NT2 cells show low level of endogenous REST/NRSF-dependent promoter repression (A and B). NT2, PC12 and HeLa cells were transfected with pNaCh or pNaChΔRE and analyzed as described in Materials and Methods. The data are represented as percent promoter activity (A; pNaChΔRE = 100%) and REST-dependent repression (B; pNaChΔRE/pNaCh; no repression is denoted as a relative value of 1). REST-VP16 can counter REST/NRSF-dependent repression and stimulate neuronal promoters (C). NT2 cells were transfected with pNaCh in the presence of pcDNA3.1, pGFP, pREST, pREST.DBD, pGal4-VP16 and pREST-VP16 and the NaCh promoter activity was determined as described in Materials and Methods.