@article{6124,
  abstract     = {Despite the importance of G-protein coupled receptors (GPCRs) their biogenesis is poorly understood. Like vertebrates, C. elegans uses a large family of GPCRs as chemoreceptors. A subset of these receptors, such as ODR-10, requires the odr-4 and odr-8 genes to be appropriately localized to sensory cilia. The odr-4 gene encodes a conserved tail-anchored transmembrane protein; the molecular identity of odr-8 is unknown. Here, we show that odr-8 encodes the C. elegans ortholog of Ufm1-specific protease 2 (UfSP2). UfSPs are cysteine proteases identified biochemically by their ability to liberate the ubiquitin-like modifier Ufm1 from its pro-form and protein conjugates. ODR-8/UfSP2 and ODR-4 are expressed in the same set of twelve chemosensory neurons, and physically interact at the ER membrane. ODR-4 also binds ODR-10, suggesting that an ODR-4/ODR-8 complex promotes GPCR folding, maturation, or export from the ER. The physical interaction between human ODR4 and UfSP2 suggests that this complex's role in GPCR biogenesis may be evolutionarily conserved. Unexpectedly, mutant versions of ODR-8/UfSP2 lacking catalytic residues required for protease activity can rescue all odr-8 mutant phenotypes tested. Moreover, deleting C. elegans ufm-1 does not alter chemoreceptor traffic to cilia, either in wild type or in odr-8 mutants. Thus, UfSP2 proteins have protease- and Ufm1-independent functions in GPCR biogenesis.},
  author       = {Chen, Changchun and Itakura, Eisuke and Weber, Katherine P. and Hegde, Ramanujan S. and de Bono, Mario},
  issn         = {1553-7404},
  journal      = {PLoS Genetics},
  number       = {3},
  publisher    = {Public Library of Science (PLoS)},
  title        = {{An ER complex of ODR-4 and ODR-8/Ufm1 specific protease 2 promotes GPCR maturation by a Ufm1-independent mechanism}},
  doi          = {10.1371/journal.pgen.1004082},
  volume       = {10},
  year         = {2014},
}

@article{6126,
  abstract     = {Aerobic animals constantly monitor and adapt to changes in O2 levels. The molecular mechanisms involved in sensing O2 are, however, incompletely understood. Previous studies showed that a hexacoordinated globin called GLB-5 tunes the dynamic range of O2-sensing neurons in natural C. elegans isolates, but is defective in the N2 lab reference strain (McGrath et al., 2009; Persson et al., 2009). GLB-5 enables a sharp behavioral switch when O2 changes between 21 and 17%. Here, we show that GLB-5 also confers rapid behavioral and cellular recovery from exposure to hypoxia. Hypoxia reconfigures O2-evoked Ca2+ responses in the URX O2 sensors, and GLB-5 enables rapid recovery of these responses upon re-oxygenation. Forward genetic screens indicate that GLB-5's effects on O2 sensing require PDL-1, the C. elegans ortholog of mammalian PrBP/PDE6δ protein. In mammals, PDE6δ regulates the traffic and activity of prenylated proteins (Zhang et al., 2004; Norton et al., 2005). PDL-1 promotes localization of GCY-33 and GCY-35, atypical soluble guanylate cyclases that act as O2 sensors, to the dendritic endings of URX and BAG neurons, where they colocalize with GLB-5. Both GCY-33 and GCY-35 are predicted to be prenylated. Dendritic localization is not essential for GCY-35 to function as an O2 sensor, but disrupting pdl-1 alters the URX neuron's O2 response properties. Functional GLB-5 can restore dendritic localization of GCY-33 in pdl-1 mutants, suggesting GCY-33 and GLB-5 are in a complex. Our data suggest GLB-5 and the soluble guanylate cyclases operate in close proximity to sculpt O2 responses.},
  author       = {Gross, E. and Soltesz, Z. and Oda, S. and Zelmanovich, V. and Abergel, Z. and de Bono, Mario},
  issn         = {0270-6474},
  journal      = {Journal of Neuroscience},
  number       = {50},
  pages        = {16726--16738},
  publisher    = {Society for Neuroscience},
  title        = {{GLOBIN-5-dependent O2 responses are regulated by PDL-1/PrBP that targets prenylated soluble guanylate cyclases to dendritic endings}},
  doi          = {10.1523/jneurosci.5368-13.2014},
  volume       = {34},
  year         = {2014},
}

