72 research outputs found
Symptoms of Infarction in Women: Is There a Real Difference Compared to Men? A Systematic Review of the Literature with Meta-Analysis
(1) Context: The management of acute coronary syndrome (ACS) is based on a rapid diagnosis. The aim of this study was to focus on the ACS symptoms differences according to gender, in order to contribute to the improvement of knowledge regarding the clinical presentation in women. (2) Methods: We searched for relevant literature in two electronic databases, and analyzed the symptom presentation for patients with suspected ACS. Fifteen prospective studies were included, with a total sample size of 10,730. (3) Results: During a suspected ACS, women present more dyspnea, arm pain, nausea and vomiting, fatigue, palpitations and pain at the shoulder than men, with RR (95%CI) of 1.13 [1.10; 1.17], 1.30 [1.05; 1.59], 1,40 [1.26; 1.56], 1.08 [1.01; 1.16], 1.67 [1.49; 1.86], 1.78 [1.02; 3.13], respectively. They are older by (95%CI) 4.15 [2.28; 6.03] years compared to men. The results are consistent in the analysis of the ACS confirmed subgroup. (4) Conclusions: We have shown that there is a gender-based symptomatic difference and a female presentation for ACS. The "typical" or "atypical" semiology of ACS symptoms should no longer be used
TLRs1-10 Protein Expression in Circulating Human White Blood Cells during Bacterial and COVID-19 Infections
Introduction: Toll-like receptors play crucial roles in the sepsis-induced systemic inflammatory response. Septic shock mortality correlates with overexpression of neutrophilic TLR2 and TLR9, while the role of TLR4 overexpression remains a debate. In addition, TLRs are involved in the pathogenesis of viral infections such as COVID-19, where the single-stranded RNA of SARS-CoV-2 is recognized by TLR7 and TLR8, and the spike protein activates TLR4. Methods: In this study, we conducted a comprehensive analysis of TLRs 1â10 expressions in white blood cells from 71 patients with bacterial and viral infections. Patients were divided into 4 groups based on disease type and severity (sepsis, septic shock, moderate, and severe COVID-19) and compared to 7 healthy volunteers. Results: We observed a significant reduction in the expression of TLR4 and its co-receptor CD14 in septic shock neutrophils compared to the control group (p < 0.001). Severe COVID-19 patients exhibited a significant increase in TLR3 and TLR7 levels in neutrophils compared to controls (p < 0.05). Septic shock patients also showed a similar increase in TLR7 in neutrophils along with elevated intermediate monocytes (CD14+CD16+) compared to the control group (p < 0.005 and p < 0.001, respectively). However, TLR expression remained unchanged in lymphocytes. Conclusion: This study provides further insights into the mechanisms of TLR activation in various infectious conditions. Additional analysis is needed to assess their correlation with patient outcome and to evaluate the impact of TLR-pathway modulation during septic shock and severe COVID-19
C11orf70 Mutations Disrupting the Intraflagellar Transport-Dependent Assembly of Multiple Axonemal Dyneins Cause Primary Ciliary Dyskinesia
Primary ciliary dyskinesia (PCD) is a genetically and phenotypically heterogeneous disorder characterized by destructive respiratory disease and laterality abnormalities due to randomized left-right body asymmetry. PCD is mostly caused by mutations affecting the core axoneme structure of motile cilia that is essential for movement. Genes that cause PCD when mutated include a group that encode proteins essential for the assembly of the ciliary dynein motors and the active transport process that delivers them from their cytoplasmic assembly site into the axoneme. We screened a cohort of affected individuals for disease-causing mutations using a targeted next generation sequencing panel and identified two unrelated families (three affected children) with mutations in the uncharacterized C11orf70 gene (official gene name CFAP300). The affected children share a consistent PCD phenotype from early life with laterality defects and