Structural and functional characterization of CREB-binding protein (CREBBP) as a histone propionyltransferase.

In addition to histone acetylation, histone lysine propionylation (such as the H3K18Pr mark) has recently attracted significant attention as a common and abundant modification linking the cellular metabolic state and gene expression. CREB-binding protein (CREBBP) and EP300 are key histone acetyltransferases that play a critical role in gene expression through their catalytic activity. Although CREBBP and EP300 are homologous enzymes with high structural similarities, they exhibit both redundant and specific functions.

Cellular imbalance of specific RNA-binding proteins associates with harmful R-loops.

Understanding how the assembly of nascent mRNA into a ribonucleoprotein (mRNP) influences R-loop homeostasis is crucial for gaining insight into the cellular mechanisms that prevent genome instability. Here, we identify three RNA-binding proteins, Rie1, Rim4 and She2, whose expression levels are important to limit R-loop accumulation and, thus, to prevent DNA damage. Interestingly, Rim4 and She2 are overrepresented in CBP80-containing mRNPs formed in the absence of THO.

The MAST kinase KIN-4 carries out mitotic entry functions of Greatwall in C. elegans.

MAST-like, or Greatwall (Gwl), an atypical protein kinase related to the evolutionarily conserved MAST kinase family, is crucial for cell cycle control during mitotic entry. Mechanistically, Greatwall is activated by Cyclin B-Cdk1 phosphorylation of a 550 amino acids-long insertion in its atypical activation segment. Subsequently, Gwl phosphorylates Endosulfine and Arpp19 to convert them into inhibitors of PP2A-B55 phosphatase, thereby preventing early dephosphorylation of M-phase targets of Cyclin B-Cdk1.

Molecular Mechanisms of Response to Different Sources of Oxidative Stress.

Oxidative stress is a biological principle affecting all life on Earth and is also an important factor in the pathogen-host relationship. The pathogenic free-living amoeba has several pathways to cope with reactive oxygen species and the damage that they cause. In this study, we aimed to provide a comprehensive analysis of the amoeba's response to different sources of oxidative stress.

Candida albicans cells exhibit media specific proteomic profiles during induction of filamentation.

Candida albicans is an opportunist pathogen responsible for a broad spectrum of infections, from superficial mycosis to the systemic disease candidiasis. C. albicans has various morphological forms, including unicellular budding yeasts, filamentous pseudohyphae and true hyphae, and the ability to switch from yeast to hyphal forms is a key survival mechanism underlying the adaptation of the pathogen to the microenvironments encountered within the host.

CD40 Agonist on Patient-Derived Xenograft Mice for the Treatment of B-Cell Acute Lymphoblastic Leukemia.

Purpose: Cluster of differentiation 40 (CD40) is expressed on B-cell acute lymphoblastic leukemia (B-ALL) cases. However, the effect of CD40 activation on B-ALL cells has never been tested in vivo.

Experimental Design: The aim of our preclinical study was to investigate the therapeutic potential of a CD40 agonist in the treatment of B-ALL using patient-derived xenograft mouse models.

Bioorthogonal Monomycolate of Trehalose Disclosed the -Mycoloylation of Mycoloyltransferases and Other Cell Envelope Proteins in .

Protein mycoloylation is a recently identified unusual post-translational modification (PTM) exclusively observed in Mycobacteriales, an order of bacteria that includes several human pathogens. These bacteria possess a distinctive outer membrane, known as the mycomembrane, composed of very long-chain fatty acids called mycolic acids. It has been demonstrated that a few mycomembrane proteins undergo covalent modification with mycolic acids in the model organism through the action of mycoloyltransferase MytC.

Missense mutation in the activation segment of the kinase CK2 models Okur-Chung neurodevelopmental disorder and alters the hippocampal glutamatergic synapse.

Exome sequencing has enabled the identification of causative genes of monogenic forms of autism, amongst them, in 2016, CSNK2A1, the gene encoding the catalytic subunit of the kinase CK2, linking this kinase to Okur-Chung Neurodevelopmental Syndrome (OCNDS), a newly described neurodevelopmental condition with many symptoms resembling those of autism spectrum disorder. Thus far, no preclinical model of this condition exists. Here we describe a knock-in mouse model that harbors the K198R mutation in the activation segment of the α subunit of CK2.

Proteomic and secretomic comparison of young and aged dermal fibroblasts highlights cytoskeleton as a key component during aging.

Crucial for skin homeostasis, synthesis and degradation of extracellular matrix components are orchestrated by dermal fibroblasts. During aging, alterations of component expression, such as collagens and enzymes, lead to reduction of the mechanical cutaneous tension and defects of skin wound healing. The aim of this study was to better understand the molecular alterations underwent by fibroblasts during aging by comparing secretomic and proteomic signatures of fibroblasts from young (<35years) and aged (>55years) skin donors, in quiescence or TGF-stimulated conditions, using HLPC/MS.

Qualitative rather than quantitative phosphoregulation shapes the end of meiosis I in budding yeast.

Exit from mitosis is brought about by dramatic changes in the phosphoproteome landscape. A drop in Cyclin-dependent kinase (Cdk) activity, the master regulatory kinase, and activation of counteracting phosphatases such as Cdc14 in budding yeast, results in ordered substrate dephosphorylation, allowing entry into a new cell cycle and replication licensing. In meiosis however, two cell divisions have to be executed without intermediate DNA replication, implying that global phosphorylation and dephosphorylation have to be adapted to the challenges of meiosis.

