Molecular characterization of BRSK2 and BRSK1 kinases as negative regulators of the NRF2 transcription factor

We found that the understudied Brain Specific Kinase 2 and 1 (BRSK2/1) proteins suppress NRF2-dependent transcription and NRF2 protein levels in a kinase-dependent fashion. Integrative phosphoproteomic screens, RNAseq profiling and follow-up validation studies revealed BRSK2/1-driven activation of AMPK and suppression of MTOR signaling. BRSK2 over-expression suppressed global protein synthesis and decreased ribosome-RNA associations, which results in decreased NRF2 protein levels. Overall, our data establish the BRSK1 and BRSK2 kinases as negative regulators of NRF2 via the AMPK/MTOR signaling axis. Evaluation of BRSK2/1 induced changes in RNA via overexpression in HEK293Ts.