Influenza A virus induces PI4P production at the endoplasmic reticulum in an ATG16L1-dependent manner to promote the egress of viral ribonucleoproteins.

The genomic RNAs of influenza A viruses (IAVs) are replicated in the nucleus of infected cells in the form of viral ribonucleoproteins (vRNPs) before being exported to the cytoplasm. The small GTPase RAB11A is involved in the transport of vRNPs to the sites of viral assembly at the plasma membrane, but the molecular mechanisms involved remain largely unknown. Here we show that IAV infection remodels the architecture of the endoplasmic reticulum (ER) sheets, where vRNPs tend to accumulate in the absence of RAB11A.

Mass Spectrometry Reveals Novel Features of Tubulin Polyglutamylation in the Flagellum of .

Tubulin polyglutamylation is a key feature of eukaryotic cilia and flagella that is essential for their function. The diversity of enzymes catalyzing polyglutamylation with different specificities inspired the hypothesis of the tubulin code. In the protist parasite , nine different glutamylase enzymes are potentially involved in tubulin glutamylation.

Pathogenic mucorales: Deciphering their cell wall polysaccharidome and immunostimulatory potential.

Mucormycosis is an emerging infection caused by pathogenic filamentous fungal species belonging to the Order Mucorales. Mortality associated with mucormycosis is significantly high in patients with compromised immunity. As cell wall is the first fungal component to interact with the host immune system, we characterized cell wall organization and composition of the three most prevalent pathogenic species of Mucorales, , and studied their immunomodulatory potential.

In-host evolution of Yersinia enterocolitica during a chronic human infection.

Bacteria exhibit remarkable adaptability in response to selective pressures encountered during infection and antibiotic treatment. We characterize four Yersinia enterocolitica clonal isolates from successive bacteremia episodes that evolved within an elderly patient over 14 years. Their common evolution is characterized by a genome size reduction resulting in the loss of about a hundred genes and a so far undescribed deletion in the DNA gyrase gene gyrA conferring quinolone resistance.

Biogenesis of DNA-carrying extracellular vesicles by the dominant human gut methanogenic archaeon.

Extracellular vesicles (EVs) play many important roles in cells from all domains of life. Here, we characterize EVs produced by Methanobrevibacter smithii, the dominant methanogenic archaeon in the human gut, which contains a peptidoglycan cell wall. We show that M.

A novel approach to tagging tubulin reveals microtubule assembly dynamics of the axoneme in Trypanosoma brucei.

The protozoan parasite Trypanosoma brucei assembles a new flagellum while maintaining the existing one in the same cell. Our group has previously proposed a model where the mature flagellum is locked after construction to full length. To test this hypothesis directly, we monitored flagellum assembly dynamics through inducible expression of tubulin marked with an intragenic tag.

Retroviral adapters hijack the RNA helicase UPF1 in a CRM1/XPO1-dependent manner and reveal proviral roles of UPF1.

The hijacking of CRM1 export is an important step of the retroviral replication cycle. Here, we investigated the consequences of this hijacking for the host. During HTLV-1 infection, we identified that this hijacking by the viral protein Rex favours the association between CRM1 and the RNA helicase UPF1, leading to a decreased affinity of UPF1 for cellular RNA and its nuclear retention.

A Multiyear Longitudinal Harmonization Study of Quality Controls in Mass Spectrometry Proteomics Core Facilities.

Quality control procedures play a pivotal role in ensuring the reliability and consistency of data generated in mass spectrometry-based proteomics laboratories. However, the lack of standardized quality control practices across laboratories poses challenges for data comparability and reproducibility. In response, we conducted a harmonization study within proteomics laboratories of the Core for Life alliance with the aim of establishing a common quality control framework, which facilitates comprehensive quality assessment and identification of potential sources of performance drift.

Proteomic landscape of tunneling nanotubes reveals CD9 and CD81 tetraspanins as key regulators.

Tunneling nanotubes (TNTs) are open actin- and membrane-based channels, connecting remote cells and allowing direct transfer of cellular material (e.g. vesicles, mRNAs, protein aggregates) from the cytoplasm to the cytoplasm.

Phosphoproteomic analysis of the response to DNA damage in Trypanosoma brucei.

Damage to the genetic material of the cell poses a universal threat to all forms of life. The DNA damage response is a coordinated cellular response to a DNA break, key to which is the phosphorylation signaling cascade. Identifying which proteins are phosphorylated is therefore crucial to understanding the mechanisms that underlie it.

The extent of postpartum cardiac reverse remodeling is reflected in urine proteome.

