passages.id: split_6_test_806_passage
passages.type: progene_text
passages.text: Thus , we have characterized a novel signaling pathway ( MAPK kinase 6 / p38beta MAPK / MAPKAP-K3 ) that defines a transcriptional mechanism for the induction of the antiapoptotic protein Bcl-2 by IGF-I through the nuclear transcription factor cAMP - response element - binding protein in PC12 cells .