Cedric M Blouin

• PhD
• CRCN Inserm at Institut Curie

Maturation of conventional dendritic cells (cDCs) is crucial for maintaining tolerogenic safeguards against auto-immunity and for promoting immunogenic responses to pathogens and cancer. The subcellular mechanism for cDC maturation remains poorly defined. We show that cDCs mature by leveraging an internal reservoir of cholesterol (harnessed from ex...

Background Our prior research established that the uptake of tumor debris induces maturation in conventional dendritic cells (cDCs), transforming them into a molecular state termed ‘mregDC.’ This state entails a dampened ability to acquire new antigens, upregulated chemokine receptors for migration to lymphoid organs, and increased expression of MH...

Our prior research established that the uptake of tumor debris induces maturation in conventional dendritic cells (cDCs), transforming them into a molecular state termed mature DCs enriched in immunoregulatory molecules 'mregDC.' This state entails a dampened ability to acquire new antigens, upregulated chemokine receptors for migration to lymphoid...

Activation of JAK/STAT signaling by IFN-g requires partitioning of IFN-gR into specific lipid nanodomains at the plasma membrane. Using IFN-gR as a proxy, we investigated the role of actin dynamics in the formation and organization of lipid nanodomains, a process that remains poorly understood. We identified formin Dia2/DIAPH3 as a specific and Rho...

This symposium is the third PSL (Paris Sciences & Lettres) Chemical Biology meeting (2016, 2019, 2023) held at Institut Curie. This initiative originally started at Institut de Chimie des Substances Naturelles (ICSN) in Gif‐sur‐Yvette (2013, 2014), under the directorship of Professor Max Malacria, with a strong focus on chemistry. It was then conti...

Activation of the JAK–STAT pathway by type I interferons (IFNs) requires clathrin-dependent endocytosis of the IFN-α and -β receptor (IFNAR), indicating a role for endosomal sorting in this process. The molecular machinery that brings the selective activation of IFN-α/β-induced JAK–STAT signalling on endosomes remains unknown. Here we show that the...

A small‐molecule analogue of the formin FH2 domain inhibitor SMIFH2 was developed that selectively inhibits interferon‐induced JAK‐STAT signalling. Details of the study are reported by Cédric M. Blouin, Christophe Lamaze, Raphaël Rodriguez et al. in their Communication (DOI: 10.1002/anie.202205231).

Ein niedermolekulares Analogon des Formin‐FH2‐Domänen‐Inhibitors SMIFH2 wurde entwickelt, das selektiv die Interferon‐induzierte JAK‐STAT‐Signalgebung hemmt. Einzelheiten der Studie werden von Cédric M. Blouin, Christophe Lamaze, Raphaël Rodriguez et al. in ihrer Zuschrift vorgestellt (DOI: 10.1002/ange.202205231).

Interferons (IFN) are cytokines which, upon binding to cell surface receptors, trigger a series of downstream biochemical events including Janus Kinase (JAK) activation, phosphorylation of Signal Transducer and Activator of Transcription protein (STAT), translocation of pSTAT to the nucleus and transcriptional activation. Dysregulated IFN signallin...

Interferons (IFN) are cytokines which, upon binding to cell surface receptors, trigger a series of downstream biochemical events including Janus Kinase (JAK) activation, phosphorylation of Signal Transducer and Activator of Transcription protein (STAT), translocation of pSTAT to the nucleus and transcriptional activation. Dysregulated IFN signallin...

The cytokine interferon‐gamma (IFN‐γ) is a master regulator of innate and adaptive immunity involved in a broad array of human diseases that range from atherosclerosis to cancer. IFN‐γ exerts it signaling action by binding to a specific cell surface receptor, the IFN‐γ receptor (IFN‐γR), whose activation critically depends on its partition into lip...

Like most plasma membrane proteins, type I interferon (IFN) receptor (IFNAR) traffics from the outer surface to the inner compartments of the cell. Long considered as a passive means to simply control subunits availability at the plasma membrane, an array of new evidence establishes IFNAR endocytosis as an active contributor to the regulation of si...

Caveolins, major components of small plasma membrane invaginations called caveolae, play a role in signaling, particularly in mechanosignaling. These proteins are known to interact with a variety of effector molecules, including G-protein-coupled receptors, Src family kinases, ion channels, endothelial nitric oxide synthase (eNOS), adenylyl cyclase...

