Department of Cell Biology, Blavatnik Institute, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Department of Cell Biology, Blavatnik Institute, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Mol Cell. 2021 Dec 16;81(24):5082-5098.e11. doi: 10.1016/j.molcel.2021.10.001. Epub 2021 Oct 25.
Cell state changes are associated with proteome remodeling to serve newly emergent cell functions. Here, we show that NGN2-driven conversion of human embryonic stem cells to induced neurons (iNeurons) is associated with increased PINK1-independent mitophagic flux that is temporally correlated with metabolic reprogramming to support oxidative phosphorylation. Global multiplex proteomics during neurogenesis revealed large-scale remodeling of functional modules linked with pluripotency, mitochondrial metabolism, and proteostasis. Differentiation-dependent mitophagic flux required BNIP3L and its LC3-interacting region (LIR) motif, and BNIP3L also promoted mitophagy in dopaminergic neurons. Proteomic analysis of ATG12 iNeurons revealed accumulation of endoplasmic reticulum, Golgi, and mitochondria during differentiation, indicative of widespread organelle remodeling during neurogenesis. This work reveals broad organelle remodeling of membrane-bound organelles during NGN2-driven neurogenesis via autophagy, identifies BNIP3L's central role in programmed mitophagic flux, and provides a proteomic resource for elucidating how organelle remodeling and autophagy alter the proteome during changes in cell state.
细胞状态的改变与蛋白质组重塑有关,以适应新出现的细胞功能。在这里,我们表明,NGN2 驱动的人类胚胎干细胞向诱导神经元(iNeurons)的转化伴随着增加的 PINK1 非依赖性线粒体自噬通量,这与代谢重编程以支持氧化磷酸化是时间相关的。神经发生过程中的全局多路复用蛋白质组学揭示了与多能性、线粒体代谢和蛋白质稳态相关的功能模块的大规模重塑。分化依赖性的线粒体自噬通量需要 BNIP3L 及其 LC3 相互作用区域(LIR)基序,并且 BNIP3L 还促进了多巴胺能神经元的线粒体自噬。ATG12 iNeurons 的蛋白质组分析显示,在分化过程中内质网、高尔基体和线粒体的积累,表明神经发生过程中广泛的细胞器重塑。这项工作揭示了通过自噬在 NGN2 驱动的神经发生过程中广泛的膜结合细胞器的重塑,确定了 BNIP3L 在程序化线粒体自噬通量中的核心作用,并提供了一个蛋白质组资源,用于阐明细胞器重塑和自噬如何在细胞状态改变时改变蛋白质组。