Inter-filament interaction between IMPDH and CTPS cytoophidia

Inosine monophosphate dehydrogenase (IMPDH) and cytidine triphosphate synthase (CTPS) are two metabolic enzymes that perform rate-limiting steps in the de novo synthesis of purine and pyrimidine nucleotides, respectively. It has been shown that IMPDH and CTPS can comprise a filamentous macrostructur...

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Bibliographic Details
Main Authors: Chang, C-C, Keppeke, GD, Sung, L-Y, Liu, J-L
Format: Journal article
Language:English
Published: John Wiley and Sons, Inc. 2018
Description
Summary:Inosine monophosphate dehydrogenase (IMPDH) and cytidine triphosphate synthase (CTPS) are two metabolic enzymes that perform rate-limiting steps in the de novo synthesis of purine and pyrimidine nucleotides, respectively. It has been shown that IMPDH and CTPS can comprise a filamentous macrostructure termed the cytoophidium, which may play a role in regulation of their catalytic activity. Although these two proteins may colocalise in the same cytoophidium, how they associate with one another is still elusive. As reported herein, we established a model HeLa cell line co-expressing OFP-tagged IMPDH2 and GFP-tagged CTPS1 and recorded the assembly, disassembly and movement of the cytoophidium in live cells. Moreover, by using super-resolution confocal imaging, we demonstrate how IMPDH- and CTPS-based filaments are aligned or intertwined in the mixed cytoophidium. Collectively, our findings provide a panorama of cytoophidium dynamics and suggest that IMPDH and CTPS cytoophidia may coordinate by inter-filament interaction. This article is protected by copyright. All rights reserved.