immotile respiratory cilia displaying combined loss of inner and outer dynein arms (IDA+ODA). Phylogenetic analysis shows C11orf70 is highly conserved, distributed across species similarly to proteins involved in the intraflagellar transport (IFT)-dependant assembly of axonemal dyneins. Paramecium C11orf70 RNAi knockdown led to combined loss of ciliary IDA+ODA with reduced cilia beating and swim velocity. Tagged C11orf70 in Paramecium and Chlamydomonas localizes mainly in the cytoplasm with a small amount in the ciliary component. IFT139/TTC21B (IFT-A protein) and FLA10 (IFT kinesin) depletion experiments show that its transport within cilia is IFT dependent. During ciliogenesis, C11orf70 accumulates at the ciliary tips in a similar distribution to the IFT-B protein IFT46. In summary, C11orf70 is essential for assembly of dynein arms and C11orf70 mutations cause defective cilia motility and PCD
Mutations in Outer Dynein Arm Heavy Chain DNAH9 Cause Motile Cilia Defects and Situs Inversus
International audienceMotile cilia move body fluids and gametes and the beating of cilia lining the airway epithelial surfaces ensures that they are kept clear and protected from inhaled pathogens and consequent respiratory infections. Dynein motor proteins provide mechanical force for cilia beating. Dynein mutations are a common cause of primary ciliary dyskinesia (PCD), an inherited condition characterized by deficient mucociliary clearance and chronic respiratory disease coupled with laterality disturbances and subfertility. Using next-generation sequencing, we detected mutations in the ciliary outer dynein arm (ODA) heavy chain gene DNAH9 in individuals from PCD clinics with situs inversus and in one case male infertility. DNAH9 and its partner heavy chain DNAH5 localize to type 2 ODAs of the distal cilium and in DNAH9-mutated nasal respiratory epithelial cilia we found a loss of DNAH9/DNAH5-containing type 2 ODAs that was restricted to the distal cilia region. This confers a reduced beating frequency with a subtle beating pattern defect affecting the motility of the distal cilia portion. 3D electron tomography ultrastructural studies confirmed regional loss of ODAs from the distal cilium, manifesting as either loss of whole ODA or partial loss of ODA volume. Paramecium DNAH9 knockdown confirms an evolutionarily conserved function for DNAH9 in cilia motility and ODA stability. We find that DNAH9 is widely expressed in the airways, despite DNAH9 mutations appearing to confer symptoms restricted to the upper respiratory tract. In summary, DNAH9 mutations reduce cilia function but some respiratory mucociliary clearance potential may be retained, widening the PCD disease spectrum
Comparison of Short- and Long-Term Mortality in Patients with or without Cancer Admitted to the ICU for Septic Shock: A Retrospective Observational Study
Introduction: Cancer patients are at high risk of developing septic shock (SSh) and are increasingly admitted to ICU given their improved long-term prognosis. We, therefore, compared the prognosis of cancer and non-cancer patients with SSh. Methods: We conducted a monocentric, retrospective cohort study (2013–2019) on patients admitted to ICU for SSh. We compared the clinical characteristics and management and studied short- and long-term mortality with ICU and in-hospital mortality and 1-year survival according to cancer status. Results: We analyzed 239 ICU stays in 210 patients, 59.5% of whom were men (n = 125), with a median age of 66.5 (IQR 56.3–77.0). Of the 121 cancer patients (57.6% of all patients), 70 had solid tumors (33.3%), and 51 had hematological malignancies (24.3%). When comparing ICU stays of patients with versus without cancer (n = 148 vs. n = 91 stays, respectively), mortality reached 30.4% (n = 45) vs. 30.0% (n = 27) in the ICU (p = 0.95), and 41.6% (n = 59) vs. 35.6% (n = 32) in hospital (p = 0.36), respectively. ICU length of stay (LOS) was 5.0 (2.0–11.3) vs. 6.0 (3.0–15.0) days (p = 0.27), whereas in-hospital LOS was 25.5 (13.8–42.0) vs. 19.5 (10.8–41.0) days (p = 0.33). Upon multivariate analysis, renal