Fluorescence-Based Functional Assay for Wnt/β-Catenin Signaling Activity. (November 2002)

• Record Type: Journal Article
• Authors: Zhou, L.; An, N.; Jiang, W.; Haydon, R.; Cheng, H.; Zhou, Q.; Breyer, B.; Feng, T.; He, T.-C.
• Is Part Of: Biotechniques. Volume 33:Number 5(2002)
• Page Start: 1126
• Page End: 1135
• Publication Date: 2002-11
• Subjects: Biology, Experimental -- Periodicals; Molecular biology -- Periodicals; Medical technology -- Periodicals; Biology, Experimental; Medical technology; Molecular biology; Clinical Laboratory Techniques -- Periodicals; Research -- Periodicals; Medical Laboratory Science -- Periodicals; Periodicals; Electronic journals; 570
• DOI: 10.2144/02335dd07
• Languages: English
• ISSNs: 0736-6205

Abstract

Aberrant activation of β-catenin signaling has been implicated in the development of human cancers. As a Wnt signal transducer, β-catenin forms a complex with the lymphocyte enhancer-binding factor/T cell factor transcription factor and activates downstream targets that promote cell proliferation. Here we developed a Wnt-dependent β-catenin-mediated heterologous transactivation system, which consisted of a chimeric transcription factor constructed by fusing the GAL4 DNA-binding domain with the full-length β-catenin, and a GAL4-responsive reporter expressing GFP. The chimeric transcription factor was highly unstable and exerted no detectable transactivating effect on the GAL4-responsive reporter. However, lithium and Wnt1 significantly stabilized this chimeric transactivator, indicating that this transactivation system is regulated by β-catenin in a Wnt-responsive fashion. Thus, this transactivation system could be used as a functional reporter to identify potential upstream factors that deregulate β-catenin signaling during tumorigenesis, as well as to screen for potential anti-cancer agents that specifically inhibit β-catenin signaling in human tumors.