LI1035, a putative effector secreted by Lawsonia intracellularis, targets the MAPK pathway and regulates actin organizationin yeast and mammalian cells.

•Lawsonia intracellularis LI1035 was identified as the first L. intracellularis putative effector to inhibit yeast growth.•Deletion of SLT2 or KSS1 suppresses LI1035-induced growth defects in Saccharomyces cerevisiae.•LI1035 inhibits MAPK signaling cascades in yeast and mammalian cells.•LI1035 regulates actin organization in yeast and mammalian cells.