Publications by authors named "Nicolas Landrein"

Since the beginning of the COVID-19 pandemic, different viral vector-based and mRNA vaccines directed against the SARS-CoV-2 "S" spike glycoprotein have been developed and have shown a good profile in terms of safety and efficacy. Nevertheless, an unbiased comparison of vaccination efficiency, including post-vaccination neutralizing activity, between the different vaccines remains largely unavailable. This study aimed to compare the efficacy of one mRNA (BNT162b2) and two non-replicating adenoviral vector vaccines (ChAdOx1 nCoV-19 and Sputnik V) in a cohort of 1120 vaccinated Palestinian individuals who received vaccines on an availability basis and which displayed a unique diversity of genetic characteristics.

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In Trypanosoma brucei, transition fibres (TFs) form a nine-bladed pattern-like structure connecting the base of the flagellum to the flagellar pocket membrane. Despite the characterization of two TF proteins, CEP164C and T. brucei (Tb)RP2, little is known about the organization of these fibres.

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The flagellar pocket (FP) of the pathogen Trypanosoma brucei is an important single copy structure that is formed by the invagination of the pellicular membrane. It is the unique site of endo- and exocytosis and is required for parasite pathogenicity. The FP consists of distinct structural sub-domains with the least explored being the flagellar pocket collar (FPC).

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Background: In most trypanosomes, endo and exocytosis only occur at a unique organelle called the flagellar pocket (FP) and the flagellum exits the cell via the FP. Investigations of essential cytoskeleton-associated structures located at this site have revealed a number of essential proteins. The protein BILBO1 is located at the neck of the FP in a structure called the flagellar pocket collar (FPC) and is essential for biogenesis of the FPC and parasite survival.

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The flagellar pocket (FP) is the only endo- and exocytic organelle in most trypanosomes and, as such, is essential throughout the life cycle of the parasite. The neck of the FP is maintained enclosed around the flagellum via the flagellar pocket collar (FPC). The FPC is a macromolecular cytoskeletal structure and is essential for the formation of the FP and cytokinesis.

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Article Synopsis
  • Extended synaptotagmins (E-Syts) help with lipid transfer and maintaining lipid balance between the endoplasmic reticulum and plasma membrane.
  • TbE-Syt is a newly identified, unique E-Syt in a protist parasite that only has two C2 domains, making it the shortest known E-Syt.
  • The crystal structure analysis of TbE-Syt-C2B shows it can bind to lipids with calcium and PI(4,5)P, while C2A, lacking a calcium-binding site, may still interact with lipids differently, suggesting a method for lipid transfer between the ER and plasma membrane.
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is a protist parasite causing sleeping sickness and nagana in sub-Saharan Africa. has a single flagellum whose base contains a bulblike invagination of the plasma membrane called the flagellar pocket (FP). Around the neck of the FP on its cytoplasmic face is a structure called the flagellar pocket collar (FPC), which is essential for FP biogenesis.

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Trypanosoma brucei gambiense, an extracellular eukaryotic flagellate parasite, is the main etiological agent of human African trypanosomiasis (HAT) or sleeping sickness. Dendritic cells (DCs) play a pivotal role at the interface between innate and adaptive immune response and are implicated during HAT. In this study, we investigated the effects of T gambiense and its excreted/secreted factors (ESF) on the phenotype of human monocyte-derived DCs (Mo-DCs).

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  • Multiple morphological abnormalities of the sperm flagellum (MMAF) is a serious male infertility issue characterized by various sperm flagella defects, linked to genetic mutations affecting axonemal proteins.
  • Researchers analyzed whole-exome sequencing data from 78 affected individuals and discovered a homozygous deletion in the WDR66 gene in 7 cases, indicating a new genetic contributor to MMAF.
  • Further experiments, including studies on a related protein in Trypanosoma, demonstrated that this gene deletion impairs flagellar movement, thus confirming WDR66's role in male infertility related to MMAF.
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  • Spermatogenesis issues affect millions of men globally, but many remain undiagnosed.
  • The research identified 22 men with primary infertility linked to mutations in genes DNAH1, CFAP43, and CFAP44, confirmed through genetic sequencing.
  • CRISPR/Cas9 experiments on mice demonstrated that CFAP43 and CFAP44 are crucial for producing functional sperm flagella, underscoring their importance across different species.
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Trypanosoma brucei belongs to a group of unicellular, flagellated parasites that are responsible for human African trypanosomiasis. An essential aspect of parasite pathogenicity is cytoskeleton remodelling, which occurs during the life cycle of the parasite and is accompanied by major changes in morphology and organelle positioning. The flagellum originates from the basal bodies and exits the cell body through the flagellar pocket (FP) but remains attached to the cell body via the flagellum attachment zone (FAZ).

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Trypanosoma brucei gambiense is the main causative agent of Human African Trypanosomiasis (HAT), also known as sleeping sickness. Because of limited alternatives and treatment toxicities, new therapeutic options are urgently needed for patients with HAT. Sterol 14alpha-demethylase (CYP51) is a potential drug target but its essentiality has not been determined in T.

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The flagellar pocket (FP) of the pathogen Trypanosoma brucei is an important single copy structure that is formed by the invagination of the pellicular membrane. It is the unique site of endo- and exocytosis and is required for parasite pathogenicity. The FP consists of distinct structural sub-domains with the least explored being the annulus/horseshoe shaped flagellar pocket collar (FPC).

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Article Synopsis
  • Cilia and flagella are critical structures made of microtubules found in many cells, affecting processes like movement and cell shape, especially in vertebrate neurons where they impact synaptic function.
  • Researchers identified a new protein called hSAXO1, which is a human version of a MAP6-related protein that specifically associates with microtubules in centrioles and cilia.
  • The study reveals that hSAXO1 is essential for stabilizing these microtubules, affecting their length, and playing a significant role in the formation and function of cilia.
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In vertebrates the microtubule-associated proteins MAP6 and MAP6d1 stabilize cold-resistant microtubules. Cilia and flagella have cold-stable microtubules but MAP6 proteins have not been identified in these organelles. Here, we describe TbSAXO as the first MAP6-related protein to be identified in a protozoan, Trypanosoma brucei.

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Background: Trypanosoma brucei is a haemoflagellate pathogen of man, wild animals and domesticated livestock in central and southern Africa. In all life cycle stages this parasite has a single mitochondrion that contains a uniquely organised genome that is condensed into a flat disk-like structure called the kinetoplast. The kinetoplast is essential for insect form procyclic cells and therefore is a potential drug target.

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Trypanosoma brucei is a protozoan parasite that is used as a model organism to study such biological phenomena as gene expression, protein trafficking, and cytoskeletal biogenesis. In T. brucei, endocytosis and exocytosis occur exclusively through a sequestered organelle called the flagellar pocket (FP), an invagination of the pellicular membrane.

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The NIMA-related kinase 2 (NEK 2) has important cell cycle functions related to centriole integrity and splitting. Trypanosoma brucei does not possess centrioles, however, cytokinesis is coupled to basal body separation events. Here we report the first functional characterisation of a T.

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