Fracchiolla Dorotea, Sawa-Makarska Justyna, Martens Sascha
a Department of Biochemistry and Cell Biology , Max F. Perutz Laboratories (MFPL), University of Vienna, Vienna Biocenter (VBC) , Vienna , Austria.
Autophagy. 2017 May 4;13(5):978-979. doi: 10.1080/15548627.2016.1277311. Epub 2017 Jan 25.
Selective macroautophagy/autophagy mediates the selective delivery of cytoplasmic cargo material via autophagosomes into the lytic compartment for degradation. This selectivity is mediated by cargo receptor molecules that link the cargo to the phagophore (the precursor of the autophagosome) membrane via their simultaneous interaction with the cargo and Atg8 proteins on the membrane. Atg8 proteins are attached to membrane in a conjugation reaction and the cargo receptors bind them via short peptide motifs called Atg8-interacting motifs/LC3-interacting regions (AIMs/LIRs). We have recently shown for the yeast Atg19 cargo receptor that the AIM/LIR motifs also serve to recruit the Atg12-Atg5-Atg16 complex, which stimulates Atg8 conjugation, to the cargo. We could further show in a reconstituted system that the recruitment of the Atg12-Atg5-Atg16 complex is sufficient for cargo-directed Atg8 conjugation. Our results suggest that AIM/LIR motifs could have more general roles in autophagy.
选择性巨自噬/自噬介导细胞质货物物质通过自噬体选择性地运输到溶酶体区室进行降解。这种选择性由货物受体分子介导,这些受体分子通过同时与货物和膜上的Atg8蛋白相互作用,将货物连接到吞噬泡(自噬体的前体)膜上。Atg8蛋白通过结合反应附着在膜上,货物受体通过称为Atg8相互作用基序/LC3相互作用区域(AIMs/LIRs)的短肽基序与它们结合。我们最近发现,对于酵母Atg19货物受体,AIM/LIR基序还用于将刺激Atg8结合的Atg12-Atg5-Atg16复合物募集到货物上。我们可以在重组系统中进一步证明,Atg12-Atg5-Atg16复合物的募集足以实现货物定向的Atg8结合。我们的结果表明,AIM/LIR基序可能在自噬中具有更广泛的作用。