replacement therapy (OR = 2.29, CI95%: 1.06–4.93, p = 0.03), disseminated intravascular coagulation (OR = 5.89, CI95%: 2.49–13.92, p < 0.01), and mechanical ventilation (OR = 7.85, CI95%: 2.90–21.20, p < 0.01) were associated with ICU mortality, whereas malignancy, hematological, or solid tumors were not (OR = 1.41, CI95%: 0.65–3.04; p = 0.38). Similarly, overall cancer status was not associated with in-hospital mortality (OR = 1.99, CI95%: 0.98–4.03, p = 0.06); however, solid cancers were associated with increased in-hospital mortality (OR = 2.52, CI95%: 1.12–5.67, p = 0.03). Lastly, mortality was not significantly different at 365-day follow-up between patients with and without cancer. Conclusions: In-hospital and ICU mortality, as well as LOS, were not different in SSh patients with and without cancer, suggesting that malignancies should no longer be considered a barrier to ICU admission
Study of the CEP90-FOPNL and OFD1 complex in the basal body anchoring process
Les centrioles sont des structures cellulaires trĂšs conservĂ©es au cours de lâĂ©volution. Ils sont organisĂ©s en symĂ©trie 9 de triplets de microtubules. Le centrosome est le principal centre organisateur des microtubules et est nĂ©cessaire pour assurer des processus fondamentaux tels que la division et la polaritĂ© cellulaire. Lorsque que les conditions le permettent, le centriole pĂšre est capable de migrer et de sâancrer Ă une membrane cellulaire pour former un cil. Le processus dâancrage fait intervenir la partie distale du centriole pĂšre et notamment les appendices distaux. Au cours de la ciliogenĂšse, le centriole pĂšre subit une maturation et est appelĂ© corps basal. Les appendices distaux forment les fibres de transition et dĂ©terminent la partie antĂ©rieure de la zone de transition qui joue un rĂŽle de filtre nĂ©cessaire pour assurer la spĂ©cificitĂ© de la composition protĂ©ique et lipidique du cil. Au cours de lâĂ©volution, la structure des cils est trĂšs conservĂ©e malgrĂ© lâobservation de variations structurales entre diffĂ©rents organismes. Les cils jouent un rĂŽle essentiel dans la signalisation et/ou de motilitĂ©. Par consĂ©quence, chez lâhomme, les dĂ©fauts ciliaires sont Ă lâorigine de maladies gĂ©nĂ©tiques rares causant des syndromes poly-malformatifs regroupĂ©s sous le nom de ciliopathies. Au cours de ma thĂšse je me suis intĂ©ressĂ© Ă identifier de nouveaux acteurs de lâancrage des corps basaux en utilisant deux modĂšles complĂ©mentaires : des cultures de cellules humaines et lâorganisme unicellulaire Paramecium Tetraurelia. Les corps basaux de la paramĂ©cie sont tous ancrĂ©s Ă la membrane plasmique sans passer par une Ă©tape centriolaire. Par consĂ©quence chez cet organisme des dĂ©fauts dâancrage se caractĂ©risent par la prĂ©sence de corps basaux non ancrĂ©s dans le cytoplasme et facilement observables. GrĂące Ă ce modĂšle les membres de lâĂ©quipe ont dĂ©jĂ caractĂ©risĂ©s lâimplication de 4 protĂ©ines dans lâancrage des corps basaux : Cen2, OFD1, FOPNL et Cen3. Chez lâhomme FOPNL, OFD1 et MNR forment un complexe nĂ©cessaire Ă la ciliogenĂšse, MNR et OFD1 Ă©tant toutes les deux impliquĂ©es dans des ciliopathies. Jâai recherchĂ© de nouveaux acteurs de lâancrage des corps basaux en rĂ©alisant une technique dâidentification par proximitĂ©, la BioID, en utilisant FOPNL comme appĂąt. Nous avons dĂ©terminĂ© que la protĂ©ine CEP90 est localisĂ©e dans lâenvironnement proche de FOPNL. Dans les cellules humaines, CEP90 partage la mĂȘme localisation que FOPNL et OFD1 aux centrioles et aux satellites centriolaires et est aussi impliquĂ©e dans des ciliopathies. En utilisant une technique dâimagerie super-rĂ©solutive appelĂ©e microscopie Ă expansion, nous montrons que CEP90, FOPNL et OFD1 sont organisĂ©es en symĂ©trie 9 en partie distale des centrioles et des corps basaux, proche de la protĂ©ine des appendices distaux CEP83. Le recrutement aux centrioles et corps basaux de CEP90, FOPNL et OFD1 est interdĂ©pendant et lâabsence dâune de ces protĂ©ines entraine des dĂ©fauts dâancrage des corps basaux chez la paramĂ©cie. Chez les mammifĂšre, la dĂ©plĂ©tion de FOPNL ou CEP90 affecte