Genetic loss of function of Ptbp1 does not induce glia-to-neuron conversion in retina
Thanh Hoang,
Dong Won Kim,
Haley Appel,
Nicole A. Pannullo,
Patrick Leavey,
Manabu Ozawa,
Sika Zheng,
Minzhong Yu,
Neal S. Peachey,
Seth Blackshaw
Affiliations
Thanh Hoang
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Corresponding author
Dong Won Kim
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Corresponding author
Haley Appel
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
Nicole A. Pannullo
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
Patrick Leavey
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
Manabu Ozawa
Center for Experimental Medicine and Systems Biology, University of Tokyo, Tokyo, Japan
Sika Zheng
Division of Biomedical Sciences, University of California, Riverside, CA, USA
Minzhong Yu
Department of Ophthalmic Research, Cole Eye Institute, Cleveland, OH, USA; Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
Neal S. Peachey
Department of Ophthalmic Research, Cole Eye Institute, Cleveland, OH, USA; Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
Seth Blackshaw
Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Corresponding author
Summary: Direct reprogramming of glia into neurons is a potentially promising approach for the replacement of neurons lost to injury or neurodegenerative disorders. Knockdown of the polypyrimidine tract-binding protein Ptbp1 has been recently reported to induce efficient conversion of retinal Mϋller glia into functional neurons. Here, we use a combination of genetic lineage tracing, single-cell RNA sequencing (scRNA-seq), and electroretinogram analysis to show that selective induction of either heterozygous or homozygous loss-of-function mutants of Ptbp1 in adult retinal Mϋller glia does not lead to any detectable level of neuronal conversion. Only a few changes in gene expression are observed in Mϋller glia following Ptbp1 deletion, and glial identity is maintained. These findings highlight the importance of using genetic manipulation and lineage-tracing methods in studying cell-type conversion.
