In addition, Ca2+-dependent tyrosine kinase Pyk2 might phosphorylate GSK3β at Tyr-216 in DM1, because Pyk2 activates GSK3β in vitro and in neuronal cells during lysophosphatidic acid (LPA)-induced neurite retraction [55,56]. This evidence concerns the gene PTK2B and myotonic dystrophy type 1.