An autophagy-dependent tubular lysosomal network synchronizes degradative activity required for muscle remodeling
An autophagy-dependent tubular lysosomal network synchronizes degradative activity required for muscle remodeling
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DOI：
10.1242/jcs.248336
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发表时间：
2020-11-01
影响因子：
4
通讯作者：
Fujita, Naonobu
中科院分区：
文献类型：
--
作者：
Murakawa, Tadayoshi;Kiger, Amy A.;Fujita, Naonobu
溶酶体是降解内吞和自噬物质的隔室。溶酶体的形状随细胞降解的需要而改变；然而，对于不同溶酶体形态的机制或意义的了解有限。在这里，我们发现了一个广泛的小管自溶酶体网络在果蝇的腹肌重塑在变态。管状网络短暂出现并表现出降解自噬物质的能力。除Atg12和Atg8泛素样偶联系统外，自噬SNARE蛋白Syntaxin17是管状自溶酶体网络的唯一标志，其形成依赖于自噬通量和降解功能。在atg缺陷突变体中，溶酶体管化的效率与肌肉重塑的表型严重程度相关。管状网络的管腔在重塑肌的广泛区域连续均匀。总之，我们发现管状自溶酶体网络的动态扩张与发育调节的肌肉重塑所需的大量降解活动同步。
Lysosomes are compartments for the degradation of both endocytic and autophagic cargoes. The shape of lysosomes changes with cellular degradative demands; however, there is limited knowledge about the mechanisms or significance that underlies distinct lysosomal morphologies. Here, we found an extensive tubular autolysosomal network in Drosophila abdominal muscle remodeling during metamorphosis. The tubular network transiently appeared and exhibited the capacity to degrade autophagic cargoes. The tubular autolysosomal network was uniquely marked by the autophagic SNARE protein Syntaxin17 and its formation depended on both autophagic flux and degradative function, with the exception of the Atg12 and Atg8 ubiquitin-like conjugation systems. Among ATG-deficient mutants, the efficiency of lysosomal tubulation correlated with the phenotypic severity in muscle remodeling. The lumen of the tubular network was continuous and homogeneous across a broad region of the remodeling muscle. Altogether, we revealed that the dynamic expansion of a tubular autolysosomal network synchronizes the abundant degradative activity required for developmentally regulated muscle remodeling.