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bioRxiv · 10.1101/2025.11.24.690233

cAMP promotes acute lysosome biogenesis through TFEB nuclear import-export dynamics.

Bhatt, S.·Zaidi, M. A. A.·Woods, N. T. B.·Rozeveld, C. N.·Schott, M. B.
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Abstract

Cyclic adenosine monophosphate (cAMP) signaling is a major stimulus for lipid and glucose catabolism, yet catabolic processes like these can also coordinate with lysosome-dependent degradation. However, the impact of cAMP signaling on lysosomal dynamics remains unclear. Transcription factor EB (TFEB), a master regulator of lysosomal biogenesis, is regulated by stimulus-dependent nuclear-cytoplasmic shuttling through a variety of phosphorylation events. Here, we find that elevating intracellular cAMP with forskolin and IBMX induces rapid nuclear import of TFEB-GFP within 30 minutes and coincides with a transient upregulation of TFEB target lysosome genes. By 8 hours, TFEB returns to the cytoplasm, accompanied by transcriptional downregulation. Inhibition of cAMP-dependent protein kinase A (PKA) using H89 did not block nuclear import but unexpectedly caused sustained nuclear accumulation, indicating that PKA promotes TFEB nuclear export. Consistent with this, phosphoproteomic profiling revealed increased phosphorylation of a PKA-consensus motif (RRxS) during the export phase. These findings suggest that cAMP-PKA signaling plays a novel role in temporally "tuning" lysosomal gene expression by regulating TFEB nuclear-cytoplasmic shuttling. SummaryThis study reveals that cAMP signaling dynamically regulates TFEB subcellular localization, promoting transient, calcium-dependent nuclear import as well as downstream, PKA-dependent export and phosphorylation at serines 466/467. These findings uncover a novel mechanism by which cAMP stimulation fine-tunes lysosomal gene expression by regulating TFEB nuclear import and export.

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Bhatt, S., Zaidi, M. A. A., Woods, N. T. B., Rozeveld, C. N., Schott, M. B.. 2025-11-26. cAMP promotes acute lysosome biogenesis through TFEB nuclear import-export dynamics.. https://doi.org/10.1101/2025.11.24.690233

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