Ikaros encodes a zinc finger protein that is involved in gene regulation and chromatin remodeling. The majority of Ikaros localizes at pericentromeric heterochromatin (PC-HC) where it regulates expression of target genes. Ikaros function is controlled by posttranslational modification. Phosphorylation of Ikaros by CK2 kinase determines its ability to bind DNA and exert cell cycle control as well as its subcellular localization. We report that Ikaros interacts with protein phosphatase 1 (PP1) via a conserved PP1 binding motif, RVXF, in the C-terminal end of the Ikaros protein. Point mutations of the RVXF motif abolish Ikaros-PP1 interaction and result in decreased DNA binding, an inability to localize to PC-HC, and rapid degradation of the Ikaros protein. The introduction of alanine mutations at CK2-phosphorylated residues increases the half-life of the PP1-nonbinding Ikaros mutant. This suggests that dephosphorylation of these sites by PP1 stabilizes the Ikaros protein and prevents its degradation. In the nucleus, Ikaros forms complexes with ubiquitin, providing evidence that Ikaros degradation involves the ubiquitin/proteasome pathway. In vivo, Ikaros can target PP1 to the nucleus, and a fraction of PP1 colocalizes with Ikaros at PC-HC. These data suggest a novel function for the Ikaros protein; that is, the targeting of PP1 to PC-HC and other chromatin structures. We propose a model whereby the function of Ikaros is controlled by the CK2 and PP1 pathways and that a balance between these two signal transduction pathways is essential for normal cellular function and for the prevention of malignant transformation.

The aim of this paper is to extend from manifolds to vector bundles some classical geometric objects, associated with Lagrange and Hamilton metrics. Considering vector bundles endowed with almost Lie structures, defined in [24] by one of the authors, some geometric objects like R-(semi)sprays and R-connections of Cartan type are defined and studied. It is proved that the Lagrange equations deduced for Lie algebroids by A. Weinstein have a similar form for almost Lie structures.

Affine Hamiltonians are defined in the paper and their study is based especially on the fact that in the hyperregular case they are dual objects of Lagrangians defined on affine bundles, by mean of natural Legendre maps. The variational problems for affine Hamiltonians and Lagrangians of order k ≥ 2 are studied, relating them to a Hamilton equation. An Ostrogradski type theorem is proved: the Hamilton equation of an affine Hamiltonian h is equivalent with Euler-Lagrange equation of its dual Lagrangian L. Zermelo condition is also studied and some non-trivial examples are given.

Sports organizations worldwide are discovering their power of influence over the fans and communities in which they operate, making more and more specialists and practitioners question these organizations’ social responsibility and sustainable development. In sports organizations, although research is increasing, social responsibility and sustainability are topics that require special attention because sports organizations can instill values in a large number of people in different fields. In our paper, we propose a conceptual framework that allows for integrated research into corporate social responsibility (CSR) and the sustainability of sports organizations for sustainable management and identifies their influences on the overall performance. Based on the conceptual framework, we developed a scale for measuring sports organizations’ social responsibility and sustainability, which we applied within sports organizations in Romania. The empirical study involved 280 respondents selected from the first two leagues of four sports areas (football, handball, volleyball, basketball). To support the conceptual framework, we used quantitative research methods in a transversal analysis: structural equation modeling and artificial neural network analysis. The conclusions of the empirical study in Romania show that social responsibility and sustainability are essential for the sustainable management of sports organizations and significantly influence the organization’s overall performance. Among the pillars of sustainability, the social and human impact performance, given the specifics of sports organizations (involving large masses of people). Furthermore, legal and philanthropic responsibilities significantly influence CSR and organizational performance among CSR responsibilities.

The derived generalized algebroid and the derived generalized Lie algebroid of an anchored vector bundle are defined. Some natural functors from the two categories of anchored vector bundles to the corresponding categories of generalized algebroids and generalized Lie algebroids respectively are also considered. A natural result is proved: the derived (Lie) algebroid of an anchored vector subbundle is a generalized (Lie) algebroid of the underlying bundle. Lifts of linear R-connections and skewsymmetric forms respectively are constructed and the modular class of an almost Lie structure is defined.