Caveolae are plasma membrane organelles that are, among many other features, involved in mechanosensing and mechanoprotection. Different tools have been developed to study caveolae-dependent mechanoprotection and had to be adapted to the tissue or cells studied, as these structures are found in almost every type of cells. This chapter focuses on a...

Tissue homeostasis requires regulation of cell-cell communication, which relies on signaling molecules and cell contacts. In skin epidermis, keratinocytes secrete factors transduced by melanocytes into signaling cues promoting their pigmentation and dendrite outgrowth, while melanocytes transfer melanin pigments to keratinocytes to convey skin phot...

This volume explores techniques used to study either the structure or the functions of caveolae and their components in several normal and pathophysiological situations. The chapters in this book cover topics such as selective visualization of caveolae by electron microscopy techniques; spatiotemporal analysis of caveolae dynamics and mechanics usi...

At the first EMBO conference dedicated to caveolae held in Le Pouliguen, France, May 12‐16 (http://meetings.embo.org/event/19-caveolae), round‐table discussions were used to address some of the long‐standing issues in the field and to decide upon a consensus view regarding key aspects of caveola biology. Here we summarise some of the frequently ask...

Tissue homeostasis requires regulation of cell-cell communication, which relies on signaling molecules and cell contacts. In skin epidermis, keratinocytes secrete specific factors transduced by melanocytes into signaling cues to promote their pigmentation and dendrite outgrowth, while melanocytes transfer melanin pigments to keratinocytes to convey...

Caveolin-3 is the major structural protein of caveolae in muscle. Mutations in the CAV3 gene cause different types of myopathies with altered membrane integrity and repair, expression of muscle proteins, and regulation of signaling pathways. We show here that myotubes from patients bearing the CAV3 P28L and R26Q mutations present a dramatic decreas...

Activation of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway by type I interferons (IFN) requires clathrin-dependent endocytosis of the IFN-α/β receptor (IFNAR). The molecular machinery that brings about the selective activation of IFN-α/β-induced JAK/STAT signaling on endosomes remains unknown. Here we show...

Caveolae are small invaginated pits that function as dynamic mechanosensors to buffer tension variations at the plasma membrane. Here we show that under mechanical stress, the EHD2 ATPase is rapidly released from caveolae, SUMOylated, and translocated to the nucleus, where it regulates the transcription of several genes including those coding for c...

Caveolin-3 is the major structural protein of caveolae in muscle cells. Mutations in the CAV3 gene cause different type of muscle disorders mostly characterized by defects in membrane integrity and repair, deregulation in the expression of various muscle proteins and deregulation of several muscle associated signaling pathways. We show here that my...

Membrane receptors control essential processes such as cell growth, adhesion, differentiation and metabolism through the activation of specific signaling pathways. Nowadays, these receptors are not only known to signal from the plasma membrane but also from intracellular compartments. Indeed, after being internalized with their ligands via differen...

Over the past decade, interest in caveolae biology has peaked. These small bulb-shaped plasma membrane invaginations of 50–80 nm diameter present in most cell types have been upgraded from simple membrane structures to a more complex bona fide organelle. However, although caveolae are involved in several essential cellular functions and pathologies...

L’interféron gamma (IFN-g) est une cytokine essentielle de l’immunité innée et adaptative pour lutter contre les infections virales, parasitaires ou même bactériennes et est impliqué dans les processus d’immuno-surveillance et d’échappement des tumeurs. Il est, entre autres, produit par les cellules natural killer (NK), les lymphocytes T CD4+ auxil...

The composition of the plasma membrane is highly complex and so are the cellular functions it conveys. Among those, the plasma membrane plays a key role in isolating the intracellular and extracellular environments. Nevertheless, communication between these 2 compartments has still to be maintained. If transmembrane receptors have long been known t...

Understanding how membrane nanoscale organization controls transmembrane receptors signaling activity remains a challenge. We studied interferon-γ receptor (IFN-γR) signaling in fibroblasts from homozygous patients with a T168N mutation in IFNGR2. By adding a neo-N-glycan on IFN-γR2 subunit, this mutation blocks IFN-γ activity by unknown mechanisms...

