MST1 and nephronophthisis: Furthermore, MST1/2-SAV1 associates with the NPHP complex (proteins encoded by genes that are a hot spot for mutations in the nephronophthisis (NPHP)-related ciliopathic disorders), that regulates the loading of cargoes into intraflagellar transport (IFT) complexes at the cilium transition zone, and promotes cilia assembly [189].