Autophagy-dependent splicing control directs translation toward inflammation during senescence

The cellular proteome determines the functional state of cells and is often skewed to direct pathological conditions. Autophagy shapes cellular proteomes primarily through lysosomal degradation of either damaged or unnecessary proteins. Here, we show that Autophagy directs the senescence-specific translatome to fuel inflammation by coupling selective protein degradation with alternative splicing. RNA splicing is significantly altered during senescence, some of which surprisingly depend on Autophagy, including exon 5 skipping of the translation regulator EIF4H. Systematic translatome profiling indicates that this event is key to the translational bias toward inflammation in senescence. Autophagy promotes these changes by selectively degrading the splicing regulator splicing factor proline and glutamine rich (SFPQ) via the Autophagy receptor NBR1. These autophagy-centric inflammatory controls appear to be conserved during human tissue aging and Cancer. Our work highlights the role of Autophagy in the on-demand functional remodeling of cellular proteomes as well as the crosstalk between Autophagy, alternative splicing, and inflammatory translation.

RNA homeostasis; aging; alternative splicing; autophagy; cancer; cellular senescence; inflammation; protein translation; selective autophagy.