@inbook{6178,
  abstract     = {Mechanically coupled cells can generate forces driving cell and tissue morphogenesis during development. Visualization and measuring of these forces is of major importance to better understand the complexity of the biomechanic processes that shape cells and tissues. Here, we describe how UV laser ablation can be utilized to quantitatively assess mechanical tension in different tissues of the developing zebrafish and in cultures of primary germ layer progenitor cells ex vivo.},
  author       = {Smutny, Michael and Behrndt, Martin and Campinho, Pedro and Ruprecht, Verena and Heisenberg, Carl-Philipp J},
  booktitle    = {Tissue Morphogenesis},
  editor       = {Nelson, Celeste},
  isbn         = {9781493911639},
  issn         = {1940-6029},
  pages        = {219--235},
  publisher    = {Springer},
  title        = {{UV laser ablation to measure cell and tissue-generated forces in the zebrafish embryo in vivo and ex vivo}},
  doi          = {10.1007/978-1-4939-1164-6_15},
  volume       = {1189},
  year         = {2014},
}

@article{6319,
  abstract     = {Nous étudions le comportement asymptotique du nombre de variétés dans une certaine classe ne satisfaisant pas le principe de Hasse. Cette étude repose sur des résultats récemmentobtenus par Colliot-Thélène.},
  author       = {Bretèche, Régis de la and Browning, Timothy D},
  issn         = {1246-7405},
  journal      = {Journal de Théorie des Nombres de Bordeaux},
  number       = {1},
  pages        = {25--44},
  publisher    = {Cellule MathDoc/CEDRAM},
  title        = {{Contre-exemples au principe de Hasse pour certains tores coflasques}},
  doi          = {10.5802/jtnb.857},
  volume       = {26},
  year         = {2014},
}

@article{6739,
  abstract     = {We explore the relationship between polar and RM codes and we describe a coding scheme which improves upon the performance of the standard polar code at practical block lengths. Our starting point is the experimental observation that RM codes have a smaller error probability than polar codes under MAP decoding. This motivates us to introduce a family of codes that “interpolates” between RM and polar codes, call this family C inter = {C α : α ∈ [0, 1j}, where C α|α=1 is the original polar code, and C α|α=0 is an RM code. Based on numerical observations, we remark that the error probability under MAP decoding is an increasing function of α. MAP decoding has in general exponential complexity, but empirically the performance of polar codes at finite block lengths is boosted by moving along the family Cinter even under low-complexity decoding schemes such as, for instance, belief propagation or successive cancellation list decoder. We demonstrate the performance gain via numerical simulations for transmission over the erasure channel as well as the Gaussian channel.},
  author       = {Mondelli, Marco and Hassani, Hamed and Urbanke, Rudiger},
  issn         = {0090-6778},
  journal      = {IEEE Transactions on Communications},
  number       = {9},
  pages        = {3084--3091},
  publisher    = {IEEE},
  title        = {{From polar to Reed-Muller codes: A technique to improve the finite-length performance}},
  doi          = {10.1109/tcomm.2014.2345069},
  volume       = {62},
  year         = {2014},
}