The association of postpartum cardiac reverse remodeling (RR) with urinary proteome, particularly in pregnant women with cardiovascular (CV) risk factors who show long-term increased risk of cardiovascular disease and mortality is unknown. We aim to profile the urinary proteome in pregnant women with/without CV risk factors to identify proteins associated with postpartum RR. Our study included a prospective cohort of 32 healthy and 27 obese and/or hypertensive and/or diabetic pregnant women who underwent transthoracic echocardiography, pulse-wave-velocity, and urine collection at the 3rd trimester and 6 months postpartum.

Applying Reverse Genetics to Study Measles Virus Interactions with the Host.

The study of virus-host interactions is essential to achieve a comprehensive understanding of the viral replication process. The commonly used methods are yeast two-hybrid approach and transient expression of a single tagged viral protein in host cells followed by affinity purification of interacting cellular proteins and mass spectrometry analysis (AP-MS). However, by these approaches, virus-host protein-protein interactions are detected in the absence of a real infection, not always correctly compartmentalized, and for the yeast two-hybrid approach performed in a heterologous system.

The RBPome of influenza A virus NP-mRNA reveals a role for TDP-43 in viral replication.

Genome-wide approaches have significantly advanced our knowledge of the repertoire of RNA-binding proteins (RBPs) that associate with cellular polyadenylated mRNAs within eukaryotic cells. Recent studies focusing on the RBP interactomes of viral mRNAs, notably SARS-Cov-2, have revealed both similarities and differences between the RBP profiles of viral and cellular mRNAs. However, the RBPome of influenza virus mRNAs remains unexplored.

Mtfp1 ablation enhances mitochondrial respiration and protects against hepatic steatosis.

Hepatic steatosis is the result of imbalanced nutrient delivery and metabolism in the liver and is the first hallmark of Metabolic dysfunction-associated steatotic liver disease (MASLD). MASLD is the most common chronic liver disease and involves the accumulation of excess lipids in hepatocytes, inflammation, and cancer. Mitochondria play central roles in liver metabolism yet the specific mitochondrial functions causally linked to MASLD remain unclear.

Acetylation regulates the oligomerization state and activity of RNase J, the Helicobacter pylori major ribonuclease.

In the gastric pathogen Helicobacter pylori, post-transcriptional regulation relies strongly on the activity of the essential ribonuclease RNase J. Here, we elucidated the crystal and cryo-EM structures of RNase J and determined that it assembles into dimers and tetramers in vitro. We found that RNase J extracted from H.

Tunnelling nanotube formation is driven by Eps8/IRSp53-dependent linear actin polymerization.

Tunnelling nanotubes (TNTs) connect distant cells and mediate cargo transfer for intercellular communication in physiological and pathological contexts. How cells generate these actin-mediated protrusions to span lengths beyond those attainable by canonical filopodia remains unknown. Through a combination of micropatterning, microscopy, and optical tweezer-based approaches, we demonstrate that TNTs formed through the outward extension of actin achieve distances greater than the mean length of filopodia and that branched Arp2/3-dependent pathways attenuate the extent to which actin polymerizes in nanotubes, thus limiting their occurrence.

Encystation and Stress Responses under the Control of Ubiquitin-like Proteins in Pathogenic Amoebae.

Amoebae found in aquatic and terrestrial environments encompass various pathogenic species, including the parasite and the free-living . Both microorganisms pose significant threats to public health, capable of inducing life-threatening effects on humans. These amoebae exist in two cellular forms: trophozoites and cysts.

The cell wall lipoprotein CD1687 acts as a DNA binding protein during deoxycholate-induced biofilm formation in Clostridioides difficile.

The ability of bacterial pathogens to establish recurrent and persistent infections is frequently associated with their ability to form biofilms. Clostridioides difficile infections have a high rate of recurrence and relapses and it is hypothesized that biofilms are involved in its pathogenicity and persistence. Biofilm formation by C.

Yersiniomics, a Multi-Omics Interactive Database for Species.

The genus includes a large variety of nonpathogenic and life-threatening pathogenic bacteria, which cause a broad spectrum of diseases in humans and animals, such as plague, enteritis, Far East scarlet-like fever (FESLF), and enteric redmouth disease. Like most clinically relevant microorganisms, spp. are currently subjected to intense multi-omics investigations whose numbers have increased extensively in recent years, generating massive amounts of data useful for diagnostic and therapeutic developments.

Hemisynthetic alkaloids derived from trilobine are antimalarials with sustained activity in multidrug-resistant .

Malaria eradication requires the development of new drugs to combat drug-resistant parasites. We identified bisbenzylisoquinoline alkaloids isolated from that are active against blood stages. Synthesis of a library of 94 hemi-synthetic derivatives allowed to identify compound that kills multi-drug resistant clinical isolates in the nanomolar range (median IC ranging from 35 to 88 nM).