title: Silencing of SIAH1 in SH-SY5Y affects α-synuclein degradation pathway.
abstract: Seven in absentia homolog (SIAH) is a ubiquitin ligase that monoubiquitinates α-synuclein. Lewy bodies are characteristically rich in monoubiquitinated α-synuclein. We aimed to determine the effect of siRNA-SIAH1 on α-synuclein autophagy and UPS degradation in SH-SY5Y. SIAH1 expression was measured with real-time quantitative PCR and Western Blot. Cell proliferation was measured by CCK-8 assay; cell apoptosis assayed by flow cytometry. Relative protein expressions were measured by Western Blot. mRNA levels of relative protein were measured by real-time quantitative PCR. The expression of α-synuclein, LC3-II and SIAH1 were observed by confocal microscopy. We found: (1) Transfection efficiency of SIAH1-siRNA into SH-SY5 measured approximately 89% by flow cytometry. (2) siRNA silencing of SIAH1 promoted cellular proliferation and suppressed apoptosis. (3) Protein and mRNA expression of α-synuclein, LC3-II and p53 decreased after SIAH1 knockdown. E1 protein and mRNA levels increased after SIAH1 siRNA. These data show silencing SIAH1 increased cell proliferation and inhibited apoptosis in SH-SY5Y neuroblastoma cells. SIAH1 knockdown enhanced the clearance of non-aggregated α-synuclein by UPS. SIAH1 is a potential target for treatment of Parkinson's disease.
authors.affiliation: Department of Neurology, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Xu
authors.affiliation: Department of Neurology, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Xin-Zhi
authors.initials: XZ
authors.lastname: Zhang
authors.affiliation: Department of Neurology, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Yong-Jin
authors.initials: YJ
authors.lastname: Zhang
authors.affiliation: Department of Neurology, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Xiu-Ming
authors.initials: XM
authors.lastname: Li
authors.affiliation: Department of Neurology, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Zeng-Lin
authors.initials: ZL
authors.lastname: Cai
authors.affiliation: Department of Emergency, Affiliated Lianyungang Hospital of Xuzhou Medical College Lianyungang, China.
authors.forename: Xiao-Min
authors.initials: XM
authors.lastname: Li
mesh_terms: D017209:Apoptosis / Q000235:genetics*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics*; D020868:Gene Silencing; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D051844:alpha-Synuclein / Q000378:metabolism*; D000098563:Seven in Absentia Proteins
chemical_list: C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D051844:alpha-Synuclein; D044767:Ubiquitin-Protein Ligases; D000098563:Seven in Absentia Proteins
keywords: Parkinson’s disease; Seven in absentia homolog (SIAH); autophagy; ubiquitin-proteasome system (UPS); α-synuclein