le recrutement de 3 protĂ©ines de appendices distaux (CEP83, CEP89 et CEP164) impliquĂ©es dans lâancrage des corps basaux. Dans les cellules de mammifĂšres, nous avons dĂ©montrĂ© que CEP90 et OFD1 sont recrutĂ©es trĂšs prĂ©cocement sur les procentrioles au cours de la duplication et que la co-surexpression de MNR et CEP90 est suffisante pour recruter OFD1 et CEP83 le long du rĂ©seau de microtubules. La surexpression de CEP90 seule forme des agrĂ©gats capables de recruter OFD1 et CEP83. Lâensemble de ces rĂ©sultats apporte un Ă©clairage nouveau sur le processus dâancrage des corps basaux. Le recrutement prĂ©coce du complexe CEP90, FOPNL et OFD1 nous a conduit Ă proposer que ce complexe permettait de spĂ©cifier la future localisation des appendices distaux. Enfin, dans cette thĂšse nous montrons que le complexe CEP90, FOPNL et OFD1 est fonctionnellement conservĂ© chez la paramĂ©cie et les cellules de mammifĂšres.Centrioles are highly conserved structures throughout evolution. They are organized in a 9-fold symmetry of microtubule triplets. In animals, centrioles are building blocks of the centrosome. The centrosome is the main organizing center of microtubules and is necessary for fundamental processes such as cell division and polarity. Under specific conditions, the mother centriole is able to migrate and anchor to a cell membrane to build a cilium. The anchoring process involves the distal extremity of the mother centriole and in particular the distal appendages. During ciliogenesis, the mother centriole matures and is called the basal body. The distal appendages mature in transition fibers and determine the proximal extremity of the transition zone, which acts as a filter to ensure the specificity of the protein and lipid composition of the cilium. During evolution, the structure of cilia is highly conserved, despite variations between organisms have been observed. Cilia play an essential role in signaling and / or motility. Consequently, in humans, rare genetic diseases originate from ciliary defects causing poly-malformation syndromes called ciliopathies. During my thesis, I was interested in identifying new actors of basal bodies anchoring using two complementary models: human cell cultures and Paramecium Tetraurelia. The basal bodies in Paramecium are all anchored to the plasma membrane and did not display any centriolar stages. Consequently, in this organism, anchoring defects are characterized by the presence of easily observable non-anchored basal bodies. Using this model, members of the team have already characterized the involvement of 4 proteins in the basal bodies anchoring: Cen2, OFD1, FOPNL and Cen3. In human, FOPNL, OFD1 and MNR form a complex involved in ciliogenesis, MNR and OFD1 both being involved in ciliopathies. To The search of novel actors involved in the basal body anchoring process has been achieved using BioID, a proximity identification technic, using FOPNL as a bait. We determined that the CEP90 protein is localized in the close environment of FOPNL. In human cells, CEP90 shares the same localization as FOPNL and OFD1 at centrioles and centriolar satellites and is also involved in ciliopathy. Using a super-resolution imaging technique called expansion microscopy, we show that CEP90, FOPNL, and OFD1 are organized in 9-fold symmetry at the distal part of the centrioles and basal bodies, close to the distal appendage protein CEP83. The recruitment of CEP90, FOPNL and OFD1 at basal bodies is interdependent and the absence of one of these proteins leads to basal body anchoring defects in Paramecium. In mammals, the depletion of FOPNL or CEP90 affects the recruitment of 3 distal appendage proteins (CEP83, CEP89 and CEP164). In mammalian cells, we demonstrated that CEP90 and OFD1 are recruited during duplication on early born procentrioles and that the co-overexpression of MNR and CEP90 is sufficient to recruit OFD1 and CEP83 along the microtubule network. Altogether these results shed new light on the basal body anchoring process. In addition, the early recruitment of CEP90, FOPNL and OFD1 complex on newly born procentrioles led us to propose that the localization of the complex specify the future location of the distal appendages. Finally, in this thesis, we show that CEP90, FOPNL and OFD1 is functionally conserved from Paramecium to mammalian cells despite it is absent in some phyla such as Drosophila and C.elegans
