Nuclear import adapter that specifically recruits the two functionally and topologically linked ribosomal proteins RPL5 and RPL11 (encoded by RPL11A and RPL11B). Guarantees that this cargo pair remains bound together from the time of synthesis in the cytoplasm until delivery to the nascent 5S rRNA in the nucleus. Forms a heterotrimeric complex with RPL5 and RPL11A or RPL11B. Interaction of this complex with KAP104 allows the nuclear import of the heterotrimer. The SYO1/RPL11/RPL5 complex is transported into the nucleus by KAP104. Present with 2600 molecules/cell in log phase SD medium.