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bioRxiv · 10.1101/2022.12.09.519741

Structure of Toxoplasma gondii glideosome-associated connector suggests a role as an elastic element in actomyosin force generation for gliding motility

Hung, Y.-F.·Chen, Q.·Pires, I.·Rosenthal, P. B.·Kursula, I.
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Abstract

Toxoplasma gondii glideosome-associated connector (GAC) is a giant armadillo-repeat protein, essential for parasite motility and conserved across Apicomplexa. It connects actin filaments to the plasma membrane via interactions with phosphatidic acid and membrane-spanning adhesins. It is unclear how GAC contributes to gliding motility and invasion and why such a large connector is needed. We determined the crystal structure of full-length T. gondii GAC at 2.3 [A] resolution and explored its conformational space in solution using small-angle X-ray scattering and cryogenic electron microscopy. The crystal structure reveals a compact conformation but, in solution, GAC adopts both compact and extended forms. The PH domain stabilizes the compact form and may act as a switch triggered by membrane sensing. Based on its spring-like architecture, we suggest a role for GAC as an elastic element in actomyosin force generation during gliding motility and invasion.

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Hung, Y.-F., Chen, Q., Pires, I., Rosenthal, P. B., Kursula, I.. 2022-12-10. Structure of Toxoplasma gondii glideosome-associated connector suggests a role as an elastic element in actomyosin force generation for gliding motility. https://doi.org/10.1101/2022.12.09.519741

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