GGPS1 and heart failure: For instance, highly expressed GGPPS in adipocytes enhanced K-Ras geranylgeranylation to activate Ras/MAPK/Erk1/2 signalling, which inhibited insulin signalling and led to insulin resistance.308 However, downregulated GGPPS in the heart increases Rheb farnesylation to activate mTORC1 signalling, which further leads to cardiac hypertrophy and heart failure.285 By adjusting the levels of GGPP and FPP, GGPPS can play a pivotal role in governing both physiological and pathological cellular processes.