The Role of NOL6 in Ribosomal Biogenesis

Abstract

NOL6 is a nucleolar protein, highly conserved throughout evolution. Previous studies on NOL6 have linked its nucleolar localization to ribosomal biogenesis. In this study, the role of murine NOL6 in ribosome biogenesis and cell cycle progression was explored. Initially, a number of tools were generated to investigate NOL6 function. This involved raising and purifying polyclonal antibodies against NOL6. Additionally, mammalian expression vectors containing the full length Nol6 a and 13 were created. The sub-nucleolar localisation of NOL6 was observed by confocal microscopy in an attempt to study the expression pattern of NOL6 within the nucleolus. Furthermore, ribosomal biogenesis studies by pulse chase analysis were carried out. In these studies, we have shown that loss of NOL6 expression by RNA interference resulted in a significant reduction of the 47/45S precursor rRNA in NIH3T3. We also found that loss of NOL6 expression within these cells resulted in G1 phase arrest and induction of cell death. These findings demonstrate a previously unknown function ofNOL6 in rRNA processing and cell cycle progression.