PT  - JOURNAL ARTICLE
AU  - Amit Kumar
AU  - Oscar Vadas
AU  - Nicolas Dos Santos Pacheco
AU  - Xu Zhang
AU  - Kin Chao
AU  - Nicolas Darvill
AU  - Helena Ø. Rasmussen
AU  - Yingqi Xu
AU  - Gloria Lin
AU  - Fisentzos A Stylianou
AU  - Jan Skov Pedersen
AU  - Sarah L. Rouse
AU  - Marc L. Morgan
AU  - Dominique Soldati-Favre
AU  - Steve Matthews
TI  - Structural and regulatory insights into the glideosome-associated connector from <em>Toxoplasma gondii</em>
AID  - 10.1101/2023.01.23.525158
DP  - 2023 Jan 01
TA  - bioRxiv
PG  - 2023.01.23.525158
4099  - http://biorxiv.org/content/early/2023/01/23/2023.01.23.525158.short
4100  - http://biorxiv.org/content/early/2023/01/23/2023.01.23.525158.full
AB  - The phylum of Apicomplexa groups intracellular parasites that employ substratedependent gliding motility to invade host cells, egress from the infected cells and cross biological barriers. The glideosome associated connector (GAC) is a conserved protein essential to this process. GAC facilitates the association of actin filaments with surface transmembrane adhesins and the efficient transmission of the force generated by myosin translocation of actin to the cell surface substrate. Here, we present the crystal structure of Toxoplasma gondii GAC and reveal a unique, supercoiled armadillo repeat region that adopts a closed ring conformation. Characterisation of the membrane binding interface within the C-terminal PH domain as well as an N-terminal fragment necessary for association with F-actin suggest that GAC adopts multiple conformations. A multi-conformational model for assembly of GAC within the glideosome is proposed.Competing Interest StatementThe authors have declared no competing interest.