Atg1 phosphorylation is activated by AMPK and indispensable for autophagy induction in insects.
Atg1 phosphorylation is activated by AMPK and indispensable for autophagy induction in insects.
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DOI：
10.1016/j.ibmb.2022.103888
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发表时间：
2022-12
影响因子：
3.8
通讯作者：
Haigang Zhao;Shihui Long;Suning Liu;Dongwei Yuan;Danyan Huang;Jing Xu;Qiuqin Ma;Guirong Wang
中科院分区：
文献类型：
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作者：
Haigang Zhao;Shihui Long;Suning Liu;Dongwei Yuan;Danyan Huang;Jing Xu;Qiuqin Ma;Guirong Wang
Phosphorylation is a key post-translational modification in regulating autophagy in yeast and mammalians, yet it is not fully illustrated in invertebrates such as insects. ULK1/Atg1 is a functionally conserved serine/threonine protein kinase involved in autophagosome initiation. As a result of alternative splicing,Atg1in the silkworm,Bombyx mori, is present as three mRNA isoforms, withBmAtg1cshowing the highest expression levels. Here, we found thatBmAtg1cmRNA expression, BmAtg1c protein expression and phosphorylation, and autophagy simultaneously peaked in the fat body during larval-pupal metamorphosis. Importantly, two BmAtg1c phosphorylation sites were identified at Ser269 and Ser270, which were activated by BmAMPK, the major energy-sensing kinase, upon stimulation with 20-hydroxyecdysone and starvation; additionally, these Atg1 phosphorylation sites are evolutionarily conserved in insects. The two BmAMPK-activated phosphorylation sites in BmAtg1c were found to be required for BmAMPK-induced autophagy. Moreover, the two corresponding DmAtg1 phosphorylation sites in the fruit fly,Drosophila melanogaster, are functionally conserved for autophagy induction. In conclusion, AMPK-activated Atg1 phosphorylation is indispensable for autophagy induction and evolutionarily conserved in insects, shedding light on how various groups of organisms differentially regulate ULK1/Atg1 phosphorylation for autophagy induction.
