Tingting Xu

By Dan Close, Tingting Xu, Abby Smartt, Sarah Price, Steven Ripp and Gary Sayler

Part of the book: Genetic Engineering

By Tingting Xu, Michael Conway, Ashley Frank, Amelia Brumbaugh, Steven Ripp and Dan Close

Autobioluminescent cellular models are emerging tools for drug discovery that rely on the expression of a synthetic, eukaryotic‐optimized luciferase that does not require an exogenous chemical substrate to produce its resultant output signal. These models can therefore self‐modulate their output signals in response to metabolic activity dynamics and avoid the sample destruction and intermittent data acquisition limitations of traditional fluorescent or chemically stimulated bioluminescent approaches. While promising for reducing drug discovery costs and increasing data acquisition relative to alternative approaches, these models have remained relatively untested for drug discovery applications due to their recent emergence within the field. This chapter presents a history and background of these autobioluminescent cellular models to offer investigators a generalized point of reference for understanding their capabilities and limitations and provides side‐by‐side comparisons between autobioluminescent and traditional, substrate‐requiring toxicology screening platforms for pharmaceutically relevant three‐dimensional and high‐throughput screening applications to introduce investigators to autobioluminescence as a potential new drug discovery toolset.

Part of the book: Special Topics in Drug Discovery

By Tingting Xu, Andrew Kirkpatrick, Jody Toperzer, Marvin Steven Furches, Steven Ripp, Gary Sayler and Dan Close

Overexposure to endocrine disruptor chemicals (EDCs) can result in serious health problems, yet they are commonly found in everyday items such as pesticides, personal care products, nutritional supplements, and plastics. The U.S. Environmental Protection Agency, along with other such agencies from around the world, have therefore mandated that new approaches be designed to screen these products for the presence of EDCs. However, despite the presence of several types of extant EDC detection assays, there still exists a backlog approaching 87,000 chemicals currently awaiting screening. Autobioluminescent detection systems, which utilize cellular bioreporters capable of autonomously modulating bioluminescent signals without the need for external stimulation or investigator interaction, provide an attractive means for addressing this backlog because of their reduced performance costs and increased throughput relative to alternative assay systems. This chapter reviews the variety of existing EDC detection assays and evaluates the performance of a representative autobioluminescent estrogen-responsive EDC bioreporter to provide an overview of how autobioluminescence can be used to improve EDC detection using in vitro assay systems.

Part of the book: Endocrine Disruptors

By Andrew Kirkpatrick, Tingting Xu, Steven Ripp, Gary Sayler and Dan Close

This chapter explores the history of the bioengineering advances that have been applied to common luciferase enzymes and the improvements that have been accomplished by this work. The primary focus is placed on firefly luciferase (FLuc), Gaussia luciferase (GLuc), Renilla luciferase (RLuc), Oplophorus luciferase (OLuc; NanoLuc), and bacterial luciferase (Lux). Beginning with the cloning and exogenous expression of each enzyme, their step-wise modifications are presented and the new capabilities endowed by each incremental advancement are highlighted. Using the historical basis of this information, the chapter concludes with a prospective on the overall impact these advances have had on scientific research and provides an outlook on what capabilities future advances could unlock.

Part of the book: Bioluminescence