Etude du complexe CEP90-FOPNL et OFD1 dans le processus dâancrage des corps basaux
Centrioles are highly conserved structures throughout evolution. They are organized in a 9-fold symmetry of microtubule triplets. In animals, centrioles are building blocks of the centrosome. The centrosome is the main organizing center of microtubules and is necessary for fundamental processes such as cell division and polarity. Under specific conditions, the mother centriole is able to migrate and anchor to a cell membrane to build a cilium. The anchoring process involves the distal extremity of the mother centriole and in particular the distal appendages. During ciliogenesis, the mother centriole matures and is called the basal body. The distal appendages mature in transition fibers and determine the proximal extremity of the transition zone, which acts as a filter to ensure the specificity of the protein and lipid composition of the cilium. During evolution, the structure of cilia is highly conserved, despite variations between organisms have been observed. Cilia play an essential role in signaling and / or motility. Consequently, in humans, rare genetic diseases originate from ciliary defects causing poly-malformation syndromes called ciliopathies. During my thesis, I was interested in identifying new actors of basal bodies anchoring using two complementary models: human cell cultures and Paramecium Tetraurelia. The basal bodies in Paramecium are all anchored to the plasma membrane and did not display any centriolar stages. Consequently, in this organism, anchoring defects are characterized by the presence of easily observable non-anchored basal bodies. Using this model, members of the team have already characterized the involvement of 4 proteins in the basal bodies anchoring: Cen2, OFD1, FOPNL and Cen3. In human, FOPNL, OFD1 and MNR form a complex involved in ciliogenesis, MNR and OFD1 both being involved in ciliopathies. To The search of novel actors involved in the basal body anchoring process has been achieved using BioID, a proximity identification technic, using FOPNL as a bait. We determined that the CEP90 protein is localized in the close environment of FOPNL. In human cells, CEP90 shares the same localization as FOPNL and OFD1 at centrioles and centriolar satellites and is also involved in ciliopathy. Using a super-resolution imaging technique called expansion microscopy, we show that CEP90, FOPNL, and OFD1 are organized in 9-fold symmetry at the distal part of the centrioles and basal bodies, close to the distal appendage protein CEP83. The recruitment of CEP90, FOPNL and OFD1 at basal bodies is interdependent and the absence of one of these proteins leads to basal body anchoring defects in Paramecium. In mammals, the depletion of FOPNL or CEP90 affects the recruitment of 3 distal appendage proteins (CEP83, CEP89 and CEP164). In mammalian cells, we demonstrated that CEP90 and OFD1 are recruited during duplication on early born procentrioles and that the co-overexpression of MNR and CEP90 is sufficient to recruit OFD1 and CEP83 along the microtubule network. Altogether these results shed new light on the basal body anchoring process. In addition, the early recruitment of CEP90, FOPNL and OFD1 complex on newly born procentrioles led us to propose that the localization of the complex specify the future location of the distal appendages. Finally, in this thesis, we show that CEP90, FOPNL and OFD1 is functionally conserved from Paramecium to mammalian cells despite it is absent in some phyla such as Drosophila and C.elegans.Les centrioles sont des structures cellulaires trĂšs conservĂ©es au cours de lâĂ©volution. Ils sont organisĂ©s en symĂ©trie 9 de triplets de microtubules. Le centrosome est le principal centre organisateur des microtubules et est