RPS6KB1 and fragile X syndrome: Interestingly, reduction of ADCY1 function does not suppress ERK1/2 and PI3K signalling and protein synthesis in WT mice, similar to the fact that reduction/inhibition of ERK1/2, PI3K and S6K1 specifically dampens protein synthesis in FXS but not in WT neurons20, 24, 35, 37.