Department of Biology, University of Padova, Padova, Italy; School of Biological Sciences, University of Reading, United Kingdom.
School of Pharmacy, University of Reading, Reading, United Kingdom; Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, United Kingdom.
Neurobiol Dis. 2022 Nov;174:105858. doi: 10.1016/j.nbd.2022.105858. Epub 2022 Sep 9.
Mutations in SPG11, encoding spatacsin, constitute the major cause of autosomal recessive Hereditary Spastic Paraplegia (HSP) with thinning of the corpus callosum. Previous studies showed that spatacsin orchestrates cellular traffic events through the formation of a coat-like complex and its loss of function results in lysosomal and axonal transport impairments. However, the upstream mechanisms that regulate spatacsin trafficking are unknown. Here, using proteomics and CRISPR/Cas9-mediated tagging of endogenous spatacsin, we identified a subset of 14-3-3 proteins as physiological interactors of spatacsin. The interaction is modulated by Protein Kinase A (PKA)-dependent phosphorylation of spatacsin at Ser1955, which initiates spatacsin trafficking from the plasma membrane to the intracellular space. Our study provides novel insight in understanding spatacsin physio-pathological roles with mechanistic dissection of its associated pathways.
SPG11 基因突变导致常染色体隐性遗传性痉挛性截瘫（HSP）伴胼胝体变薄，是其主要病因。先前的研究表明，spatacsin 通过形成一种类似外套的复合物来协调细胞内物质运输事件，其功能丧失会导致溶酶体和轴突运输受损。然而，调节 spatacsin 运输的上游机制尚不清楚。在这里，我们使用蛋白质组学和 CRISPR/Cas9 介导的内源性 spatacsin 标记，鉴定出一组 14-3-3 蛋白作为 spatacsin 的生理相互作用物。这种相互作用受蛋白激酶 A（PKA）依赖性磷酸化 spatacsin Ser1955 的调节，该磷酸化将 spatacsin 从质膜转运到细胞内空间。我们的研究为理解 spatacsin 的生理病理作用提供了新的见解，并对其相关途径进行了机制剖析。
