tokens: Transient , high-level Ras expression induces transcriptional activation of p21 mediated by a GC rich region in p21 promoter -83 -54 bp relative to the transcription initiation site containing binding sites for Sp1 family transcription factors .
folded_tokens: transient , high-level ra expression induce transcriptional activation of p21 mediate by a gc rich region in p21 promoter -83 -54 bp relative to the transcription initiation site contain binding site for sp1 family transcription factor .