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bioRxiv · 10.1101/2025.09.17.676727

De novo Golgi biogenesis requires coordinated transactivation of a Golgi regulon

Abstract

The Golgi apparatus expands during differentiation and high secretory demand, yet the transcriptional control of its biogenesis remains poorly defined. Here, we developed a targeted enzymatic ablation method to eliminate the Golgi and trigger de novo organelle formation. Single-cell RNA-seq of cells rebuilding Golgi revealed an orchestrated induction of a broad Golgi gene network coinciding with structural and functional organelle maturation. This gene set spans all Golgi sub-compartments and functions, including glycosylation, trafficking, and ion transport, thus supporting the concept of a unified Golgi regulon, enabling the simultaneous expression of components required for the organelle structural and functional integrity. Through promoter analysis and RNAi screening, we identified CREB3L1 as a key transcriptional regulator critical for Golgi gene activation and organelle reformation. These findings indicate that CREB3L1-dependent transcriptional mechanisms orchestrate a complete Golgi biogenesis program that may be essential for organelle regeneration and for secretory pathway plasticity during physiological remodeling.

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BibTeXRIS

Forno, F., Abete, D., Polishchuk, E., Bujanda Cundin, X., Renda, F., Crispino, R., Salzano, J., Petruzzelli, R., De Cegli, R., Sofia, M., Sorrentino, N. C., Vaccaro, L., Cacchiarelli, D., Verbakel, J., De Boer, J., Goud, B., Khodjakov, A., Perez, F., Polishchuk, R.. 2025-09-17. De novo Golgi biogenesis requires coordinated transactivation of a Golgi regulon. https://doi.org/10.1101/2025.09.17.676727

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