Fig. 5

pCREB regulates high GDNF transcription by recruiting CBP to GDNF enhancer II in GBM cells. a CREB phosphorylation in NHA and U251 cells and GBM tissue as measured by western blot (n = 3). b, c Effect of overexpression of wild-type and mutant CR133 CREBs on GDNF transcription in U251 cells as assessed by real-time PCR (n = 3). d Immunofluorescence localization of pCREB and CBP in U251 cells. The scale is 100 μm (n = 1). e Binding of CREB/pCREB to CBP in U251 cells as measured by Co-IP. NC indicates no addition of antibodies in IP (n = 1). f Recruitment of CBP by pCREB binding to CREs in GDNF promoter II as determined by Re-ChIP-PCR (n = 1). g Binding of pCREB to CREs in GDNF promoter II as determined by the first ChIP-PCR (n = 3). h Binding of CBP recruited by pCREB to CREs in GDNF promoter II as determined by the second ChIP-PCR (n = 3). i Binding of CBP to CRE in GDNF enhancer II after knockdown of CREB as determined by ChIP-PCR (n = 3). jGDNF transcription in U251 cells after KG-501 treatment as determined by real-time PCR. GAPDH was used as an internal control (n = 3). All data are mean ± SD. *P < 0.05; ** and ## P < 0.01