Related Experiment Video
Updated: May 9, 2026
A Multiplexed Luciferase-based Screening Platform for Interrogating Cancer-associated Signal Transduction in Cultured Cells
Published on: July 3, 2013
A novel reporter system for molecular imaging and high-throughput screening of anticancer drugs
Jingping Xie1, Chunxia Wang, John Virostko
1Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232, USA. Jingping.Xie@vanderbilt.edu
Abstract:
Apoptosis is irreversible programmed cell death, characterized by a cellular cascade activation of caspase 3, which subsequently degrades proteins and other components of cells with a motif sequence. Here we report a novel reporter system to detect apoptosis, growth arrest, and cell death based on controlled and self-amplified protein degradation. The key element of the reporter system is an apoptotic sensor chimerical protein which consists of three components: procaspase 3, ubiquitin (Ub), and a strong consensus sequence of N-degron. Between each of these units is a DEVD (Asp-Glu-Val-Asp) sequence, which acts as the cleavage target of caspase 3. This non-conventional signal loss approach is much more sensitive than other native methods that are based on signal gain. The superior sensitivity is demonstrated by its effective application in 386-well high-throughput screening (HTS) with low drug concentrations and a short incubation time. The HTS selection process using this reporter system is very simple and economic. The simplicity eliminates potential errors introduced by multiple steps; there is no need for any substrate. Furthermore, the cells in the assay need not be disrupted, and the morphology of the cells can provide additional information on mechanisms. After HTS, the intact cells can also be used for other analytic analysis. This system thus has a potentially important role in the discovery and development of new anticancer drugs. It also appears to be very versatile, can be used both in vitro and in vivo with different linked reporter genes, and can be used for a variety of imaging applications.
Insights
A novel reporter system detects apoptosis, growth arrest, and cell death using a self-amplified protein degradation approach. This highly sensitive method enables efficient high-throughput screening for new anticancer drug discovery.
Area of Science:
- Biochemistry
- Cell Biology
- Drug Discovery
Background:
- Apoptosis, or programmed cell death, is a critical biological process.
- Caspase 3 activation initiates a cascade leading to cellular degradation.
- Existing methods for detecting apoptosis often lack sensitivity or require cell lysis.
Purpose of the Study:
- To develop a novel, highly sensitive reporter system for detecting apoptosis, growth arrest, and cell death.
- To create a system based on controlled and self-amplified protein degradation.
- To facilitate high-throughput screening (HTS) for anticancer drug discovery.
Main Methods:
- Engineered an apoptotic sensor chimera protein comprising procaspase 3, ubiquitin (Ub), and an N-degron sequence.
- Incorporated DEVD sequences as caspase 3 cleavage targets between protein components.
- Utilized a signal-loss detection mechanism for enhanced sensitivity in HTS.
Main Results:
- The reporter system demonstrated superior sensitivity compared to signal-gain methods.
- Successfully applied in a 386-well HTS assay with low drug concentrations and short incubation times.
- The system allows for analysis of intact cells, preserving morphology for mechanistic insights.
Conclusions:
- The novel reporter system offers a simple, economic, and sensitive approach for apoptosis detection.
- It is versatile for in vitro and in vivo applications, including imaging.
- The system holds significant potential for accelerating the discovery and development of novel anticancer therapeutics.
