Despite the growing evidence that the macroautophagy/autophagy-related protein LC3 is localized in the nucleus, why and how it is targeted to the nucleus are poorly understood. In our recent study, we found that transcription factor seq (sequoia) interacts via its LIR motif with Atg8a, the Drosophila homolog of LC3, to negatively regulate the transcription of autophagy genes. Atg8a was found to also interact with the nuclear acetyltransferase complex subunit YL-1 and deacetylase Sirt2. Modulation of the acetylation status of Atg8a by YL-1 and Sirt2 affects the interaction between seq and Atg8a, and controls the induction of autophagy. Our work revealed a novel nuclear role for Atg8a, which is linked with the transcriptional regulation of autophagy genes.
Keywords: Acetylation; LC3/Atg8; LIR motif; autophagy; nucleus; transcription.