DOI: 10.1002/ame2.12129
Knock in of a hexanucleotide repeat expansion in the C9orf72 gene induces ALS in rats
Wei Dong1
Li Zhang2
Caixian Sun3
Xiang Gao3
Feifei Guan3
Jing Li4
Wei Chen3
Yuanwu Ma4
Lianfeng Zhang1
1.Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China;Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China2.Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, China;Beijing Engineering Research Center for Experimental Animal Models of Human Diseases, Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China3.Key Laboratory of Human Disease Comparative Medicine, National Health Commission of China (NHC), Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China4.Beijing Engineering Research Center for Experimental Animal Models of Human Diseases, Institute of Laboratory Animal Science, Peking Union Medicine College, Chinese Academy of Medical Sciences, Beijing, China
摘要：Background: The GGGGCC (G4C2) repeat expansion in the human open reading frame 72 on chromosome 9, C9orf72, is the most common cause of amyotrophic lat-eral sclerosis (ALS). Studies in transgenic mouse models have linked the pathogenic mechanism of G4C2 repeat expansion to RNA foci or the accumulation of unnatural dipeptide repeats in neurons. However, only one of the existing transgenic mouse lines developed typical ALS. Methods: C9orf72 knockin rats were generated by knockin of 80 G4C2 repeats with human flanking fragments within exon1a and exon1b at the rat C9orf72 locus. Protein expression was detected by western blot. Motor coordination and grip force were measured using a Rotarod test and a grip strength test. Neurodegeneration was as-sessed by Nissl staining with cresyl violet. Results: C9orf72 haploinsufficiency reduced C9orf72 protein expression 40％ in the cerebrum, cerebellum and spinal cords from knockin rats (P?<?.05). The knockin (KI) rats developed motor deficits from 4?months of age. Their falling latencies and grip force were decreased by 67％ (P?<?.01) and 44％ (P?<?.01), respectively, at 12?months of age compared to wild-type (WT) mice. The knockin of the hexanucleotide repeat expansion (HRE) caused a 47％ loss of motor neurons in the spinal cord (P?<?.001) and 25％ (5/20) of female KI rats developed hind limb paralysis at 13 to 24?months. Conclusion: Motor defects in KI rats may result from neurotoxicity caused by HRE and the resulting reduction in C9orf72 protein due to haploinsufficiency. These KI rats could be a useful model for investigating the contributions of loss-of-function to neurotoxicity in C9orf72-related ALS.
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论文发表日期：2020-09-25
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：8( 237-244 )
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