy to red-shift green fluorescent protein-based biosensors

In our recent Nature Chemical Biology paper, we describe a general and convenient method, which uses a genetically encoded noncanonical amino acid, 3-aminotyrosine, to red-shift green fluorescent protein-like proteins and…

Highly Cited Paper (top 1% in Chemistry)

As of 2020, our manuscript "Reaction-Based Genetically Encoded Fluorescent Hydrogen Sulfide Sensors" is a highly cited paper (in the top 1% of the academic field of Chemistry based on a…

Shen Zhang defended Ph.D. thesis

Congratulations to Shen Zhang, who have successfully defended his thesis for a Ph.D. degree in Chemistry. Shen gave an impressive presentation via ZOOM on April 14, 2020.

Tianchen, Ying, and Yu became PhD candidates

Recently, Tianchen (Biophysics), Ying (Biophysics), and Yu (Chemistry) all passed their oral exams and became PhD candidates in their respective graduate programs. Congratulations!

Ai named Charter Member of NIH Study Section

Dr. Ai has been appointed by NIH as a charter member of the Imaging Guided Interventions and Surgery – IGIS study section. Dr. Ai will hold the position four years, attending…

Lab Location

Pinn Hall - Rm. 4013-4020, 1340 Jefferson Park Avenue, Charlottesville, VA 22908