The activation of Lyn by GHR is thought to indirectly activate ERK. Mutations of GHR predicted to disable a conformational change brought about by GH binding impaired ERK signaling but not JAK2/STAT5 signaling. ERK signaling was demonstrated to involve the Src family kinase Lyn (Rowlinson et al. 2008) and suggested to involve Src kinase dependent activation of Phospholipase C gamma and thereby Ras, similar to a mechanism proposed by Bivona et al. (2003). ERK activation mechanisms involving Src kinases and PLCgamma have been reported for the erythropoietin, thrombopoietin and prolactin receptors (Brooks & Waters 2010).