Structure of the complex of C1q-like 3 protein with adhesion-GPCR BAI3.

ABSTRACT: The adhesion-GPCR Brain-specific Angiogenesis Inhibitor-3 (BAI3) plays a crucial role in organizing synapses in the brain. However, how BAI3 engages one of its ligands, the C1q-like proteins (C1qls), remains largely unexplored. Here, we present the single-particle cryo-electron microscopy (cryo-EM) structure of the C1ql3-BAI3 complex at 2.8 Å resolution. The structure reveals a hexameric configuration, where C1ql3 forms a central homotrimer that effectively captures three BAI3 molecules. These BAI3 molecules fit snugly into the grooves between the trimeric C1q domains of the C1qls, employing calcium ion (Ca²⁺)-mediated interactions that differ from previously characterized structures of C1q-like domain-mediated complexes. Furthermore, we conducted mutant analysis and cell surfac

SUBMITTER: Miao Y 

PROVIDER: S-EPMC12048575 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature