Grupa wyszogradzka - procesy ekonomiczne i tendencje rozwojowe w ostatnich latach

Taking a look back to the last 15-20 years and making a comparison between the transition processes of the region, more or less it can be stated that the transition of the so-called Visegrád countries was successful. These countries were hit hard by the crisis created new challenges for them.W pracy przedstawiono analizę procesów ekonomicznych mających miejsce w ostatnich dwóch dekadach w krajach Grupy Wyszogrodzkiej. Zwrócono uwagę na pozytywne wyniki zmian i szanse na dalszy rozwój w przyszłości

Co-translational assembly of proteasome subunits in NOT1-containing assemblysomes

The assembly of large multimeric complexes in the crowded cytoplasm is challenging. Here we reveal a mechanism that ensures accurate production of the yeast proteasome, involving ribosome pausing and co-translational assembly of Rpt1 and Rpt2. Interaction of nascent Rpt1 and Rpt2 then lifts ribosome pausing. We show that the N-terminal disordered domain of Rpt1 is required to ensure efficient ribosome pausing and association of nascent Rpt1 protein complexes into heavy particles, wherein the nascent protein complexes escape ribosome quality control. Immunofluorescence and in situ hybridization studies indicate that Rpt1- and Rpt2-encoding messenger RNAs co-localize in these particles that contain, and are dependent on, Not1, the scaffold of the Ccr4-Not complex. We refer to these particles as Not1-containing assemblysomes, as they are smaller than and distinct from other RNA granules such as stress granules and GW- or P-bodies. Synthesis of Rpt1 with ribosome pausing and Not1-containing assemblysome induction is conserved from yeast to human cells

Phosphoinositides and Cell Polarity in the Drosophila Egg Chamber

International audiencePhosphatidylinositol phosphates (PIPs) are essential membrane components. They are localized at distinct membrane domains and recruit distinct effectors; they play an important role in the maintenance of membrane identity. They are essential for many cellular functions that include membrane trafficking, cytoskeletal organization, cell polarity and tissue morphogenesis. Cell polarity is also controlled by a set of polarity proteins, the PAR proteins, well conserved among bilaterians. These proteins are part of two dynamic networks that are engaged in a mutual negative-feedback regulation. PAR proteins control cell polarity by regulating cytoskeletal organization, asymmetric distributions of cellular components and directional transport through the cells. They share common activities with the PIPs in the control of intracellular polarity. Therefore, the analysis of potential cross talks between polarity proteins and PIPs is particularly important. The Drosophila egg chamber provides a very good model system to study the processes that control cell polarity. It includes the oocyte, a large cell in which asymmetric transport is very easy to monitor. Furthermore, the oocyte is surrounded by a follicular epithelium that allows the study of cross talks between polarity and tissue morphogenesis. This review focuses on the polarization of Drosophila egg chamber and our understanding of PIPs requirement during Drosophila oogenesis and discusses the relationship between PIPs and polarity proteins

In Vivo Dynamics of Drosophila Nuclear Envelope Components

Nuclear pore complexes (NPCs) are multisubunit protein entities embedded into the nuclear envelope (NE). Here, we examine the in vivo dynamics of the essential Drosophila nucleoporin Nup107 and several other NE-associated proteins during NE and NPCs disassembly and reassembly that take place within each mitosis. During both the rapid mitosis of syncytial embryos and the more conventional mitosis of larval neuroblasts, Nup107 is gradually released from the NE, but it remains partially confined to the nuclear (spindle) region up to late prometaphase, in contrast to nucleoporins detected by wheat germ agglutinin and lamins. We provide evidence that in all Drosophila cells, a structure derived from the NE persists throughout metaphase and early anaphase. Finally, we examined the dynamics of the spindle checkpoint proteins Mad2 and Mad1. During mitotic exit, Mad2 and Mad1 are actively imported back from the cytoplasm into the nucleus after the NE and NPCs have reformed, but they reassociate with the NE only later in G1, concomitantly with the recruitment of the basket nucleoporin Mtor (the Drosophila orthologue of vertebrate Tpr). Surprisingly, Drosophila Nup107 shows no evidence of localization to kinetochores, despite the demonstrated importance of this association in mammalian cells