SAM (sterile alpha motif) domain repeat 3 of liprin/kazrin proteins is a protein-protein interaction domain. The long form of liprin/kazrin proteins contains three copies (repeats) of SAM domain. Liprin-alpha may form heterodimers with liprin-beta through their SAM domains. Liprins were originally identified as LAR (leukocyte common antigen-related) transmembrane protein-tyrosine phosphatase-interacting proteins. They participate in mammary gland development and in axon guidance. In particular, liprin-alpha is involved in formation of the presynaptic active zone; liprin-beta is involved in the maintenance of lymphatic vessel integrity. Kazrins are involved in interplay between desmosomes and in adherens junctions; additionally they play a role in regulation of intercellular differentiation, junction assembly, and cytoskeletal organization.
Jiyao W et al.(2023). "The conserved domain database in 2023.",