@inproceedings{6740,
  abstract     = {We describe coding techniques that achieve the capacity of a discrete memoryless asymmetric channel. To do so, we discuss how recent advances in coding for symmetric channels yield more efficient solutions also for the asymmetric case. In more detail, we consider three basic approaches. The first one is Gallager's scheme that concatenates a linear code with a non-linear mapper, in order to bias the input distribution. We explicitly show that both polar codes and spatially coupled codes can be employed in this scenario. Further, we derive a scaling law between the gap to capacity, the cardinality of channel input and output alphabets, and the required size of the mapper. The second one is an integrated approach in which the coding scheme is used both for source coding, in order to create codewords with the capacity-achieving distribution, and for channel coding, in order to provide error protection. Such a technique has been recently introduced by Honda and Yamamoto in the context of polar codes, and we show how to apply it also to the design of sparse graph codes. The third approach is based on an idea due to Böcherer and Mathar and separates completely the two tasks of source coding and channel coding by “chaining” together several codewords. We prove that we can combine any suitable source code with any suitable channel code in order to provide optimal schemes for asymmetric channels. In particular, polar codes and spatially coupled codes fulfill the required conditions.},
  author       = {Mondelli, Marco and Urbanke, Rudiger and Hassani, Hamed},
  booktitle    = {52nd Annual Allerton Conference on Communication, Control, and Computing},
  location     = {Monticello, IL, United States},
  pages        = {789--796},
  publisher    = {IEEE},
  title        = {{How to achieve the capacity of asymmetric channels}},
  doi          = {10.1109/allerton.2014.7028535},
  year         = {2014},
}

@article{6744,
  abstract     = {With the aim of extending the coverage and improving the performance of impulse radio ultra-wideband (UWB) systems, this paper focuses on developing a novel single differential encoded decode and forward (DF) non-cooperative relaying scheme (NCR). To favor simple receiver structures, differential noncoherent detection is employed which enables effective energy capture without any channel estimation. Putting emphasis on the general case of multi-hop relaying, we illustrate an original algorithm for the joint power allocation and path selection (JPAPS), minimizing an approximate expression of the overall bit error rate (BER). In particular, after deriving a closed-form power allocation strategy, the optimal path selection is reduced to a shortest path problem on a connected graph, which can be solved without any topology information with complexity O(N 3 ), N being the number of available relays of the network. An approximate scheme is also presented, which reduces the complexity to O(N 2 ) while showing a negligible performance loss, and for benchmarking purposes, an exhaustive-search based multi-hop DF cooperative strategy is derived. Simulation results for various network setups corroborate the effectiveness of the proposed low-complexity JPAPS algorithm, which favorably compares to existing AF and DF relaying methods.},
  author       = {Mondelli, Marco and Zhou, Qi and Lottici, Vincenzo and Ma, Xiaoli},
  journal      = {IEEE Transactions on Wireless Communications},
  number       = {3},
  pages        = {1397--1409},
  publisher    = {IEEE},
  title        = {{Joint power allocation and path selection for multi-hop noncoherent decode and forward UWB communications}},
  doi          = {10.1109/twc.2014.020914.130669},
  volume       = {13},
  year         = {2014},
}

@book{6853,
  abstract     = {This monograph presents a short course in computational geometry and topology. In the first part the book covers Voronoi diagrams and Delaunay triangulations, then it presents the theory of alpha complexes which play a crucial role in biology. The central part of the book is the homology theory and their computation, including the theory of persistence which is indispensable for applications, e.g. shape reconstruction. The target audience comprises researchers and practitioners in mathematics, biology, neuroscience and computer science, but the book may also be beneficial to graduate students of these fields.},
  author       = {Edelsbrunner, Herbert},
  isbn         = {9-783-3190-5956-3},
  issn         = {2191-5318},
  pages        = {IX, 110},
  publisher    = {Springer Nature},
  title        = {{A Short Course in Computational Geometry and Topology}},
  doi          = {10.1007/978-3-319-05957-0},
  year         = {2014},
}

@techreport{7038,
  author       = {Huszár, Kristóf and Rolinek, Michal},
  pages        = {5},
  publisher    = {IST Austria},
  title        = {{Playful Math - An introduction to mathematical games}},
  year         = {2014},
}

