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bioRxiv · 10.1101/2024.06.16.599241

Filament structures unveil the dynamic organization of human acetyl-CoA 1 carboxylase

Zhou, F.·Zhang, Y.·Zhu, Y.·Zhou, Q.·Shi, Y.·Hu, Q.
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Abstract

Human acetyl-CoA carboxylases (ACCs) catalyze the carboxylation of acetyl-CoA, which is the rate-limiting step in fatty acid synthesis. The molecular mechanism underlying the dynamic organization of ACCs is largely unknown. Here, we determined the cryo-EM structure of human ACC1 in its inactive state, which forms a unique filament structure and is in complex with acetyl-CoA. We also determined the cryo-EM structure of human ACC1 activated by dephosphorylation and citrate treatment, at a resolution of 2.55 [A]. Notably, the covalently linked biotin binds to a site that is distant from the acetyl-CoA binding site when acetyl-CoA is absent, suggesting a potential coordination between biotin binding and acetyl-CoA binding. These findings provide insights into the structural dynamics and regulatory mechanisms of human ACCs. TeaserCryo-EM structures reveal how human acetyl-CoA carboxylase 1 changes shape to control its activity.

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Zhou, F., Zhang, Y., Zhu, Y., Zhou, Q., Shi, Y., Hu, Q.. 2024-06-17. Filament structures unveil the dynamic organization of human acetyl-CoA 1 carboxylase. https://doi.org/10.1101/2024.06.16.599241

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