A Yeast Model of FUS/TLS-Dependent Cytotoxicity

• Main Authors: Ju, Shulin (Author), Tardiff, Daniel F. (Contributor), Han, Haesun (Contributor), Divya, Kanneganti (Author), Zhong, Quan (Author), Maquat, Lynne E. (Author), Bosco, Daryl A. (Author), Hayward, Lawrence J. (Author), Brown, Robert H. (Author), Lindquist, Susan (Contributor), Ringe, Dagmar (Author), Petsko, Gregory A. (Author)
• Other Authors: move to dc.description.sponsorship (Contributor), Massachusetts Institute of Technology. Department of Biology (Contributor), Whitehead Institute for Biomedical Research (Contributor)
• Format: Article
• Language: English
• Published: Public Library of Science, 2011-08-31T19:58:32Z.
• Subjects: Article
• Online Access: Get fulltext

 FUS/TLS is a nucleic acid binding protein that, when mutated, can cause a subset of familial amyotrophic lateral sclerosis (fALS). Although FUS/TLS is normally located predominantly in the nucleus, the pathogenic mutant forms of FUS/TLS traffic to, and form inclusions in, the cytoplasm of affected spinal motor neurons or glia. Here we report a yeast model of human FUS/TLS expression that recapitulates multiple salient features of the pathology of the disease-causing mutant proteins, including nuclear to cytoplasmic translocation, inclusion formation, and cytotoxicity. Protein domain analysis indicates that the carboxyl-terminus of FUS/TLS, where most of the ALS-associated mutations are clustered, is required but not sufficient for the toxicity of the protein. A genome-wide genetic screen using a yeast over-expression library identified five yeast DNA/RNA binding proteins, encoded by the yeast genes ECM32, NAM8, SBP1, SKO1, and VHR1, that rescue the toxicity of human FUS/TLS without changing its expression level, cytoplasmic translocation, or inclusion formation. Furthermore, hUPF1, a human homologue of ECM32, also rescues the toxicity of FUS/TLS in this model, validating the yeast model and implicating a possible insufficiency in RNA processing or the RNA quality control machinery in the mechanism of FUS/TLS mediated toxicity. Examination of the effect of FUS/TLS expression on the decay of selected mRNAs in yeast indicates that the nonsense-mediated decay pathway is probably not the major determinant of either toxicity or suppression.