Fig. 5Genetic targeting of GYS1 to abrogate glucose-6-phosphate induced activation in transgenic mice
expressing mutantPRKAG2ameliorates glycogen storage, eliminating ventricular pre-excitation, but does not
impact upon cardiac hypertrophy. Rescue of ventricular pre-excitation, but not LVH, of TGN488Imice through
genetic inhibition of glucose-6-phosphate (G6P)-stimulated glycogen synthase activity. (a) Cardiac glycogen
synthase activity in the presence (þ) or absence () of G6P in non-transgenic (NTG), TGN488I(R2M), double
transgenic TGN488I/GSR582A/R582A(DM), and homozygous knock-in GSR582A/R582A(KI) mice. (b) Cardiac glyco-
gen level. (c) Hematoxylin and eosin staining of cardiac sections illustrating absence of vacuoles in double
PRKAG2 syndrome 595