@article{7071,
  abstract     = {Spin and orbital quantum numbers play a key role in the physics of Mott insulators, but in most systems they are connected only indirectly—via the Pauli exclusion principle and the Coulomb interaction. Iridium-based oxides (iridates) introduce strong spin–orbit coupling directly, such that these numbers become entwined together and the Mott physics attains a strong orbital character. In the layered honeycomb iridates this is thought to generate highly spin–anisotropic magnetic interactions, coupling the spin to a given spatial direction of exchange and leading to strongly frustrated magnetism. Here we report a new iridate structure that has the same local connectivity as the layered honeycomb and exhibits striking evidence for highly spin–anisotropic exchange. The basic structural units of this material suggest that a new family of three-dimensional structures could exist, the ‘harmonic honeycomb’ iridates, of which the present compound is the first example.},
  author       = {Modic, Kimberly A and Smidt, Tess E. and Kimchi, Itamar and Breznay, Nicholas P. and Biffin, Alun and Choi, Sungkyun and Johnson, Roger D. and Coldea, Radu and Watkins-Curry, Pilanda and McCandless, Gregory T. and Chan, Julia Y. and Gandara, Felipe and Islam, Z. and Vishwanath, Ashvin and Shekhter, Arkady and McDonald, Ross D. and Analytis, James G.},
  issn         = {2041-1723},
  journal      = {Nature Communications},
  publisher    = {Springer Science and Business Media LLC},
  title        = {{Realization of a three-dimensional spin–anisotropic harmonic honeycomb iridate}},
  doi          = {10.1038/ncomms5203},
  volume       = {5},
  year         = {2014},
}

@article{7072,
  abstract     = {We investigate the structural and magnetic properties of two molecule-based magnets synthesized from the same starting components. Their different structural motifs promote contrasting exchange pathways and consequently lead to markedly different magnetic ground states. Through examination of their structural and magnetic properties we show that [Cu(pyz)(H2O)(gly)2](ClO4)2 may be considered a quasi-one-dimensional quantum Heisenberg antiferromagnet whereas the related compound [Cu(pyz)(gly)](ClO4), which is formed from dimers of antiferromagnetically interacting Cu2+ spins, remains disordered down to at least 0.03 K in zero field but shows a field-temperature phase diagram reminiscent of that seen in materials showing a Bose-Einstein condensation of magnons.},
  author       = {Lancaster, T. and Goddard, P. A. and Blundell, S. J. and Foronda, F. R. and Ghannadzadeh, S. and Möller, J. S. and Baker, P. J. and Pratt, F. L. and Baines, C. and Huang, L. and Wosnitza, J. and McDonald, R. D. and Modic, Kimberly A and Singleton, J. and Topping, C. V. and Beale, T. A. W. and Xiao, F. and Schlueter, J. A. and Barton, A. M. and Cabrera, R. D. and Carreiro, K. E. and Tran, H. E. and Manson, J. L.},
  issn         = {1079-7114},
  journal      = {Physical Review Letters},
  number       = {20},
  publisher    = {APS},
  title        = {{Controlling magnetic order and quantum disorder in molecule-based magnets}},
  doi          = {10.1103/physrevlett.112.207201},
  volume       = {112},
  year         = {2014},
}

@article{10382,
  abstract     = {Protein oligomers have been implicated as toxic agents in a wide range of amyloid-related diseases. However, it has remained unsolved whether the oligomers are a necessary step in the formation of amyloid fibrils or just a dangerous byproduct. Analogously, it has not been resolved if the amyloid nucleation process is a classical one-step nucleation process or a two-step process involving prenucleation clusters. We use coarse-grained computer simulations to study the effect of nonspecific attractions between peptides on the primary nucleation process underlying amyloid fibrillization. We find that, for peptides that do not attract, the classical one-step nucleation mechanism is possible but only at nonphysiologically high peptide concentrations. At low peptide concentrations, which mimic the physiologically relevant regime, attractive interpeptide interactions are essential for fibril formation. Nucleation then inevitably takes place through a two-step mechanism involving prefibrillar oligomers. We show that oligomers not only help peptides meet each other but also, create an environment that facilitates the conversion of monomers into the β-sheet–rich form characteristic of fibrils. Nucleation typically does not proceed through the most prevalent oligomers but through an oligomer size that is only observed in rare fluctuations, which is why such aggregates might be hard to capture experimentally. Finally, we find that the nucleation of amyloid fibrils cannot be described by classical nucleation theory: in the two-step mechanism, the critical nucleus size increases with increases in both concentration and interpeptide interactions, which is in direct contrast with predictions from classical nucleation theory.},
  author       = {Šarić, Anđela and Chebaro, Yassmine C. and Knowles, Tuomas P. J. and Frenkel, Daan},
  issn         = {1091-6490},
  journal      = {Proceedings of the National Academy of Sciences},
  keywords     = {multidisciplinary},
  number       = {50},
  pages        = {17869--17874},
  publisher    = {National Academy of Sciences},
  title        = {{Crucial role of nonspecific interactions in amyloid nucleation}},
  doi          = {10.1073/pnas.1410159111},
  volume       = {111},
  year         = {2014},
}

