Despite numerous studies on fetal therapy for myelomeningoceles (MMC), the pathophysiology of this malformation remains poorly understood. This study aimed to analyze the biochemical profile and proteome of amniotic fluid (AF) supernatants from MMC fetuses to explore the prenatal pathophysiology. Biochemical analysis of 61 AF samples from MMC fetuses was compared with 45 healthy fetuses' samples.
View Article and Find Full Text PDFAlternative transcription start site (TSS) usage regulation has been identified as a major means of gene expression regulation in metazoans. However, in fungi, its impact remains elusive as its study has thus far been restricted to model yeasts. Here, we first re-analyzed TSS-seq data to define genuine TSS clusters in 2 species of pathogenic Cryptococcus.
View Article and Find Full Text PDFTuning of protein homeostasis through mobilization of the unfolded protein response (UPR) is key to the capacity of pancreatic beta cells to cope with variable demand for insulin. Here, we asked how insulin-degrading enzyme (IDE) affects beta cell adaptation to metabolic and immune stress. C57BL/6 and autoimmune non-obese diabetic (NOD) mice lacking IDE were exposed to proteotoxic, metabolic, and immune stress.
View Article and Find Full Text PDFMutations in the gene are the most common cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The pathogenetic mechanisms linked to this gene are a direct consequence of an aberrant intronic expansion of a GGGGCC hexanucleotide located between the 1a and 1b non-coding exons, which can be transcribed to form cytotoxic RNA foci or even translated into aggregation-prone dipeptide repeat proteins. Importantly, the abnormal length of these repeats affects also the expression levels of C9orf72 itself, which suggests haploinsufficiency as additional pathomechanism.
View Article and Find Full Text PDFFocal and segmental glomerulosclerosis (FSGS) is a severe form of idiopathic nephrotic syndrome (INS), a glomerulopathy of presumably immune origin that is attributed to extrarenal pathogenic circulating factors. The recurrence of FSGS (rFSGS) after transplant occurs in 30% to 50% of cases. The direct analysis of patient plasma proteome has scarcely been addressed to date, mainly due to the methodological difficulties associated with plasma complexity and dynamic range.
View Article and Find Full Text PDFAppropriate tuning of protein homeostasis through mobilization of the unfolded protein response (UPR) is key to the capacity of pancreatic beta cells to cope with highly variable demand for insulin synthesis. An efficient UPR ensures a sufficient beta cell mass and secretory output but can also affect beta cell resilience to autoimmune aggression. The factors regulating protein homeostasis in the face of metabolic and immune challenges are insufficiently understood.
View Article and Find Full Text PDFInsulin-degrading enzyme (IDE) is a highly conserved metalloprotease that is mainly localized in the cytosol. Although IDE can degrade insulin and some other low molecular weight substrates efficiently, its ubiquitous expression suggests additional functions supported by experimental findings, such as a role in stress responses and cellular protein homeostasis. The translation of a long full-length IDE transcript has been reported to result in targeting to mitochondria, but the role of IDE in this compartment is unknown.
View Article and Find Full Text PDFBiolayer interferometry (BLI) is a technology which allows to study the affinity between two interacting macro-molecules and to visualize their kinetic of interaction in real time. In this work, we combine BLI interaction measurement with mass spectrometry in order to identify the proteins interacting with the bait. We provide for the first time the proof of concept of the feasibility of BLI-MS in complex biological mixtures.
View Article and Find Full Text PDFAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease, which is still missing effective therapeutic strategies. Although manipulation of neuronal excitability has been tested in murine and human ALS models, it is still under debate whether neuronal activity might represent a valid target for efficient therapies. In this study, we exploited a combination of transcriptomics, proteomics, optogenetics and pharmacological approaches to investigate the activity-related pathological features of iPSC-derived C9orf72-mutant motoneurons (MN).
View Article and Find Full Text PDFFollicle-stimulating hormone (FSH) is a glycohormone synthesized by adenohypophysis, and it stimulates ovulation in women and spermatogenesis in men by binding to its receptor (FSHR). FSHR is involved in several mechanisms to transduce intracellular signals in response to the FSH stimulus. Exogenous FSH is currently used in the clinic for ovarian hyperstimulation during in vitro fertilization in women, and for treatment of infertility caused by gonadotropin deficiency in men.
View Article and Find Full Text PDFFront Cell Infect Microbiol
July 2021
The high prevalence of sickle cell disease in some human populations likely results from the protection afforded against severe malaria and death by heterozygous carriage of HbS. remodels the erythrocyte membrane and skeleton, displaying parasite proteins at the erythrocyte surface that interact with key human proteins in the Ankyrin R and 4.1R complexes.
View Article and Find Full Text PDFVAMP7 is involved in autophagy and in exocytosis-mediated neurite growth, two yet unconnected cellular pathways. Here, we find that nutrient restriction and activation of autophagy stimulate axonal growth, while autophagy inhibition leads to loss of neuronal polarity. VAMP7 knockout (KO) neuronal cells show impaired neurite growth, whereas this process is increased in autophagy-null ATG5 KO cells.
View Article and Find Full Text PDFMethylmalonic acidemia is a rare inborn error of metabolism with severe clinical complications and poor outcome. The present data article is related to a proteomic investigation conducted on a HEK 293 cell line which has been genetically modified using CRISPR-CAS9 system to knockout the methylmalonyl-CoA mutase enzyme (MUT-KO). Thus, the generated cell model for methylmalonic acidemia was used for a proteomic comparison with respect to HEK 293 wild type cells performing a label-free quantification (LFQ) experiment.
