Factors and pathways affecting insulin-like growth factor (IGF1)-Akt signaling

The signaling pathway that involves insulin-like growth factor 1 (IGF1), and a variety of other components that affect the pathway, plays an important role in the regulation of skeletal muscle growth. The kinase Akt, or protein kinase B (PKB), is a central component in the pathway and is involved in both muscle synthesis, through mammalian target of rapmycin (mTOR) and glycogen synthase kinase 3B (GSK3B), and muscle degradation, through the transcription factors of the FoxO family. The pathway also involves several feedback loops such as the negative feedback of S6K, phosphorylated by mTORC1, which inhibits IRS, or the positive feedback of mTORC2, which is necessary to maximize the activation of Akt. A variety of other factors and pathways also influence the IGF1-Akt signaling pathway at various points. This pathway is based on figure 3 from Schiaffino et al.

涉及胰岛素样生长因子1（IGF1）及其影响该途径的多种其他成分的信号通路，在骨骼肌生长的调节中发挥着至关重要的作用。激酶Akt，或称蛋白激酶B（PKB），是该通路的核心组成部分，它参与肌肉合成（通过哺乳动物雷帕霉素靶蛋白mTOR和糖原合成酶激酶3B（GSK3B））以及肌肉降解（通过FoxO家族的转录因子）的过程。该通路还涉及多个反馈回路，例如由mTORC1磷酸化的S6K的负反馈，它抑制胰岛素受体底物IRS，以及mTORC2的正反馈，后者对于最大化Akt的激活至关重要。此外，众多其他因素和通路也在不同环节影响IGF1-Akt信号通路。本通路基于Schiaffino等人图3。