@article{10383,
  abstract     = {We use numerical simulations to compute the equation of state of a suspension of spherical self-propelled nanoparticles in two and three dimensions. We study in detail the effect of excluded volume interactions and confinement as a function of the system's temperature, concentration, and strength of the propulsion. We find a striking nonmonotonic dependence of the pressure on the temperature and provide simple scaling arguments to predict and explain the occurrence of such anomalous behavior. We explicitly show how our results have important implications for the effective forces on passive components suspended in a bath of active particles.},
  author       = {Mallory, S. A. and Šarić, Anđela and Valeriani, C. and Cacciuto, A.},
  issn         = {1550-2376},
  journal      = {Physical Review E},
  number       = {5},
  publisher    = {American Physical Society},
  title        = {{Anomalous thermomechanical properties of a self-propelled colloidal fluid}},
  doi          = {10.1103/physreve.89.052303},
  volume       = {89},
  year         = {2014},
}

@article{1058,
  abstract     = {Diffraction-unlimited far-field super-resolution fluorescence (nanoscopy) methods typically rely on transiently transferring fluorophores between two states, whereby this transfer is usually laid out as a switch. However, depending on whether this is induced in a spatially controlled manner using a pattern of light (coordinate-targeted) or stochastically on a single-molecule basis, specific requirements on the fluorophores are imposed. Therefore, the fluorophores are usually utilized just for one class of methods only. In this study we demonstrate that the reversibly switchable fluorescent protein Dreiklang enables live-cell recordings in both spatially controlled and stochastic modes. We show that the Dreiklang chromophore entails three different light-induced switching mechanisms, namely a reversible photochemical one, off-switching by stimulated emission, and a reversible transfer to a long-lived dark state from the S1 state, all of which can be utilized to overcome the diffraction barrier. We also find that for the single-molecule- based stochastic GSDIM approach (ground-state depletion followed by individual molecule return), Dreiklang provides a larger number of on-off localization events as compared to its progenitor Citrine. Altogether, Dreiklang is a versatile probe for essentially all popular forms of live-cell fluorescence nanoscopy.},
  author       = {Jensen, Nickels and Danzl, Johann G and Willig, Katrin and Lavoie Cardinal, Flavie and Brakemann, Tanja and Hell, Stefan and Jakobs, Stefan},
  journal      = {ChemPhysChem},
  number       = {4},
  pages        = {756 -- 762},
  publisher    = {Wiley-Blackwell},
  title        = {{Coordinate-targeted and coordinate-stochastic super-resolution microscopy with the reversibly switchable fluorescent protein dreiklang}},
  doi          = {10.1002/cphc.201301034},
  volume       = {15},
  year         = {2014},
}

@inproceedings{10793,
  abstract     = {The Hanani–Tutte theorem is a classical result proved for the first time in the 1930s that characterizes planar graphs as graphs that admit a drawing in the plane in which every pair of edges not sharing a vertex cross an even number of times. We generalize this classical result to clustered graphs with two disjoint clusters, and show that a straightforward extension of our result to flat clustered graphs with three or more disjoint clusters is not possible.