View Article and Find Full Text PDFThe analysis of T cell lipid raft proteome is challenging due to the highly dynamic nature of rafts and the hydrophobic character of raft-resident proteins. We explored an innovative strategy for bottom-up lipid raftomics based on suspension-trapping (S-Trap) sample preparation. Mouse T cells were prepared from splenocytes by negative immunoselection, and rafts were isolated by a detergent-free method and OptiPrep gradient ultracentrifugation.
View Article and Find Full Text PDFMethylmalonic acidemia (MMA) is a rare inborn error of metabolism caused by deficiency of the methylmalonyl-CoA mutase (MUT) enzyme. Downstream MUT deficiency, methylmalonic acid accumulates together with toxic metabolites from propionyl-CoA and other compounds upstream of the block in the enzyme pathway. The presentation is with life-threatening acidosis, respiratory distress, brain disturbance, hyperammonemia, and ketosis.
View Article and Find Full Text PDFSTK38 (also known as NDR1) is a Hippo pathway serine/threonine protein kinase with multifarious functions in normal and cancer cells. Using a context-dependent proximity-labeling assay, we identify more than 250 partners of STK38 and find that STK38 modulates its partnership depending on the cellular context by increasing its association with cytoplasmic proteins upon nutrient starvation-induced autophagy and with nuclear ones during ECM detachment. We show that STK38 shuttles between the nucleus and the cytoplasm and that its nuclear exit depends on both XPO1 (aka exportin-1, CRM1) and STK38 kinase activity.
View Article and Find Full Text PDFProper brain development relies highly on protein N-glycosylation to sustain neuronal migration, axon guidance and synaptic physiology. Impairing the N-glycosylation pathway at early steps produces broad neurological symptoms identified in congenital disorders of glycosylation. However, little is known about the molecular mechanisms underlying these defects.
View Article and Find Full Text PDFUnlabelled: Cystic fibrosis (CF) and primary ciliary dyskinesia (PCD) are pulmonary genetic disorders associated with inflammation and heterogeneous progression of the lung disease. We hypothesized that respiratory exosomes, nanovesicles circulating in the respiratory tract, may be involved in the progression of inflammation-related lung damage. We compared proteomic content of respiratory exosomes isolated from bronchoalveolar lavage fluid in CF and PCD to asthma (A), a condition also associated with inflammation but with less severe lung damage.
View Article and Find Full Text PDFPreproghrelin is a prohormone producing several preproghrelin-derived peptides with structural and functional heterogeneity: acyl ghrelin (AG), desacyl ghrelin (DAG), and obestatin. The absence of selective and reliable assays to measure these peptides simultaneously in biological samples has been a limitation to assess their real proportions in tissues and plasma in physiological and pathological conditions. We aimed at reliably measure the ratio between the different preproghrelin-derived peptides in murine tissues using selective immunoassays combined with a highly sensitive mass spectrometry method.
View Article and Find Full Text PDFOld long-lived proteins contain dehydroalanine (Dha) and dehydrobutyrine (Dhb), two amino acids engendered by dehydration of serines and threonines, respectively. Although these residues have a suspected role in protein cross-linking and aggregation, their direct implication has yet to be determined. Here, we have taken advantage of the ability of the enteropathogen to convert the phosphothreonine residue of the pT--pY consensus sequence of ERK and p38 into Dhb and followed the impact of dehydration on the fate of the two MAPKs.
View Article and Find Full Text PDFCystinosis is a rare autosomal recessive lysosomal storage disorder characterized by intralysosomal accumulation of cystine. The causative gene for cystinosis is , which encodes the protein cystinosin, a lysosomal proton-driven cystine transporter. Over 100 mutations have been reported, leading to varying disease severity, often in correlation with residual cystinosin activity as a transporter and with maintenance of its protein-protein interactions.
View Article and Find Full Text PDFCell populations with differing proliferative, stem-like and tumorigenic states co-exist in most tumors and especially malignant gliomas. Whether metabolic variations can drive this heterogeneity by controlling dynamic changes in cell states is unknown. Metabolite profiling of human adult glioblastoma stem-like cells upon loss of their tumorigenicity revealed a switch in the catabolism of the GABA neurotransmitter toward enhanced production and secretion of its by-product GHB (4-hydroxybutyrate).
View Article and Find Full Text PDFCystic fibrosis (CF) is a genetic disease due to mutations in the cystic fibrosis transmembrane regulator (CFTR), F508del-CFTR being the most frequent. Lipid raft-like microdomains (LRM) are regions of the plasma membrane that present a high cholesterol content and are insoluble to non-ionic detergents. LRM are essential functional and structural platforms that play an important role in the inflammatory response.
View Article and Find Full Text PDFUnlabelled: We have previously shown (i) that the cystic fibrosis transmembrane regulator (CFTR) locates to lipid raft-like microdomains of epithelial cells upon TNF-α proinflammatory stimulation; and (ii) that TNF-α increases the membrane localization and the channel function of F508del-mutated CFTR. In the present work, we hypothesized that CFTR mutations modify the proteome of lipid rafts in the same proinflammatory conditions. We prepared lipid rafts from HeLa cells transfected with either wild-type or F508del-CFTR and incubated for 10min with 100U/mL of TNF-α.
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