Octamer Binding Transcription Factor 1 (OCT1)

POU domain proteins contain a bipartite DNA-binding domain divided by a flexible linker that enables them to adopt various monomer configurations on DNA. The versatility of POU protein operation is additionally conferred at the dimerization level. Tomilin et al. (2000) found that the POU dimer from the OCT1 gene formed on the palindromic OCT factor recognition element, or PORE (ATTTGAAATGCAAAT), could recruit the transcriptional coactivator OBF1, whereas POU dimers formed on the consensus MORE or on MOREs from immunoglobulin heavy chain promoters failed to interact. An interaction with OBF1 was precluded since the same OCT1 residues that form the MORE dimerization interface are also used for OBF1/OCT1 interactions on the PORE.