The binding of Sonig Hedgehog (Shh) to its receptor Patched (Ptch) causes the activation of Smo. In the previously known canonical pathways Smo in turn regulates gene expression via Gli transcription factors. In the newly discovered pathway, the activation triggers the influx of calcium and leads to the activation of various calcium-dependent enzymes, such as the calmodulin kinase (Camkk2), AMP-activated kinase (Ampk) and liver kinase B1 (Lkb1). This signalling pathway can also be specifically activated by agents such as cylcopamine. Both signal pathways change the metabolisms of muscle and brown fat cells, enabling them to rapidly absorb and utilise large quantities of glucose.