Working hypothesis for the role of CFAP65 in acrosome biogenesis, head shaping and flagellar assembly. Schematic illustration of the mechanisms that are possibly dependent on the presence of the CFAP65. Multiple proteins may participate in the acrosome biogenesis (ZPBP and SPACA1), head shaping (MNS1) and flagellar assembly (TPPP2 and RSPH1) by forming functional complexes with CFAP65. Loss of CFAP65 leads to asthenoteratospermia characterized by an abnormal acrosome, misshapen head and malformed MS along with highly reduced motility.