HDAC1 Variations Is Involved In The Pathogenic Mechanism Of Parkinson’s Disease

Background: Parkinson’s disease(PD)is the second most common neurodegenerative disease after Alzheimer’s disease(AD).The pathogenesis of PD has not been fully elucidated.Etiology of PD is likely multifactorial,and involves interplay among aging,genetic susceptibility,and environmental factors.Epigenetic modifications are the important mechanisms of PD consequence of gene and environment interaction.In recent years,many studies have shown that histone deacetylases(HDACs)are involved in the occurrence and development of various neurodegenerative diseases.Preliminary data from collaborators showed four rare HDAC1 variants(p<0.01,E418 K,T65I,R413 Q and E478V)by exome sequencing of 1,500 PD clinical samples excluding known disease-causing genes.However,whether these rare variants affect the function of HDAC1,and its role in the pathogenesis of PD,has not been elucidated.Purpose: To investigate whether the HDAC1 E418 K,T65I,R413 Q and E478 V variants,are involved in the occurrence of PD and its pathogenesis.Methods: We transfected HDAC1-WT and variants expression plasmids to N2 a cells.HDAC1 protein stability was assessed by CHX chase at 0 hr,1 hr,2 hr,4 hr and 6 hr.The subcellular localization of HDAC1 and variants was detected by immunofluorescence staining and nucleus/cytoplasm fractionation methods.The stable overexpression cell lines of HDAC1 WT and variants were constructed by G418 selection in N2 a.Subsequently,we performed RNA-seq analysis in HDAC1 WT,E418 K and T65 I stable cell lines.Integrated RNA-seq and Ch IP-seq analysis of HDAC1 and the acetylation of H3K9(a substrate of HDAC1)was performed to investigate effect of HDAC1 variants on gene expression and signaling pathways.Results: The results show that the stability of E418 K,R413Q and T65 I variants was significantly decreased compared with HDAC1 WT.The immunofluorescence revealed changes in subcellular localization of E418 K and T65 I variants.Compared with HDAC1 WT,which is almost completely distributed in the nucleus,the T65 I variant is mainly localized in the cytoplasm,and the E418 K variant tends to distribute on the nuclear membrane.RNA-seq analysis showed that T65 I and E418 K variants caused a series of gene expression changes compared with HDAC1 WT.The integrated results of Ch IP-seq analysis and transcriptomics showed that HDAC1 T65 I variant maybe affect the Wnt signaling pathway through the acetylation level of histone H3K9 involving in the occurrence of PD.Conclusion: Our results showed that HDAC1 T65 I and E418 K variants lead to changes in HDAC1 function and may be involved in pathogenesis of PD.