The function of RSPH3 (radial spoke head 3, Ensembl gene identifier ENSG00000130363) is as follows. Functions as part of axonemal radial spoke complexes that play an important part in the motility of sperm and cilia (By similarity). Functions as a protein kinase A-anchoring protein that scaffolds the cAMP-dependent protein kinase holoenzyme. May serve as a point of convergence for MAPK and PKA signaling in cilia (PubMed:19684019). {ECO:0000250|UniProtKB:Q9DA80, ECO:0000269|PubMed:19684019}.