nĂ©cessaire pour assurer des processus fondamentaux tels que la division et la polaritĂ© cellulaire. Lorsque que les conditions le permettent, le centriole pĂšre est capable de migrer et de sâancrer Ă une membrane cellulaire pour former un cil. Le processus dâancrage fait intervenir la partie distale du centriole pĂšre et notamment les appendices distaux. Au cours de la ciliogenĂšse, le centriole pĂšre subit une maturation et est appelĂ© corps basal. Les appendices distaux forment les fibres de transition et dĂ©terminent la partie antĂ©rieure de la zone de transition qui joue un rĂŽle de filtre nĂ©cessaire pour assurer la spĂ©cificitĂ© de la composition protĂ©ique et lipidique du cil. Au cours de lâĂ©volution, la structure des cils est trĂšs conservĂ©e malgrĂ© lâobservation de variations structurales entre diffĂ©rents organismes. Les cils jouent un rĂŽle essentiel dans la signalisation et/ou de motilitĂ©. Par consĂ©quence, chez lâhomme, les dĂ©fauts ciliaires sont Ă lâorigine de maladies gĂ©nĂ©tiques rares causant des syndromes poly-malformatifs regroupĂ©s sous le nom de ciliopathies. Au cours de ma thĂšse je me suis intĂ©ressĂ© Ă identifier de nouveaux acteurs de lâancrage des corps basaux en utilisant deux modĂšles complĂ©mentaires : des cultures de cellules humaines et lâorganisme unicellulaire Paramecium Tetraurelia. Les corps basaux de la paramĂ©cie sont tous ancrĂ©s Ă la membrane plasmique sans passer par une Ă©tape centriolaire. Par consĂ©quence chez cet organisme des dĂ©fauts dâancrage se caractĂ©risent par la prĂ©sence de corps basaux non ancrĂ©s dans le cytoplasme et facilement observables. GrĂące Ă ce modĂšle les membres de lâĂ©quipe ont dĂ©jĂ caractĂ©risĂ©s lâimplication de 4 protĂ©ines dans lâancrage des corps basaux : Cen2, OFD1, FOPNL et Cen3. Chez lâhomme FOPNL, OFD1 et MNR forment un complexe nĂ©cessaire Ă la ciliogenĂšse, MNR et OFD1 Ă©tant toutes les deux impliquĂ©es dans des ciliopathies. Jâai recherchĂ© de nouveaux acteurs de lâancrage des corps basaux en rĂ©alisant une technique dâidentification par proximitĂ©, la BioID, en utilisant FOPNL comme appĂąt. Nous avons dĂ©terminĂ© que la protĂ©ine CEP90 est localisĂ©e dans lâenvironnement proche de FOPNL. Dans les cellules humaines, CEP90 partage la mĂȘme localisation que FOPNL et OFD1 aux centrioles et aux satellites centriolaires et est aussi impliquĂ©e dans des ciliopathies. En utilisant une technique dâimagerie super-rĂ©solutive appelĂ©e microscopie Ă expansion, nous montrons que CEP90, FOPNL et OFD1 sont organisĂ©es en symĂ©trie 9 en partie distale des centrioles et des corps basaux, proche de la protĂ©ine des appendices distaux CEP83. Le recrutement aux centrioles et corps basaux de CEP90, FOPNL et OFD1 est interdĂ©pendant et lâabsence dâune de ces protĂ©ines entraine des dĂ©fauts dâancrage des corps basaux chez la paramĂ©cie. Chez les mammifĂšre, la dĂ©plĂ©tion de FOPNL ou CEP90 affecte le recrutement de 3 protĂ©ines de appendices distaux (CEP83, CEP89 et CEP164) impliquĂ©es dans lâancrage des corps basaux. Dans les cellules de mammifĂšres, nous avons dĂ©montrĂ© que CEP90 et OFD1 sont recrutĂ©es trĂšs prĂ©cocement sur les procentrioles au cours de la duplication et que la co-surexpression de MNR et CEP90 est suffisante pour recruter OFD1 et CEP83 le long du rĂ©seau de microtubules. La surexpression de CEP90 seule forme des agrĂ©gats capables de recruter OFD1 et CEP83. Lâensemble de ces rĂ©sultats apporte un Ă©clairage nouveau sur le processus dâancrage des corps basaux. Le recrutement prĂ©coce du complexe CEP90, FOPNL et OFD1 nous a conduit Ă proposer que ce complexe permettait de spĂ©cifier la future localisation des appendices distaux. Enfin, dans cette thĂšse nous montrons que le complexe CEP90, FOPNL et OFD1 est fonctionnellement conservĂ© chez la paramĂ©cie et les cellules de mammifĂšres
Etude du complexe CEP90-FOPNL et OFD1 dans le processus dâancrage des corps basaux