We also give a new and short proof for a related result by Di Battista and Frati based on the matroid intersection algorithm.},
  author       = {Fulek, Radoslav and Kynčl, Jan and Malinović, Igor and Pálvölgyi, Dömötör},
  booktitle    = {International Symposium on Graph Drawing},
  issn         = {0302-9743},
  pages        = {428--436},
  publisher    = {Springer Nature},
  title        = {{Clustered planarity testing revisited}},
  doi          = {10.1007/978-3-662-45803-7_36},
  volume       = {8871},
  year         = {2014},
}

@book{10811,
  abstract     = {Auxin is an important signaling compound in plants and vital for plant development and growth. The present book, Auxin and its Role in Plant Development, provides the reader with detailed and comprehensive insight into the functioning of the molecule on the whole and specifically in plant development. In the first part, the functioning, metabolism and signaling pathways of auxin in plants are explained, the second part depicts the specific role of auxin in plant development and the third part describes the interaction and functioning of the signaling compound  upon stimuli of the environment. Each chapter is written by international experts in the respective field and designed for scientists and researchers in plant biology, plant development and cell biology to summarize the recent progress in understanding the role of auxin and suggest future perspectives for auxin research.},
  editor       = {Zažímalová, Eva and Petrášek, Jan and Benková, Eva},
  isbn         = {9783709115251},
  pages        = {444},
  publisher    = {Springer Nature},
  title        = {{Auxin and Its Role in Plant Development}},
  doi          = {10.1007/978-3-7091-1526-8},
  year         = {2014},
}

@article{10814,
  abstract     = {We review recent progress towards a rigorous understanding of the excitation spectrum of bosonic quantum many-body systems. In particular, we explain how one can rigorously establish the predictions resulting from the Bogoliubov approximation in the mean field limit. The latter predicts that the spectrum is made up of elementary excitations, whose energy behaves linearly in the momentum for small momentum. This property is crucial for the superfluid behavior of the system. We also discuss a list of open problems in this field.},
  author       = {Seiringer, Robert},
  issn         = {1869-7135},
  journal      = {Jahresbericht der Deutschen Mathematiker-Vereinigung},
  keywords     = {General Medicine},
  pages        = {21--41},
  publisher    = {Springer Nature},
  title        = {{The excitation spectrum for Bose fluids with weak interactions}},
  doi          = {10.1365/s13291-014-0083-9},
  volume       = {116},
  year         = {2014},
}

@article{10815,
  abstract     = {In the last several decades, developmental biology has clarified the molecular mechanisms of embryogenesis and organogenesis. In particular, it has demonstrated that the “tool-kit genes” essential for regulating developmental processes are not only highly conserved among species, but are also used as systems at various times and places in an organism to control distinct developmental events. Therefore, mutations in many of these tool-kit genes may cause congenital diseases involving morphological abnormalities. This link between genes and abnormal morphological phenotypes underscores the importance of understanding how cells behave and contribute to morphogenesis as a result of gene function. Recent improvements in live imaging and in quantitative analyses of cellular dynamics will advance our understanding of the cellular pathogenesis of congenital diseases associated with aberrant morphologies. In these studies, it is critical to select an appropriate model organism for the particular phenomenon of interest.},
  author       = {Hashimoto, Masakazu and Morita, Hitoshi and Ueno, Naoto},
  issn         = {0914-3505},
  journal      = {Congenital Anomalies},
  keywords     = {Developmental Biology, Embryology, General Medicine, Pediatrics, Perinatology, and Child Health},
  number       = {1},
  pages        = {1--7},
  publisher    = {Wiley},
  title        = {{Molecular and cellular mechanisms of development underlying congenital diseases}},
  doi          = {10.1111/cga.12039},
  volume       = {54},
  year         = {2014},
}

