Gem-deficient mice were glucose intolerant.

<p><b>A</b>) Eight (8) week old Gem^−/− mice had impaired glucose homeostasis on glucose tolerance testing (GTT). <b>B</b>) Glucose tolerance was also significantly worse in 12 week old Gem^−/− mice. <b>C</b>) Glucose stimulated insulin secretion in vivo was impaired in Gem^−/− mice. <b>D</b>) Whole body insulin sensitivity was un-altered in Gem^−/− mice, as indicated by insulin tolerance tests. <b>E</b>) Insulin release in isolated islets was impaired in Gem^−/− mice. <b>F</b>) Glucose stimulated increase in ATP content was normal in Gem^−/− mice. Error bars indicate ±1SEM. * = p&lt;0.05, ** = p&lt;0.01, *** = p&lt;0.001.</p

Gem-deficient mice have impaired calcium flux.

<p><b>A</b>) Gem^+/+ islets exposed to 11.1 mM glucose establish regular calcium oscillations. <b>B</b>) In contrast, islets from Gem^−/− mice have impaired oscillations. <b>C</b>) The calculated calcium at 11.1 mM glucose is significantly lower in Gem^−/− islets. Error bars indicate ±1SEM. * = p&lt;0.05.</p

Calcium oscillations are slower in Gem^−/− mice.

<p><b>A</b>) Wild-type mice (Gem^+/+) have normal amplitude and frequency of calcium oscillations after exposure to 11.1 mM glucose. <b>B</b>) In contrast, Gem^−/− islets display smaller amplitude oscillations of lower frequency. <b>C</b>) Oscillation cycle time was slower in Gem-null islets. Error bars indicate ±1SEM. ** = p&lt;0.01.</p