Pax3 inhibits apoptosis of brainstem progenitor cells. Brainstem progenitor cells from P3 Ntv-a mice were cultured in vitro and infected with the indicated RCAS viruses. a qRT-PCR for Pax3 in the infected progenitor cells, normalized to Actin. Levels for Pax3-infected cells are expressed relative to RCAS-Y-infected cells, p = 0.007 paired t-test, and levels for PDGF-B + Pax3-infected cells are expressed relative to PDGF-B-infected cells, p = 0.03 paired t-test. b Caspase 3/7 activation of Pax3-infected cells is normalized to that of RCAS-Y-infected cells, p = 0.03 paired t-test, while caspase 3/7 activation of PDGF-B + Pax3-infected cells is normalized to that of PDGF-B-infected cells, p = 0.02 paired t-test. c Annexin V staining of RCAS-Pax3- versus RCAS-Y-infected progenitor cells. The percentage of Pax3-infected cells that were AnnexinV+/PI- was normalized to the percentage of RCAS-Y-infected cells that were AnnexinV+/PI-. p = 0.005, paired t-test.