Centrioles are highly conserved structures throughout evolution. They are organized in a 9-fold symmetry of microtubule triplets. In animals, centrioles are building blocks of the centrosome. The centrosome is the main organizing center of microtubules and is necessary for fundamental processes such as cell division and polarity. Under specific conditions, the mother centriole is able to migrate and anchor to a cell membrane to build a cilium. The anchoring process involves the distal extremity of the mother centriole and in particular the distal appendages. During ciliogenesis, the mother centriole matures and is called the basal body. The distal appendages mature in transition fibers and determine the proximal extremity of the transition zone, which acts as a filter to ensure the specificity of the protein and lipid composition of the cilium. During evolution, the structure of cilia is highly conserved, despite variations between organisms have been observed. Cilia play an essential role in signaling and / or motility. Consequently, in humans, rare genetic diseases originate from ciliary defects causing poly-malformation syndromes called ciliopathies. During my thesis, I was interested in identifying new actors of basal bodies anchoring using two complementary models: human cell cultures and Paramecium Tetraurelia. The basal bodies in Paramecium are all anchored to the plasma membrane and did not display any centriolar stages. Consequently, in this organism, anchoring defects are characterized by the presence of easily observable non-anchored basal bodies. Using this model, members of the team have already characterized the involvement of 4 proteins in the basal bodies anchoring: Cen2, OFD1, FOPNL and Cen3. In human, FOPNL, OFD1 and MNR form a complex involved in ciliogenesis, MNR and OFD1 both being involved in ciliopathies. To The search of novel actors involved in the basal body anchoring process has been achieved using BioID, a proximity identification technic, using FOPNL as a bait. We determined that the CEP90 protein is localized in the close environment of FOPNL. In human cells, CEP90 shares the same localization as FOPNL and OFD1 at centrioles and centriolar satellites and is also involved in ciliopathy. Using a super-resolution imaging technique called expansion microscopy, we show that CEP90, FOPNL, and OFD1 are organized in 9-fold symmetry at the distal part of the centrioles and basal bodies, close to the distal appendage protein CEP83. The recruitment of CEP90, FOPNL and OFD1 at basal bodies is interdependent and the absence of one of these proteins leads to basal body anchoring defects in Paramecium. In mammals, the depletion of FOPNL or CEP90 affects the recruitment of 3 distal appendage proteins (CEP83, CEP89 and CEP164). In mammalian cells, we demonstrated that CEP90 and OFD1 are recruited during duplication on early born procentrioles and that the co-overexpression of MNR and CEP90 is sufficient to recruit OFD1 and CEP83 along the microtubule network. Altogether these results shed new light on the basal body anchoring process. In addition, the early recruitment of CEP90, FOPNL and OFD1 complex on newly born procentrioles led us to propose that the localization of the complex specify the future location of the distal appendages. Finally, in this thesis, we show that CEP90, FOPNL and OFD1 is functionally conserved from Paramecium to mammalian cells despite it is absent in some phyla such as Drosophila and C.elegans.Les centrioles sont des structures cellulaires trĂšs conservĂ©es au cours de lâĂ©volution. Ils sont organisĂ©s en symĂ©trie 9 de triplets de microtubules. Le centrosome est le principal centre organisateur des microtubules et est nĂ©cessaire pour assurer des processus fondamentaux tels que la division et la polaritĂ© cellulaire. Lorsque que les conditions le permettent, le centriole pĂšre est capable de migrer et de sâancrer Ă une membrane cellulaire pour former un cil. Le processus dâancrage fait intervenir la partie distale du centriole pĂšre et notamment les appendices distaux. Au cours de la ciliogenĂšse, le centriole pĂšre subit une maturation et est appelĂ© corps basal. Les appendices distaux forment les fibres de transition et dĂ©terminent la partie antĂ©rieure de la zone de transition qui joue un rĂŽle de