Search results for "RNA-binding protein"
showing 10 items of 194 documents
Heterogeneity and temporal dynamics of evolution of G1 human rotaviruses in a settled population.
2006
ABSTRACT A rotavirus sample collection from 19 consecutive years was used to investigate the heterogeneity and the dynamics of evolution of G1 rotavirus strains in a geographically defined population. Phylogenetic analysis of the VP7 gene sequences of G1P[8] human rotavirus strains showed the circulation of a heterogeneous population comprising three lineages and seven sublineages. Increases in the circulation of G1 rotaviruses were apparently associated with the introduction of novel G1 strains that exhibited multiple amino acid changes in antigenic regions involved in rotavirus neutralization compared to the strains circulating in the previous years. The emergence and/or introduction of G…
Cooperation of Two mRNA-Binding Proteins Drives Metabolic Adaptation to Iron Deficiency
2008
Summary Iron (Fe) is an essential cofactor for a wide range of cellular processes. We have previously demonstrated in yeast that Cth2 is expressed during Fe deficiency and promotes degradation of a battery of mRNAs leading to reprogramming of Fe-dependent metabolism and Fe storage. We report here that the Cth2-homologous protein Cth1 is transiently expressed during Fe deprivation and participates in the response to Fe deficiency through the degradation of mRNAs primarily involved in mitochondrially localized activities including respiration and amino acid biosynthesis. In parallel, wild-type cells, but not cth1 Δ cth2 Δ cells, accumulate mRNAs encoding proteins that function in glucose impo…
Unveiling novel interactions of histone chaperone Asf1 linked to TREX-2 factors Sus1 and Thp1
2014
13 páginas, 7 figuras, 2 yablas
Saccharomyces cerevisiae Glutaredoxin 5-deficient Cells Subjected to Continuous Oxidizing Conditions Are Affected in the Expression of Specific Sets …
2004
The Saccharomyces cerevisiae GRX5 gene codes for a mitochondrial glutaredoxin involved in the synthesis of iron/sulfur clusters. Its absence prevents respiratory growth and causes the accumulation of iron inside cells and constitutive oxidation of proteins. Null ⌬grx5 mu- tants were used as an example of continuously oxidized cells, as opposed to situations in which oxidative stress is instantaneously caused by addition of external oxi- dants. Whole transcriptome analysis was carried out in the mutant cells. The set of genes whose expression was affected by the absence of Grx5 does not significantly overlap with the set of genes affected in respiratory petite mutants. Many Aft1-dependent ge…
Rpb4 and Puf3 imprint and post-transcriptionally control the stability of a common set of mRNAs in yeast
2020
ABSTRACTGene expression involving RNA polymerase II is regulated by the concerted interplay between mRNA synthesis and degradation, crosstalk in which mRNA decay machinery and transcription machinery respectively impact transcription and mRNA stability. Rpb4, and likely dimer Rpb4/7, seem the central components of the RNA pol II governing these processes. In this work we unravel the molecular mechanisms participated by Rpb4 that mediate the posttranscriptional events regulating mRNA imprinting and stability. By RIP-Seq, we analyzed genome-wide the association of Rpb4 with mRNAs and demonstrated that it targeted a large population of more than 1400 transcripts. A group of these mRNAs was als…
The Lsm1-7/Pat1 complex binds to stress-activated mRNAs and modulates the response to hyperosmotic shock.
2018
RNA-binding proteins (RBPs) establish the cellular fate of a transcript, but an understanding of these processes has been limited by a lack of identified specific interactions between RNA and protein molecules. Using MS2 RNA tagging, we have purified proteins associated with individual mRNA species induced by osmotic stress, STL1 and GPD1. We found members of the Lsm1-7/Pat1 RBP complex to preferentially bind these mRNAs, relative to the non-stress induced mRNAs, HYP2 and ASH1. To assess the functional importance, we mutated components of the Lsm1-7/Pat1 RBP complex and analyzed the impact on expression of osmostress gene products. We observed a defect in global translation inhibition under…
H1° mRNA-containing complexes in rat brain cells. In: Proceedings of the Abstracts
2015
Post-transcriptional regulation of gene expression depends on RNA-binding proteins (RBPs), which are able to regulate translation, stability and subcellular localization of mRNAs [1]. RNA-protein complexes start to be built up since transcription; some proteins remain then bound to the transcript, while others behave as only transient components. In the developing nervous system of mammals, the postnatal production of the histone variants H1° and H3.3 is mainly regulated at the post-transcriptional level. Synthesis and incorporation into chromatin of the two histone proteins has been suggested to be involved in the epigenetic regulation of gene expression, both in normal brain development a…
Melanoma cells release extracellular vesicle which contain H1° linker histone as well as RNA-binding proteins which bind to the H1° mRNA
2015
We previously demonstrated that G26/24 oligodendroglioma cells release EVs that contain proteins, such as FasL and TRAIL, which induce apoptosis in rat cortical neurons [1] and astrocytes [2]. We also reported that cancer cells use EVs for transferring, into the environment [3], proteins such as extracellular matrix remodelling proteases [4], and H1°, a differentiation-specific histone [5]. In particular, by releasing H1°, cells could escape differentiation cues [5]. To verify the role of EVs in releasing specific proteins and mRNAs, in this study we used as a model A375 melanoma cells. METHODS EVs were purified from cell culture media as previously reported [1, 2]. T1 RNase-protection assa…
Expression and intracellular localization of H1° mRNA-containing complexes in developing rat brain and astrocytes
2015
INTRODUCTION: Post-transcriptional regulation of gene expression relies on RNA-binding proteins (RBPs), which regulate intracellular transport, stability, and translation of mRNAs [1]. We previously identified a set of proteins which interact with mRNAs encoding H1° and H3.3 histones [2-5]. All these proteins are probably part of a ribonucleoprotein particle [6]. Here we report more details on the expression and intracellular localization of some of these RBPs, during rat brain development and in isolated rat astrocytes. METHODS: Affinity chromatography was performed as already described [6]. Preparation of total lysates and cellular sub-fractions was done as reported in [3]. Possible co-lo…
The crystal structure of bacteriophage Qβ at 3.5 å resolution
1996
Abstract Background: The capsid protein subunits of small RNA bacteriophages form a T=3 particle upon assembly and RNA encapsidation. Dimers of the capsid protein repress translation of the replicase gene product by binding to the ribosome binding site and this interaction is believed to initiate RNA encapsidation. We have determined the crystal structure of phage Qβ with the aim of clarifying which factors are the most important for particle assembly and RNA interaction in the small phages. Results The crystal structure of bacteriophage Qβ determined at 3.5 a resolution shows that the capsid is stabilized by disulfide bonds on each side of the flexible loops that are situated around the fi…