Histidine-dependent protein methylation is required for compartmentalization of CTP synthase

CTP synthase (CTPS) forms compartmentalized filaments in response to substrate availability and environmental nutrient status. However, the physiological role of filaments and mechanisms for filament assembly are not well understood. Here, we provide evidence that CTPS forms filaments in response to histidine influx during glutamine starvation. CTPS protein levels remained stable in the presence of histidine during nutrient deprivation, followed by rapid cell growth following nutrient replenishment. Tetramer conformation-based filament formation restricted CTPS enzyme activity duringnutrient deprivation.

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