TY - JOUR TI - Nucleolar dynamics and interactions with nucleoplasm in living cells AU - Caragine, Christina M AU - Haley, Shannon C AU - Zidovska, Alexandra A2 - Weigel, Detlef A2 - Chakraborty, Arup K A2 - Pappu, Rohit V A2 - Li, Pilong VL - 8 PY - 2019 DA - 2019/11/26 SP - e47533 C1 - eLife 2019;8:e47533 DO - 10.7554/eLife.47533 UR - https://doi.org/10.7554/eLife.47533 AB - Liquid-liquid phase separation (LLPS) has been recognized as one of the key cellular organizing principles and was shown to be responsible for formation of membrane-less organelles such as nucleoli. Although nucleoli were found to behave like liquid droplets, many ramifications of LLPS including nucleolar dynamics and interactions with the surrounding liquid remain to be revealed. Here, we study the motion of human nucleoli in vivo, while monitoring the shape of the nucleolus-nucleoplasm interface. We reveal two types of nucleolar pair dynamics: an unexpected correlated motion prior to coalescence and an independent motion otherwise. This surprising kinetics leads to a nucleolar volume distribution, p⁢(V)∼V-1, unaccounted for by any current theory. Moreover, we find that nucleolus-nucleoplasm interface is maintained by ATP-dependent processes and susceptible to changes in chromatin transcription and packing. Our results extend and enrich the LLPS framework by showing the impact of the surrounding nucleoplasm on nucleoli in living cells. KW - nucleolus KW - nucleus KW - nucleoplasm KW - liquid-liquid phase separation KW - nucleolar dynamics JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -