Human Tumor Suppressor P14ARF Negatively Regulates Rrna Transcription Through Interacting With Transcription Factor KLF6

ARF is an important tumor suppressor, named p14ARF in human. ARF protein plays an important role in cell cycle arrest and DNA damage induced apoptosis. The nucleolar ARF protein has been shown to regulate cell cycle through both p53-dependent and p53-independent path-ways, and it can regulate cell cycle through the negative control of rRNA transcription. Kruppel-like factor 6 (KLF6) is a ubiquitously expressed member of the Kruppel-like family of transcription factors. It can play an important role in cell cycle, growth and apoptosis through regulating certain target gene.We find that Kruppel-like factor 6 protein could upregulate rRNA transcription, interact with ARF protein and coloclize with ARF in nucleolar. And ARF can negatively regulate rRNA transcription through decreasing the protein level of KLF6. We find a new negative path-way of rRNA transcription regulation, which is a significant research.