Unconventional secretion of α-synuclein mediated by palmitoylated DNAJC5 oligomers.
Unconventional secretion of α-synuclein mediated by palmitoylated DNAJC5 oligomers.
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由棕榈酰化的DNAJC5低聚物介导的α-突触核蛋白的非常规分泌。
DOI：
10.7554/elife.85837
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发表时间：
2023-01-10
期刊：
影响因子：
7.7
通讯作者：
Pfeffer, Suzanne R.
中科院分区：
文献类型：
--
作者：
Wu, Shenjie;Villegas, Nancy C. Hernandez;Sirkis, Daniel W.;Thomas-Wright, Iona;Wade-Martins, Richard;Schekman, Randy;Pfeffer, Suzanne R.
α-突触核蛋白（α-syn）是帕金森病（PD）患者中发现的路易体的主要成分，已被发现输出到细胞外，并可能通过细胞间传递介导其毒性。在这里，我们通过在HEK 293 T细胞中表达DnaJ同源物亚家族C成员5（DNAJC 5）来重建可溶性单体α-syn分泌。DNAJC 5经历棕榈酰化并锚定在膜上。棕榈酰化对于DNAJC 5诱导的α-syn分泌是必需的，并且分泌不受底物大小或解折叠的限制。胞质α-syn以DNAJC 5依赖性方式主动移位并隔离在内体膜隔室中。由DNAJC 5中棕榈酰化缺陷突变引起的α-syn分泌减少可以通过膜靶向肽融合诱导的DNAJC 5寡聚化来逆转。由DNAJC 5介导的内源性α-syn的分泌也在人神经母细胞瘤细胞系SH-SY 5 Y中发现，SH-SY 5 Y在视黄酸存在下分化为神经元，并且在人诱导的多能干细胞衍生的中脑多巴胺神经元中发现。我们认为DNAJC 5形成棕榈酰化的寡聚体以容纳和输出α-syn。
Alpha-synuclein (α-syn), a major component of Lewy bodies found in Parkinson’s disease (PD) patients, has been found exported outside of cells and may mediate its toxicity via cell-to-cell transmission. Here, we reconstituted soluble, monomeric α-syn secretion by the expression of DnaJ homolog subfamily C member 5 (DNAJC5) in HEK293T cells. DNAJC5 undergoes palmitoylation and anchors on the membrane. Palmitoylation is essential for DNAJC5-induced α-syn secretion, and the secretion is not limited by substrate size or unfolding. Cytosolic α-syn is actively translocated and sequestered in an endosomal membrane compartment in a DNAJC5-dependent manner. Reduction of α-syn secretion caused by a palmitoylation-deficient mutation in DNAJC5 can be reversed by a membrane-targeting peptide fusion-induced oligomerization of DNAJC5. The secretion of endogenous α-syn mediated by DNAJC5 is also found in a human neuroblastoma cell line, SH-SY5Y, differentiated into neurons in the presence of retinoic acid, and in human-induced pluripotent stem cell-derived midbrain dopamine neurons. We propose that DNAJC5 forms a palmitoylated oligomer to accommodate and export α-syn.