Involvement of multimeric protein complexes in mediating the capacitation-dependent binding of human spermatozoa to homologous zonae pellucidae

► Human spermatozoa express a number of high molecular weight protein complexes. ► A subset of these complexes possesses affinity for homologous zonae pellucidae. ► Two such complexes were identified as the 20S proteasome and the TCP-1 complex. ► Our results provide insight into the mechanisms that govern sperm-egg interaction.