Search results for "Repressor"
showing 10 items of 212 documents
Electroclinical features and outcome of ANKRD11-related KBG syndrome: A novel report and literature review.
2021
KBG syndrome (OMIM #148050) is a rare autosomal dominant disorder, typically characterized by macrodontia of the upper central incisors, distinct craniofacial findings, short stature, and skeletal anomalies associated with neurological involvement including intellectual disability, behaviour difficulties, and epilepsy. KBG syndrome is associated with mutations in ANKRD11 gene that plays a chromatin regulator role of histone acetylation and gene expression during neurogenesis in the embryonic brain.
Symmetry Breaking and Establishment of Dorsal/Ventral Polarity in the Early Sea Urchin Embryo
2015
The mechanisms imposing the Dorsal/Ventral (DV) polarity of the early sea urchin embryo consist of a combination of inherited maternal information and inductive interactions among blastomeres. Old and recent studies suggest that a key molecular landmark of DV polarization is the expression of nodal on the future ventral side, in apparent contrast with other metazoan embryos, where nodal is expressed dorsally. A subtle maternally-inherited redox anisotropy, plus some maternal factors such as SoxB1, Univin, and p38-MAPK have been identified as inputs driving the spatially asymmetric transcription of nodal. However, all the mentioned factors are broadly distributed in the embryo as early as no…
Polycomb-like 2 Associates with PRC2 and Regulates Transcriptional Networks during Mouse Embryonic Stem Cell Self-Renewal and Differentiation
2010
SummaryPolycomb group (PcG) proteins are conserved epigenetic transcriptional repressors that control numerous developmental gene expression programs and have recently been implicated in modulating embryonic stem cell (ESC) fate. We identified the PcG protein PCL2 (polycomb-like 2) in a genome-wide screen for regulators of self-renewal and pluripotency and predicted that it would play an important role in mouse ESC-fate determination. Using multiple biochemical strategies, we provide evidence that PCL2 is a Polycomb Repressive Complex 2 (PRC2)-associated protein in mouse ESCs. Knockdown of Pcl2 in ESCs resulted in heightened self-renewal characteristics, defects in differentiation, and alte…
Establishment of Polycomb silencing requires a transient interaction between PC and ESC
2001
Two distinct types of Polycomb complexes have been identified in flies and in vertebrates, one containing ESC and one containing PC. Using LexA fusions, we show that PC and ESC can establish silencing of a reporter gene but that each requires the presence of the other. In early embryonic extracts, we find PC transiently associated with ESC in a complex that includes EZ, PHO, PH, GAGA, and RPD3 but not PSC. In older embryos, PC is found in a complex including PH, PSC, GAGA, and RPD3, whereas ESC is in a separate complex including EZ, PHO, and RPD3.
FKBP51 Affects TNF-Related Apoptosis Inducing Ligand Response in Melanoma
2021
Melanoma is one of the most immunogenic tumors and has the highest potential to elicit specific adaptive antitumor immune responses. Immune cells induce apoptosis of cancer cells either by soluble factors or by triggering cell-death pathways. Melanoma cells exploit multiple mechanisms to escape immune system tumoricidal control. FKBP51 is a relevant pro-oncogenic factor of melanoma cells supporting NF-κB-mediated resistance and cancer stemness/invasion epigenetic programs. Herein, we show that FKBP51-silencing increases TNF-related apoptosis-inducing ligand (TRAIL)-R2 (DR5) expression and sensitizes melanoma cells to TRAIL-induced apoptosis. Consistent with the general increase in histone d…
Prohibitin, an essential protein for Colorado potato beetle larval viability, is relevant to Bacillus thuringiensis Cry3Aa toxicity
2013
Bacillus thuringienesis (Bt) Cry toxins constitute the most extensively used environmentally safe biopesticide and their mode of action relies on the interaction of the toxins with membrane proteins in the midgut of susceptible insects that mediate toxicity and insect specificity. Therefore, identification of Bt Cry toxin interacting proteins in the midgut of target insects and understanding their role in toxicity is of great interest to exploit their insecticidal action. Using ligand blot, we demonstrated that Bt Cry3Aa toxin bound to a 30kDa protein in Colorado potato beetle (CPB) larval midgut membrane, identified by sequence homology as prohibitin-1 protein. Prohibitins comprise a highl…
SUMOylation of Blimp-1 promotes its proteasomal degradation
2011
Abstract B lymphocyte induced maturation protein-1 (Blimp-1) is a transcription repressor of the Krueppel-like family. Blimp-1 plays important roles in developmental processes, such as of germ cells and hair follicle stem cells. In B lymphocytes Blimp-1 orchestrates the terminal differentiation into plasma cells. We discovered that Blimp-1 undergoes SUMOylation by SUMO-1. This SUMOylation is modulated by the SUMO protease SENP1. While Blimp-1 is relatively stable in 293T cells, a fusion with SUMO1 rendered it to rapid proteasomal degradation. Increase in SENP1 activity stabilized Blimp-1, while a decrease promoted its degradation. Our data indicate that SUMOylation of Blimp-1 regulates its …
Co-regulator recruitment and the mechanism of retinoic acid receptor synergy.
2002
Crystal structure and co-regulator interaction studies have led to a general mechanistic view of the initial steps of nuclear receptor (NR) action. Agonist-induced transconformation of the ligand-binding domain (holo-LBD) leads to the formation of co-activator complexes, and destabilizes the co-repressor complexes bound to the ligand-free (apo) LBD. However, the molecular basis of retinoid-X receptor (RXR) 'subordination' in heterodimers, an essential mechanism to avoid signalling pathway promiscuity, has remained elusive. RXR, in contrast to its heterodimer partner, cannot autonomously induce transcription on binding of cognate agonists. Here we show that RXR can bind ligand and recruit co…
Proteome-Wide Characterization of the RNA-Binding Protein RALY-Interactome Using the in Vivo-Biotinylation-Pulldown-Quant (iBioPQ) Approach
2013
RALY is a member of the heterogeneous nuclear ribonucleoproteins, a family of RNA-binding proteins generally involved in many processes of mRNA metabolism. No quantitative proteomic analysis of RALY-containing ribonucleoparticles (RNPs) has been performed so far, and the biological role of RALY remains elusive. Here, we present a workflow for the characterization of RALY's interaction partners, termed iBioPQ, that involves in vivo biotinylation of biotin acceptor peptide (BAP)-fused protein in the presence of the prokaryotic biotin holoenzyme synthetase of BirA so that it can be purified using streptavidin-coated magnetic beads, circumventing the need for specific antibodies and providing e…
Protein linear indices of the ‘macromolecular pseudograph α-carbon atom adjacency matrix’ in bioinformatics. Part 1: Prediction of protein stability …
2005
Abstract A novel approach to bio-macromolecular design from a linear algebra point of view is introduced. A protein’s total (whole protein) and local (one or more amino acid) linear indices are a new set of bio-macromolecular descriptors of relevance to protein QSAR/QSPR studies. These amino-acid level biochemical descriptors are based on the calculation of linear maps on R n [ f k ( x m i ) : R n → R n ] in canonical basis. These bio-macromolecular indices are calculated from the kth power of the macromolecular pseudograph α-carbon atom adjacency matrix. Total linear indices are linear functional on R n . That is, the kth total linear indices are linear maps from R n to the scalar R [ f k …