Targeted α-synuclein mRNA degradation by PMO-based RNA-degrading chimeras

N Ning Wang S Shalakha Hegde (Department of Neurology, Johns Hopkins University School of Medicine) Z Zhichao Tang (Department of Neurology, Johns Hopkins University School of Medicine) H Haiqing Liu (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) G Gang Feng L Lili Niu B Bo Liu H Hanyu Li (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) X Xiaodi Zhang (State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital) K Kundlik Gadhave (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) R Ramhari Kumbhar (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) L Lan Jiang (Interdisciplinary Research Center for Soil Microbial Ecology and Land Sustainable Productivity in Dry Areas, Northwest A&F University) Y Yuqi Liu M Maxwell Luo (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) S Shu Zhang T Ted M. Dawson A Alexander Pantelyat (Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago) L Liana S. Rosenthal (Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago) M Mingyao Ying (Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago) X Xiaobo Mao (Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine) J Jingxin Wang (Department of Neurology, Johns Hopkins University School of Medicine)

Abstract

α-Synucleinopathies are devastating neurodegenerative diseases characterized by pathological accumulation of a neuronal protein, α-synuclein (αSyn). Lowering soluble αSyn levels is a promising therapeutic strategy to limit aggregation and neurotoxicity, but directly targeting this protein is hindered by its intrinsically disordered structure and other factors, such as its conformational heterogeneity and intracellular drug delivery barriers. Consequently, increasing attention has been directed toward targeting the SNCA transcript, which encodes αSyn. Here, we developed phosphorodiamidate morpholino oligonucleotide (PMO)-based RNA-degrading chimeras (RDCs) that selectively bind the 5′ untranslated region of SNCA messenger RNA (mRNA) and recruit RNase L for targeted RNA degradation. Through the systematic evaluation of nine RDCs, we identified and optimized 4-D1, which effectively reduced SNCA mRNA and αSyn protein expression in HEK293T cells in an RNase L-dependent manner. 4-D1 lowered SNCA transcript and αSyn protein levels in both primary cortical neurons from humanized SNCA mice and in human induced pluripotent stem cell–derived cortical neurons. This reduction prevented prion-like seeding induced by patient-derived αSyn fibrils and protected neurons from fibril-induced cytotoxicity. Finally, in vivo studies confirmed the efficacy of 4-D1 in reducing αSyn mRNA expression in humanized SNCA mice. These findings indicate that PMO-based RDCs may represent a promising therapeutic modality for α-synucleinopathies.

Article Details

Volume / Issue Vol. 123, Issue 29
Published July 21, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (21)

N

Ning Wang

S

Shalakha Hegde

Department of Neurology, Johns Hopkins University School of Medicine

Z

Zhichao Tang

Department of Neurology, Johns Hopkins University School of Medicine

H

Haiqing Liu

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

G

Gang Feng

L

Lili Niu

B

Bo Liu

H

Hanyu Li

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

X

Xiaodi Zhang

State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital

K

Kundlik Gadhave

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

R

Ramhari Kumbhar

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

L

Lan Jiang

Interdisciplinary Research Center for Soil Microbial Ecology and Land Sustainable Productivity in Dry Areas, Northwest A&F University

Y

Yuqi Liu

M

Maxwell Luo

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

S

Shu Zhang

T

Ted M. Dawson

A

Alexander Pantelyat

Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago

L

Liana S. Rosenthal

Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago

M

Mingyao Ying

Section of Genetic Medicine, Department of Medicine, Biological Sciences Division, University of Chicago

X

Xiaobo Mao

Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Department of Neurology, Johns Hopkins University School of Medicine

J

Jingxin Wang

Department of Neurology, Johns Hopkins University School of Medicine