Pumilio1 haploinsufficiency leads to SCA1-like neurodegeneration by increasing wild-type Ataxin1 levels
- Cell. 2015 Mar 12;160(6):1087-98. doi: 10.1016/j.cell.2015.02.012.
- 1. Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
- 2. Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA.
- 3. Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
- 4. Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
- 5. Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
- 6. Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA; Dan L. Duncan Cancer Center, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.
- 7. Institute for Translational Neuroscience, Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA.
- 8. Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA.
- 9. Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA; Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA. Electronic address: [email protected].
Spinocerebellar ataxia type 1 (SCA1) is a paradigmatic neurodegenerative proteinopathy, in which a mutant protein (in this case, ATAXIN1) accumulates in neurons and exerts toxicity; in SCA1, this process causes progressive deterioration of motor coordination. Seeking to understand how post-translational modification of ATAXIN1 levels influences disease, we discovered that the RNA-binding protein PUMILIO1 (PUM1) not only directly regulates ATAXIN1 but also plays an unexpectedly important role in neuronal function. Loss of Pum1 caused progressive motor dysfunction and SCA1-like neurodegeneration with motor impairment, primarily by increasing Ataxin1 levels. Breeding Pum1(+/-) mice to SCA1 mice (Atxn1(154Q/+)) exacerbated disease progression, whereas breeding them to Atxn1(+/-) mice normalized Ataxin1 levels and largely rescued the Pum1(+/-) phenotype. Thus, both increased wild-type ATAXIN1 levels and PUM1 haploinsufficiency could contribute to human neurodegeneration. These results demonstrate the importance of studying post-transcriptional regulation of disease-driving proteins to reveal factors underlying neurodegenerative disease.