| RFX 1 and NF 1 associate with P sequences of the human growth hormone locus in pituitary chromatin . ^^^ Disruption of the RFX site within 263P blunts repressor activity in transfected GC cells ; however , repression is only abolished when both PSE A / RFX and PSE B / NF 1 sites are mutated . ^^^ The capacity of RFX and NF 1 to participate in a novel common complex is further suggested by coimmunoprecipitation of RFX 1 and epitope tagged NF 1 family members . ^^^ Finally , we confirm the association of NF 1 and RFX 1 with P sequences in human pituitary tissue by chromatin immunoprecipitation . ^^^ |