Pyrroline-5-carboxylate metabolism protein complex detected in Arabidopsis thaliana leaf mitochondria.

Proline dehydrogenase (ProDH) and pyrroline-5-carboxylate (P5C) dehydrogenase (P5CDH) catalyse the oxidation of proline into glutamate via the intermediates P5C and glutamate-semialdehyde (GSA), which spontaneously interconvert. P5C and GSA are also intermediates in the production of glutamate from ornithine and α-ketoglutarate catalysed by ornithine δ-aminotransferase (OAT). ProDH and P5CDH form a fused bifunctional PutA enzyme in Gram-negative bacteria and are associated in a bifunctional substrate-channelling complex in Thermus thermophilus; however, the physical proximity of ProDH and P5CDH in eukaryotes has not been described.

Functional mapping of N-terminal residues in the yeast proteome uncovers novel determinants for mitochondrial protein import.

N-terminal ends of polypeptides are critical for the selective co-translational recruitment of N-terminal modification enzymes. However, it is unknown whether specific N-terminal signatures differentially regulate protein fate according to their cellular functions. In this work, we developed an in-silico approach to detect functional preferences in cellular N-terminomes, and identified in S.

An unconventional TOG domain is required for CLASP localization.

Cytoplasmic linker-associated proteins (CLASPs) form a conserved family of microtubule-associated proteins (MAPs) that maintain microtubules in a growing state by promoting rescue while suppressing catastrophe. CLASP function involves an ordered array of tumor overexpressed gene (TOG) domains and binding to multiple protein partners via a conserved C-terminal domain (CTD). In migrating cells, CLASPs concentrate at the cortex near focal adhesions as part of cortical microtubule stabilization complexes (CMSCs), via binding of their CTD to the focal adhesion protein PHLDB2/LL5β.

Mechanisms of nuclear pore complex disassembly by the mitotic Polo-like kinase 1 (PLK-1) in embryos.

The nuclear envelope, which protects and organizes the genome, is dismantled during mitosis. In the zygote, nuclear envelope breakdown (NEBD) of the parental pronuclei is spatially and temporally regulated during mitosis to promote the unification of the maternal and paternal genomes. Nuclear pore complex (NPC) disassembly is a decisive step of NEBD, essential for nuclear permeabilization.

Congenital mirror movements are associated with defective polymerisation of RAD51.

Background: Mirror movements are involuntary movements of one hand that mirror intentional movements of the other hand. Congenital mirror movements (CMM) is a rare genetic disorder with autosomal dominant inheritance, in which mirror movements are the main neurological manifestation. CMM is associated with an abnormal decussation of the corticospinal tract, a major motor tract for voluntary movements.

Mechanisms of Nuclear Pore Complex disassembly by the mitotic Polo-Like Kinase 1 (PLK-1) in embryos.

Unlabelled: The nuclear envelope, which protects and organizes the interphase genome, is dismantled during mitosis. In the zygote, nuclear envelope breakdown (NEBD) of the parental pronuclei is spatially and temporally regulated during mitosis to promote the unification of the parental genomes. During NEBD, Nuclear Pore Complex (NPC) disassembly is critical for rupturing the nuclear permeability barrier and removing the NPCs from the membranes near the centrosomes and between the juxtaposed pronuclei.

Extending the Range of SLIM-Labeling Applications: From Human Cell Lines in Culture to Whole-Organism Labeling.

The simple light isotope metabolic-labeling technique relies on the biosynthesis of amino acids from U-[C]-labeled molecules provided as the sole carbon source. The incorporation of the resulting U-[C]-amino acids into proteins presents several key advantages for mass-spectrometry-based proteomics analysis, as it results in more intense monoisotopic ions, with a better signal-to-noise ratio in bottom-up analysis. In our initial studies, we developed the simple light isotope metabolic (SLIM)-labeling strategy using prototrophic eukaryotic microorganisms, the yeasts and , as well as strains with genetic markers that lead to amino-acid auxotrophy.

Rabies virus P protein binds to TBK1 and interferes with the formation of innate immunity-related liquid condensates.

Viruses must overcome the interferon-mediated antiviral response to replicate and propagate into their host. Rabies virus (RABV) phosphoprotein P is known to inhibit interferon induction. Here, using a global mass spectrometry approach, we show that RABV P binds to TBK1, a kinase located at the crossroads of many interferon induction pathways, resulting in innate immunity inhibition.

The adaptive response to alternative carbon sources in the pathogen Candida albicans involves a remodeling of thiol- and glutathione-dependent redox status.

Candida albicans is an opportunist pathogen responsible for a large spectrum of infections, from superficial mycosis to systemic diseases known as candidiasis. During infection in vivo, Candida albicans must adapt to host microenvironments and this adaptive response is crucial for the survival of this organism, as it facilitates the effective assimilation of alternative carbon sources others than glucose. We performed a global proteomic analysis on the global changes in protein abundance in response to changes in micronutrient levels, and, in parallel, explored changes in the intracellular redox and metabolic status of the cells.