YAP vs. TAZ: differences in expression revealed through rigorous validation of target-specific monoclonal antibodies.

The ability to reproduce scientific findings is foundational in research; yet, it is compromised in part by poorly characterized reagents, including antibodies. In this report, we describe the application of complementary validation strategies tailored for use in immunohistochemical assays in the characterization of rabbit monoclonal antibodies against YAP and TAZ, homologous and sequentially similar transcriptional effectors of the Hippo signaling pathway. A lack of antibody reagents rigorously validated for immunohistochemistry has limited the Hippo signaling research community's ability to interrogate YAP and TAZ independently in tissue. In a series of normal and diseased human tissues, we were able to demonstrate differential expression patterns of YAP and TAZ, suggesting the potential for functional differences of these proteins. These differences can now be studied in greater detail with these highly validated tools.