TY - JOUR AB - We perform precision measurements on a Mott-insulator quantum state of ultracold atoms with tunable interactions. We probe the dependence of the superfluid-to-Mott-insulator transition on the interaction strength and explore the limits of the standard Bose-Hubbard model description. By tuning the on-site interaction energies to values comparable to the interband separation, we are able to quantitatively measure number-dependent shifts in the excitation spectrum caused by effective multibody interactions. AU - Mark, Manfred AU - Haller, Elmar AU - Lauber, Katharina AU - Danzl, Johann G AU - Daley, Andrew AU - Nägerl, Hanns ID - 1053 IS - 17 JF - Physical Review Letters TI - Precision measurements on a tunable Mott insulator of ultracold atoms VL - 107 ER - TY - JOUR AB - We investigate local three-body correlations for bosonic particles in three dimensions and one dimension as a function of the interaction strength. The three-body correlation function g(3) is determined by measuring the three-body recombination rate in an ultracold gas of Cs atoms. In three dimensions, we measure the dependence of g(3) on the gas parameter in a BEC, finding good agreement with the theoretical prediction accounting for beyond-mean-field effects. In one dimension, we observe a reduction of g( 3) by several orders of magnitude upon increasing interactions from the weakly interacting BEC to the strongly interacting Tonks-Girardeau regime, in good agreement with predictions from the Lieb-Liniger model for all strengths of interaction. AU - Haller, Elmar AU - Rabie, Mahmoud AU - Mark, Manfred AU - Danzl, Johann G AU - Hart, Russell AU - Lauber, Katharina AU - Pupillo, Guido AU - Nägerl, Hanns ID - 1054 IS - 23 JF - Physical Review Letters TI - Three-body correlation functions and recombination rates for bosons in three dimensions and one dimension VL - 107 ER - TY - JOUR AB - Nuclear pore complexes (NPCs) assemble at the end of mitosis during nuclear envelope (NE) reformation and into an intact NE as cells progress through interphase. Although recent studies have shown that NPC formation occurs by two different molecular mechanisms at two distinct cell cycle stages, little is known about the molecular players that mediate the fusion of the outer and inner nuclear membranes to form pores. In this paper, we provide evidence that the transmembrane nucleoporin (Nup), POM121, but not the Nup107–160 complex, is present at new pore assembly sites at a time that coincides with inner nuclear membrane (INM) and outer nuclear membrane (ONM) fusion. Overexpression of POM121 resulted in juxtaposition of the INM and ONM. Additionally, Sun1, an INM protein that is known to interact with the cytoskeleton, was specifically required for interphase assembly and localized with POM121 at forming pores. We propose a model in which POM121 and Sun1 interact transiently to promote early steps of interphase NPC assembly. AU - Talamas, Jessica A. AU - HETZER, Martin W ID - 11094 IS - 1 JF - Journal of Cell Biology KW - Cell Biology SN - 0021-9525 TI - POM121 and Sun1 play a role in early steps of interphase NPC assembly VL - 194 ER - TY - JOUR AB - As the gatekeepers of the eukaryotic cell nucleus, nuclear pore complexes (NPCs) mediate all molecular trafficking between the nucleoplasm and the cytoplasm. In recent years, transport-independent functions of NPC components, nucleoporins, have been identified including roles in chromatin organization and gene regulation. Here, we summarize our current view of the NPC as a dynamic hub for the integration of chromatin regulation and nuclear trafficking and discuss the functional interplay between nucleoporins and the nuclear genome. AU - Liang, Yun AU - HETZER, Martin W ID - 11096 IS - 1 JF - Current Opinion in Cell Biology KW - Cell Biology SN - 0955-0674 TI - Functional interactions between nucleoporins and chromatin VL - 23 ER - TY - JOUR AU - HETZER, Martin W AU - Cavalli, Giacomo ID - 11095 IS - 3 JF - Current Opinion in Cell Biology KW - Cell Biology SN - 0955-0674 TI - Editorial overview VL - 23 ER -