RT Journal Article SR Electronic T1 Integrin-mediated adhesion in the unicellular holozoan Capsaspora owczarzaki JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.02.27.967653 DO 10.1101/2020.02.27.967653 A1 Helena Parra-Acero A1 Matija Harcet A1 Núria Sánchez-Pons A1 Elena Casacuberta A1 Nicholas H. Brown A1 Omaya Dudin A1 Iñaki Ruiz-Trillo YR 2020 UL http://biorxiv.org/content/early/2020/02/27/2020.02.27.967653.abstract AB In animals, cell-matrix adhesion is mainly mediated by integrins and their associated proteins. Comparative genomic analyses have shown that core components of the integrin adhesome pre-date the emergence of animals, however, whether it mediates cell adhesion in non-metazoan taxa remains unknown. Here, we investigate cell-substrate adhesion in Capsaspora owczarzaki, the closest unicellular relative of animals with the most complete integrin adhesome. Using an adhesion assay, we show that C. owczarzaki adheres to surfaces using actin-dependent filopodia. We show that integrin β2 and its associated protein vinculin localise as distinct patches in the filopodia. We also demonstrate that substrate adhesion and integrin localisation are enhanced by the ligand fibronectin. Finally, using a specific antibody for Integrin β2, we inhibited cell adhesion to a fibronectin-coated surface. Our results show that adhesion to the substrate in C. owczarzaki is mediated by integrins. This suggests that integrin-mediated adhesion pre-dates the emergence of animals.