Selection of NPC specific Transcription factors

To construct a candidate pool of NPC specific transcription factor (TF), we selected the genes expressed at relatively high levels in NPCs by comparing them to mixed RNA derived from multiple organs, eliminating housekeeping genes. As result, 160 putative NPC specific TFs were selected. We used three independent NPC lines (NSEB5-2C, NS195R, NS21) established from different ES cell lines (EB5, 195R, 21, respectively). Genes exhibiting relatively higher expression (1.5 fold) in NSEB5-2C and NS195R (or, NSEB5-2C and NS21) were selected by comparing with Mixture (consisting of equal microgram of RNAs from heart, kidney, thymus, spleen, liver, lung, d11 embryo). Gene Ontology (GO) terms ‘DNA binding’ and ‘transcription activity’ were used to select TFs.