KDM2B/FBXL10 targets c-Fos for ubiquitylation and degradation in response to mitogenic stimulation.

KDM2B (also known as FBXL10) controls stem cell self-renewal, somatic cell reprogramming and senescence, and tumorigenesis. KDM2B contains multiple functional domains, including a JmjC domain that catalyzes H3K36 demethylation and a CxxC zinc-finger that recognizes CpG islands and recruits the polycomb repressive complex 1. Here, we report that KDM2B, via its F-box domain, functions as a subunit of the CUL1-RING ubiquitin ligase (CRL1/SCF(KDM2B)) complex. KDM2B targets c-Fos for polyubiquitylation and regulates c-Fos protein levels. Unlike the phosphorylation of other SCF (SKP1-CUL1-F-box)/CRL1 substrates that promotes substrates binding to F-box, epidermal growth factor (EGF)-induced c-Fos S374 phosphorylation dissociates c-Fos from KDM2B and stabilizes c-Fos protein. Non-phosphorylatable and phosphomimetic mutations at S374 result in c-Fos protein which cannot be induced by EGF or accumulates constitutively and lead to decreased or increased cell proliferation, respectively. Multiple tumor-derived KDM2B mutations impaired the function of KDM2B to target c-Fos degradation and to suppress cell proliferation. These results reveal a novel function of KDM2B in the negative regulation of cell proliferation by assembling an E3 ligase to targeting c-Fos protein degradation that is antagonized by mitogenic stimulations

Two-dimensional Superconductivity from Dimerization of Atomically Ordered AuTe2Se4/3 Cubes

The emergent phenomena such as superconductivity and topological phase transitions can be observed in strict two-dimensional crystalline matters. Artificial interfaces and one atomic thickness layers are typical 2D materials of this kind. Although having 2D characters, most bulky layered compounds, however, do not possess these striking properties. Here, we report the 2D superconductivity in bulky AuTe2Se4/3,where the reduction in dimensionality is achieved through inducing the elongated covalent Te-Te bonds. The atomic-resolution images reveal that the Au, Te and Se are atomically ordered in a cube, among which are Te-Te bonds of 3.18 A and 3.28 A. The superconductivity at 2.85 K is discovered, which is unraveled to be the quasi-2D nature owing to the BKT topological transition. The nesting of nearly parallel Fermi sheets could give rise to strong electron-phonon coupling. It is proposed to further depleting the thickness could result in more topologically-related phenomena.Comment: 16 pages, 5 figures,To be published in Nature Communication

Thermodynamic analysis of BN, AlN AND TiN Precipitation in boron-bearing steel

In this paper, the precipitation behavior of BN, AlN and TiN particles in boron-bearing steel was studied based on thermodynamic calculation. During solidification process, precipitation amount of BN has a positive relationship with boron content, while has negative relationship with temperature. The binding capacity of boron and nitrogen is greater than that of aluminum and nitrogen, BN is preferentially precipitated as boron added to steel. BN particle reduces the free nitrogen content in steel and then prevents the formation of AlN particle. Combination of titanium and nitrogen element is more precedence than of boron and nitrogen element. Formation of TiN particle precedes BN particle, and the precipitation amount of BN is significantly reduced by adding titanium element to boronbearing

Thermodynamic analysis of BN, AlN AND TiN Precipitation in boron-bearing steel

In this paper, the precipitation behavior of BN, AlN and TiN particles in boron-bearing steel was studied based on thermodynamic calculation. During solidification process, precipitation amount of BN has a positive relationship with boron content, while has negative relationship with temperature. The binding capacity of boron and nitrogen is greater than that of aluminum and nitrogen, BN is preferentially precipitated as boron added to steel. BN particle reduces the free nitrogen content in steel and then prevents the formation of AlN particle. Combination of titanium and nitrogen element is more precedence than of boron and nitrogen element. Formation of TiN particle precedes BN particle, and the precipitation amount of BN is significantly reduced by adding titanium element to boronbearing

Ground-State Fidelity and Kosterlitz-Thouless Phase Transition for Spin 1/2 Heisenberg Chain with Next-to-the-Nearest-Neighbor Interaction

The Kosterlitz-Thouless transition for the spin 1/2 Heisenberg chain with the next-to-the-nearest-neighbor interaction is investigated in the context of an infinite matrix product state algorithm, which is a generalization of the infinite time-evolving block decimation algorithm [G. Vidal, Phys. Rev. Lett. \textbf{98}, 070201 (2007)] to accommodate both the next-to-the-nearest-neighbor interaction and spontaneous dimerization. It is found that, in the critical regime, the algorithm automatically leads to infinite degenerate ground-state wave functions, due to the finiteness of the truncation dimension. This results in \textit{pseudo} symmetry spontaneous breakdown, as reflected in a bifurcation in the ground-state fidelity per lattice site. In addition, this allows to introduce a pseudo-order parameter to characterize the Kosterlitz-Thouless transition.Comment: 4 pages, 4 figure