FICD activity and AMPylation remodelling modulate human neurogenesis

Posttranslational modification (PTM) of proteins represents an important cellular mechanism for controlling diverse functions such as signalling, localisation or protein–protein interactions. AMPylation (also termed adenylylation) has recently been discovered as a prevalent PTM for regulating protein activity. In human cells AMPylation has been exclusively studied with the FICD protein. Here we investigate the role of AMPylation in human neurogenesis by introducing a cell-permeable propargyl adenosine pronucleotide probe to infiltrate cellular AMPylation pathways and report distinct modifications in intact cancer cell lines, human-derived stem cells, neural progenitor cells (NPCs), neurons and cerebral organoids (COs) via LC–MS/MS as well as imaging methods. A total of 162 AMP modified proteins were identified. FICD-dependent AMPylation remodelling accelerates differentiation of neural progenitor cells into mature neurons in COs, demonstrating a so far unknown trigger of human neurogenesis. Protein AMPylation is a post-translational modification whose implications in cellular physiology are not fully understood. Here the authors develop a cell-permeable AMPylation probe and use it to identify new AMP modified proteins and investigate the role of FICD in neuronal differentiation using cerebral organoids.