Adhesin. Required for attachment of the parasite to the host cell prior to invasion. Ensures correct folding of MIC6 and transport of the MIC6-MIC1-MIC4 complex into the micronemes. Monomer. Interacts directly with MIC4 and MIC6. Part of the MIC6-MIC1-MIC4 complex. Expression is down-regulated during bradyzoite development. The galectin-like domain has been demonstrated not to bind lactose, glucose, maltose, mannose, heparin, fucose, L-arabinose, N-acetyl-D-galactosamine, or N-acetyl-D-glucosamine. It interacts directly with the second and the third EGF-like domain of MIC6, and with part of the acidic domain. The MAR (micronemal adhesive repeat) domain was at first proposed to be TSR1-like (thrombospondin type 1-like repeat) by PubMed:9027753, but PubMed:17491595 found that this domain represents a previously unknown protein fold. This domain is jointly responsible for interacting with MIC4 and for host-cell adhesion.