The molecular mechanisms and the biological functions of clathrin independent endocytosis (CIE) remain largely elusive. Alix (ALG-2 interacting protein X), has been assigned roles in membrane deformation and fission both in endosomes and at the plasma membrane. Using Alix ko cells, we show for the first time that Alix regulates fluid phase endocyto...

Fluorescence lifetime is usually defined as the average nanosecond-scale delay between excitation and emission of fluorescence. It has been established that lifetime measurements yield numerous indications on cellular processes such as interprotein and intraprotein mechanisms through fluorescent tagging and Förster resonance energy transfer. In thi...

Dysferlinopathies are a family of disabling muscular dystrophies with LGMD2B and Miyoshi myopathy as the main phenotypes. They are associated with molecular defects in DYSF, which encodes dysferlin, a key player in sarcolemmal homeostasis. Previous investigations have suggested that exon skipping may be a promising therapy for a subset of patients...

Fluorescence lifetime is usually defined as the average nanosecond-scale delay between excitation and emission of fluorescence. It has been established that lifetime measurement yields numerous indications on cellular processes such as inter-protein and intra-protein mechanisms through fluorescent tagging and Förster resonance energy transfer (FRET...

Along the years, the interest paid to the study of endocytosis has never wavered as this process plays such an essential role in many cellular functions. Cell growth, adhesion and differentiation, regulation of signaling induced by membrane receptors or infection by viral particles are all dependent on the entry of molecules into the cell. Once the...

Our view of endocytosis and membrane trafficking of transmembrane receptors has dramatically changed over the last 20 years. Several new endocytic routes have been discovered and mechanistically characterized in mammalian cells. Long considered as a passive means to terminate signaling through down-regulation of the number of activated receptors at...

Recent findings on clathrin-dependent and non clathrin-dependent endocytic routes are currently changing our classical view of endocytosis. Originally seen as a way for the cell to internalize membrane, receptors or various soluble molecules, this process is in fact directly linked to complex signaling pathways. Here, we review new insights in endo...

Adipose tissue lipoatrophy caused by caveolin gene deletion in mice is not linked to defective adipocyte differentiation. We show that adipose tissue development cannot be rescued by endothelial specific caveolin-1 re-expression, indicating primordial role of caveolin in mature adipocytes. Partial or total caveolin deficiency in adipocytes induced...

Introduction Les céramides sont reconnues comme des régulateurs négatifs de la voie de signalisation de l’insuline en inhibant la protéine kinase B (PKB/Akt) par deux mécanismes distincts : le premier impliquant la protéine kinase C ζɛτα (PKCζ), et l’autre la protéine phosphatase 2A (PP2A). Nous avons émis l’hypothèse que l’action des céramides, vi...

Ceramide is now recognized as a negative regulator of insulin signaling by impairing protein kinase B (PKB)/Akt activation. In different cells, two distinct mechanisms have been proposed to mediate ceramide inhibition of PKB/Akt: one involving atypical protein kinase C zeta (PKCzeta) and the other the protein phosphatase-2 (PP2A). We hypothesized t...

Caveolins form plasmalemnal invaginated caveolae. They also locate around intracellular lipid droplets but their role in this location remains unclear. By studying primary adipocytes that highly express caveolin-1, we characterized the impact of caveolin-1 deficiency on lipid droplet proteome and lipidome. We identified several missing proteins on...

Caveolins are primarily known as the main constituents of the protein coat of caveolae invaginations at the plasma membrane. They have also been found at the surface of intracellular lipid droplets but their function in this lipid storage organelle remains poorly understood. This paper reviews recent studies in adipocytes, the specialized cell type...

Caveolins, structural protein coats of caveolae primarily involved in membrane-related functions, have also been found associated to lipid droplets (LD), specialized organelles for fat storage. In the present study, we wanted to delineate the main features that govern the presence of caveolin-1 on adipocyte lipid droplets. Using either morphologica...

Lipid droplets have been considered for a long time as inert intracytoplasmic deposits formed within cells under various conditions. Recently, new tools and new approaches have been used to visualize and study these intracellular structures. This revealed new aspects of lipid droplets biology and pointed out their organized structure and dynamic co...

Lipid droplets have been considered for a long time as inert intracytoplasmic deposits formed within cells under various conditions. Recently, new tools and new approaches have been used to visualize and study these intracellular structures. This revealed new aspects of lipid droplets biology and pointed out their organized structure and dynamic co...