Major component of the axial/lateral elements of synaptonemal complexes (SCS) during meiotic prophase. May be involved in the organization of chromatin by temporarily binding to DNA scaffold attachment regions. Requires SYCP3; but not SYCP1; in order to be incorporated into the axial/lateral elements. {ECO:0000269|PubMed:11463847; ECO:0000269|PubMed:16717126}.