filtre nĂ©cessaire pour assurer la spĂ©cificitĂ© de la composition protĂ©ique et lipidique du cil. Au cours de lâĂ©volution, la structure des cils est trĂšs conservĂ©e malgrĂ© lâobservation de variations structurales entre diffĂ©rents organismes. Les cils jouent un rĂŽle essentiel dans la signalisation et/ou de motilitĂ©. Par consĂ©quence, chez lâhomme, les dĂ©fauts ciliaires sont Ă lâorigine de maladies gĂ©nĂ©tiques rares causant des syndromes poly-malformatifs regroupĂ©s sous le nom de ciliopathies. Au cours de ma thĂšse je me suis intĂ©ressĂ© Ă identifier de nouveaux acteurs de lâancrage des corps basaux en utilisant deux modĂšles complĂ©mentaires : des cultures de cellules humaines et lâorganisme unicellulaire Paramecium Tetraurelia. Les corps basaux de la paramĂ©cie sont tous ancrĂ©s Ă la membrane plasmique sans passer par une Ă©tape centriolaire. Par consĂ©quence chez cet organisme des dĂ©fauts dâancrage se caractĂ©risent par la prĂ©sence de corps basaux non ancrĂ©s dans le cytoplasme et facilement observables. GrĂące Ă ce modĂšle les membres de lâĂ©quipe ont dĂ©jĂ caractĂ©risĂ©s lâimplication de 4 protĂ©ines dans lâancrage des corps basaux : Cen2, OFD1, FOPNL et Cen3. Chez lâhomme FOPNL, OFD1 et MNR forment un complexe nĂ©cessaire Ă la ciliogenĂšse, MNR et OFD1 Ă©tant toutes les deux impliquĂ©es dans des ciliopathies. Jâai recherchĂ© de nouveaux acteurs de lâancrage des corps basaux en rĂ©alisant une technique dâidentification par proximitĂ©, la BioID, en utilisant FOPNL comme appĂąt. Nous avons dĂ©terminĂ© que la protĂ©ine CEP90 est localisĂ©e dans lâenvironnement proche de FOPNL. Dans les cellules humaines, CEP90 partage la mĂȘme localisation que FOPNL et OFD1 aux centrioles et aux satellites centriolaires et est aussi impliquĂ©e dans des ciliopathies. En utilisant une technique dâimagerie super-rĂ©solutive appelĂ©e microscopie Ă expansion, nous montrons que CEP90, FOPNL et OFD1 sont organisĂ©es en symĂ©trie 9 en partie distale des centrioles et des corps basaux, proche de la protĂ©ine des appendices distaux CEP83. Le recrutement aux centrioles et corps basaux de CEP90, FOPNL et OFD1 est interdĂ©pendant et lâabsence dâune de ces protĂ©ines entraine des dĂ©fauts dâancrage des corps basaux chez la paramĂ©cie. Chez les mammifĂšre, la dĂ©plĂ©tion de FOPNL ou CEP90 affecte le recrutement de 3 protĂ©ines de appendices distaux (CEP83, CEP89 et CEP164) impliquĂ©es dans lâancrage des corps basaux. Dans les cellules de mammifĂšres, nous avons dĂ©montrĂ© que CEP90 et OFD1 sont recrutĂ©es trĂšs prĂ©cocement sur les procentrioles au cours de la duplication et que la co-surexpression de MNR et CEP90 est suffisante pour recruter OFD1 et CEP83 le long du rĂ©seau de microtubules. La surexpression de CEP90 seule forme des agrĂ©gats capables de recruter OFD1 et CEP83. Lâensemble de ces rĂ©sultats apporte un Ă©clairage nouveau sur le processus dâancrage des corps basaux. Le recrutement prĂ©coce du complexe CEP90, FOPNL et OFD1 nous a conduit Ă proposer que ce complexe permettait de spĂ©cifier la future localisation des appendices distaux. Enfin, dans cette thĂšse nous montrons que le complexe CEP90, FOPNL et OFD1 est fonctionnellement conservĂ© chez la paramĂ©cie et les cellules de mammifĂšres
Prise en charge des cystites aiguës simples aux urgences (adhérence aux recommandations françaises de l ANSM (2008))
PARIS7-Xavier Bichat (751182101) / SudocSudocFranceF
La paramécie, un organisme modÚle pour étudier la ciliogenÚse et les maladies ciliaires
International audienceLe cil est une extension prĂ©sente Ă la surface de la quasi-totalitĂ© des cellules eucaryotes. ConservĂ© au cours de lâĂ©volution, il assure des fonctions sensorielles et/ou motiles. Chez lâhomme, le dysfonctionnement ciliaire est Ă lâorigine de diffĂ©rentes maladies regroupĂ©es sous le nom de ciliopathies. GrĂące Ă sa ciliature complexe, la paramĂ©cie constitue un modĂšle de choix pour Ă©tudier non seulement la structure, lâassemblage et les fonctions des cils, mais aussi pour valider les mutations de gĂšnes associĂ©es Ă ces ciliopathies
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