Search results for "regulator"
showing 10 items of 1009 documents
Hematopoietic stem cell quiescence and function are controlled by the CYLD–TRAF2–p38MAPK pathway
2015
Tesio at al. identify a novel pathway controlled by the tumor suppressor and deubiquitinase cylindromatosis (CYLD), which is involved in the regulation of hematopoietic stem cell quiescence and repopulation potential.
Binding properties and stability of the Ras-association domain of Rap1-GTP interacting adapter molecule (RIAM).
2012
The Rap1-GTP interacting adapter protein (RIAM) is an important protein in Rap1-mediated integrin activation. By binding to both Rap1 GTPase and talin, RIAM recruits talin to the cell membrane, thus facilitating talin-dependent integrin activation. In this article, we studied the role of the RIAM Ras-association (RA) and pleckstrin-homology (PH) domains in the interaction with Rap1. We found that the RA domain was sufficient for GTP-dependent interaction with Rap1B, and the addition of the PH domain did not change the binding affinity. We also detected GTP-independent interaction of Rap1B with the N-terminus of RIAM. In addition, we found that the PH domain stabilized the RA domain both in …
Chromatin modifiers and recombination factors promote a telomere fold-back structure, that is lost during replicative senescence.
2020
Telomeres have the ability to adopt a lariat conformation and hence, engage in long and short distance intra-chromosome interactions. Budding yeast telomeres were proposed to fold back into subtelomeric regions, but a robust assay to quantitatively characterize this structure has been lacking. Therefore, it is not well understood how the interactions between telomeres and non-telomeric regions are established and regulated. We employ a telomere chromosome conformation capture (Telo-3C) approach to directly analyze telomere folding and its maintenance in S. cerevisiae. We identify the histone modifiers Sir2, Sin3 and Set2 as critical regulators for telomere folding, which suggests that a dis…
The histone deacetylase Rpd3 regulates the heterochromatin structure of Drosophila telomeres
2011
Telomeres are specialized structures at the end of eukaryotic chromosomes that are required to preserve genome integrity, chromosome stability and nuclear architecture. Telomere maintenance and function are established epigenetically in several eukaryotes. However, the exact chromatin enzymatic modifications regulating telomere homeostasis are poorly understood. In Drosophila melanogaster, telomere length and stability are maintained through the retrotransposition of specialized telomeric sequences and by the specific loading of protecting capping proteins, respectively. Here, we show that the loss of the essential and evolutionarily conserved histone deacetylase Rpd3, the homolog of mammal…
Il ruolo del white paper sulle offerte al pubblico di cripto-attività alla luce della proposta MiCA
2022
La proposta MiCA, nel regolare il white paper sulle offerte di crypto-assets, sembra tenere in considerazione i benefici e i limiti dei sistemi di voluntary e di mandatory disclosure, non optando integralmente né per il primo, né per il secondo. In quest’ottica, se può condividersi l’approccio regolamentare diretto a graduare, a seconda della tipologia di token offerto, sia il contenuto che l’assoggettamento del documento a mera notifica o ad approvazione ex ante da parte dell’Autorità competente, dubbi sorgono in ordine all’indistinta allocazione dell’onere della prova in capo all’oblato, nei casi di violazione della disciplina del relativo white paper.
CONCESSIONI DEMANIALI MARITTIME E DIRITTO EUROUNITARIO: LA FINE DEL TEMPO DELLE MORE
2023
Il contributo analizza il frammentario quadro normativo delle concessioni demaniali marittime, lacuali e fluviali con finalità turistico-ricreativa alla luce degli orientamenti della giurisprudenza domestica, con le significative pronunce del Consiglio di Stato e di quella della Corte di Giustizia dell’Unione europea, in particolare della recentissima sentenza 20 aprile 2023 (C-348/22).
Tutela e sicurezza del lavoro tra centro e periferia: la sicurezza sui luoghi di lavoro
2013
Il saggio prende in esame la complessa questione del riparto di competenze tra Stato e Regioni alla luce del Titolo V della Costituzione in materia di salute e sicurezza sui luoghi di lavoro. Il riparto di competenze tra centro e periferia è stato oggetto di una limitata analisi da parte della dottrina e della giurisprudenza, che si sono concentrate in particolare sulla disciplina del mercato del lavoro. L’Autore descrive un sistema multilivello, caratterizzato dalla compresenza di fonti nazionali e regionali, della contrattazione collettiva, nonché di codici di condotta. Sulla scorta di una ricostruzione del quadro normativo e dei percorsi della giurisprudenza, il saggio propone una lettur…
No evidence for sequences structurally related to the RB1 gene in the human genome.
1991
The retinoblastoma (RB1) gene is a ubiquitously expressed gene encoding a cell-cycle control protein. Inactivation of this gene plays a crucial role in the development of retinoblastoma, osteosarcoma, and other tumors. In a search for structurally related gene sequences we identified a 5.5-kb BamHI fragment strongly cross-hybridizing with the 5′ end of the RB1 cDNA. Molecular cloning, in situ hybridization, restriction mapping, and sequence analysis identified this DNA segment as the 28S rRNA gene. The absence of other cross-hybridizing sequences suggests that the RB1 gene is not part of a structurally related gene family.
Ras, Rap, and Rac Small GTP-binding Proteins Are Targets for Clostridium sordellii Lethal Toxin Glucosylation
1996
Lethal toxin (LT) from Clostridium sordellii is one of the high molecular mass clostridial cytotoxins. On cultured cells, it causes a rounding of cell bodies and a disruption of actin stress fibers. We demonstrate that LT is a glucosyltransferase that uses UDP-Glc as a cofactor to covalently modify 21-kDa proteins both in vitro and in vivo. LT glucosylates Ras, Rap, and Rac. In Ras, threonine at position 35 was identified as the target amino acid glucosylated by LT. Other related members of the Ras GTPase superfamily, including RhoA, Cdc42, and Rab6, were not modified by LT. Incubation of serum-starved Swiss 3T3 cells with LT prevents the epidermal growth factor-induced phosphorylation of m…
Thymoma and paraneoplastic myasthenia gravis
2010
Paraneoplastic autoimmune diseases associate occasionally with small cell lung cancers and gynecologic tumors. However, myasthenia gravis (MG) occurs in at least 30% of all patients with thymomas (usually present at MG diagnosis). These epithelial neoplasms almost always have numerous admixed maturing polyclonal T cells (thymocytes). This thymopoiesis-and export of mature CD4(+)T cells-particularly associates with MG, though there are rare/puzzling exceptions in apparently pure epithelial WHO type A thymomas. Other features potentially leading to inefficient self-tolerance induction include defective epithelial expression of the autoimmune regulator (AIRE) gene and/or of major histocompatib…