@article{9458,
  abstract     = {Dnmt1 epigenetically propagates symmetrical CG methylation in many eukaryotes. Their genomes are typically depleted of CG dinucleotides because of imperfect repair of deaminated methylcytosines. Here, we extensively survey diverse species lacking Dnmt1 and show that, surprisingly, symmetrical CG methylation is nonetheless frequently present and catalyzed by a different DNA methyltransferase family, Dnmt5. Numerous Dnmt5-containing organisms that diverged more than a billion years ago exhibit clustered methylation, specifically in nucleosome linkers. Clustered methylation occurs at unprecedented densities and directly disfavors nucleosomes, contributing to nucleosome positioning between clusters. Dense methylation is enabled by a regime of genomic sequence evolution that enriches CG dinucleotides and drives the highest CG frequencies known. Species with linker methylation have small, transcriptionally active nuclei that approach the physical limits of chromatin compaction. These features constitute a previously unappreciated genome architecture, in which dense methylation influences nucleosome positions, likely facilitating nuclear processes under extreme spatial constraints.},
  author       = {Huff, Jason T. and Zilberman, Daniel},
  issn         = {1097-4172},
  journal      = {Cell},
  number       = {6},
  pages        = {1286--1297},
  publisher    = {Elsevier},
  title        = {{Dnmt1-independent CG methylation contributes to nucleosome positioning in diverse eukaryotes}},
  doi          = {10.1016/j.cell.2014.01.029},
  volume       = {156},
  year         = {2014},
}

@article{9479,
  abstract     = {Centromeres mediate chromosome segregation and are defined by the centromere-specific histone H3 variant (CenH3)/centromere protein A (CENP-A). Removal of CenH3 from centromeres is a general property of terminally differentiated cells, and the persistence of CenH3 increases the risk of diseases such as cancer. However, active mechanisms of centromere disassembly are unknown. Nondividing Arabidopsis pollen vegetative cells, which transport engulfed sperm by extended tip growth, undergo loss of CenH3; centromeric heterochromatin decondensation; and bulk activation of silent rRNA genes, accompanied by their translocation into the nucleolus. Here, we show that these processes are blocked by mutations in the evolutionarily conserved AAA-ATPase molecular chaperone, CDC48A, homologous to yeast Cdc48 and human p97 proteins, both of which are implicated in ubiquitin/small ubiquitin-like modifier (SUMO)-targeted protein degradation. We demonstrate that CDC48A physically associates with its heterodimeric cofactor UFD1-NPL4, known to bind ubiquitin and SUMO, as well as with SUMO1-modified CenH3 and mutations in NPL4 phenocopy cdc48a mutations. In WT vegetative cell nuclei, genetically unlinked ribosomal DNA (rDNA) loci are uniquely clustered together within the nucleolus and all major rRNA gene variants, including those rDNA variants silenced in leaves, are transcribed. In cdc48a mutant vegetative cell nuclei, however, these rDNA loci frequently colocalized with condensed centromeric heterochromatin at the external periphery of the nucleolus. Our results indicate that the CDC48ANPL4 complex actively removes sumoylated CenH3 from centromeres and disrupts centromeric heterochromatin to release bulk rRNA genes into the nucleolus for ribosome production, which fuels single nucleus-driven pollen tube growth and is essential for plant reproduction.},
  author       = {Mérai, Zsuzsanna and Chumak, Nina and García-Aguilar, Marcelina and Hsieh, Tzung-Fu and Nishimura, Toshiro and Schoft, Vera K. and Bindics, János and Ślusarz, Lucyna and Arnoux, Stéphanie and Opravil, Susanne and Mechtler, Karl and Zilberman, Daniel and Fischer, Robert L. and Tamaru, Hisashi},
  issn         = {1091-6490},
  journal      = {Proceedings of the National Academy of Sciences},
  number       = {45},
  pages        = {16166--16171},
  publisher    = {National Academy of Sciences},
  title        = {{The AAA-ATPase molecular chaperone Cdc48/p97 disassembles sumoylated centromeres, decondenses heterochromatin, and activates ribosomal RNA genes}},
  doi          = {10.1073/pnas.1418564111},
  volume       = {111},
  year         = {2014},
}

