Detailed Instructions: In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
Q:  CONCLUSION : Taken together , these data suggest that TGF - beta1 modulates TPO - mediated effects on megakaryocytic proliferation by interfering with TPO - induced signal transduction , particularly by reducing the activities of MAPK ERK1 / ERK2 and STAT5 .
A:
TGF - beta1