Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India.
Curr Opin Cell Biol. 2022 Oct;78:102121. doi: 10.1016/j.ceb.2022.102121. Epub 2022 Aug 26.
Some organelles show a spatial gradient of maturation along the neuronal process where more mature organelles are found closer to the cell body. This gradient is set up by progressive maturation steps that are aided by differential organelle distribution as well as transport. Autophagosomes and endosomes mature as they acquire lysosomal membrane proteins and decrease their luminal pH as they are retrogradely transported towards the cell body. The acquisition of lysosomal proteins along the neuronal processes likely occurs through fusion or membrane exchange events with Golgi-derived donor transport carriers that are transported anterogradely from the cell body. The mechanisms by which endosomes and autophagosomes mature might be applicable to other organelles that are transported along neuronal processes. Defects in axonal transport may also contribute to the accumulation of immature organelles in neurons. Such accumulations have been seen in neurons of neurodegenerative models.
有些细胞器在神经元突起中呈现出成熟的空间梯度，更成熟的细胞器靠近细胞体。这个梯度是通过渐进的成熟步骤建立的，这些步骤通过细胞器的差异分布和运输来辅助。自噬体和内体在逆行运输向细胞体的过程中，通过获得溶酶体膜蛋白和降低腔内部 pH 值而成熟。溶酶体蛋白沿着神经元突起的获得可能是通过与高尔基衍生的供体运输载体融合或膜交换事件发生的，这些载体从细胞体顺行运输。内体和自噬体成熟的机制可能适用于沿着神经元突起运输的其他细胞器。轴突运输缺陷也可能导致神经元中未成熟细胞器的积累。这种积累在神经退行性模型的神经元中已经被观察到。
