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Ferreira, T.

Publications and source records attributed to Ferreira, T..

At least 19 recordsLinked to original sources

Molecular determinants of low affinity complexes formed by the electrical synapse proteins Connexin36 (Cx36) and ZO-1

Although chemical and electrical synapses function fundamentally differently, they evidently share common design principles. Like neurotransmitter receptors, Connexin 36 (Cx36) containing gap junction channels, key constituents of electrical synapses, are anchored to scaffolding proteins that stabilize the connexin at the synapse. One of the most prominent proteins that has been described in this context is the Zonula occludens protein 1 (ZO-1). ZO-1 interacts with Cx36 via one of its three PDZ domains. This interaction is inherently weak and was suggested to facilitate the dynamic regulation of electrical synapses. In the present study, we have combined Gaussian accelerated molecular dynamics simulations and binding assays to identify the exact residues in the PDZ binding motif of Cx36 that are necessary to sustain these low affinity interactions. Among the different Cx36 mutations we have generated, we discovered a single substitution at position 319 within the PDZ binding motif that massively increases binding in different experimental settings. In addition to this site, we found that acidic residues adjacent to the PDZ binding motif (PBM) in Cx36 and its fish orthologues are evolutionarily tuned to weaken PDZ interactions as well. We were able to enhance PDZ1 binding drastically by substituting these residues with hydrophobic or positively charged amino acids. Finally, we demonstrate that the weak PDZ1/Cx36 interaction is sensitive to CaMKII mediated phosphorylation of Cx36, suggesting that ZO-1 unbinding may be a necessary event to potentiate electrical synapses. In summary, our study provides a detailed analysis of different mechanisms that can be exploited to modify the interaction between two key components of an electrical synapse: Cx36 and ZO-1.

biochemistry↗

Absence of Telomerase Leads to Immune Response and Tumor Regression in Zebrafish Melanoma

Most cancers reactivate telomerase to maintain telomere length to acquire immortality. The importance of this process is well illustrated by the fact that telomerase promoter mutations are found at a high frequency in many cancer types, including melanoma. However, it is unclear when and if telomerase is strictly required during tumorigenesis. Here, we show that melanoma can occur in the absence of telomerase but is required to sustain later growth and to avoid tumor regression. We combined telomerase mutant zebrafish (tert-/-) with two established melanoma models and found equal melanoma incidence and invasiveness as tumors became visible. Later, however, while tert+/+ fish develop increasing larger tumors, tert-/- tumors stagnate growth and regress. tert-/- tumors showed lower cell proliferation, higher apoptosis and melanocyte differentiation. We also detected an immune response directed at tert-/- tumors. tert-/- tumors exhibited increased immune cell infiltrates and resume growth when transplanted into immunocompromised hosts. We propose that telomerase is required for melanoma in zebrafish, albeit at later stages of progression, to sustain growth while avoiding immune rejection and regression. Thus, absence of telomerase restricts melanoma through tumor-autonomous mechanisms (cell cycle arrest, apoptosis and melanocyte differentiation) and a non-tumor-autonomous mechanisms (immune rejection).

cancer biology↗

A Saturated Map of Common Genetic Variants Associated with Human Height from 5.4 Million Individuals of Diverse Ancestries

Common SNPs are predicted to collectively explain 40-50% of phenotypic variation in human height, but identifying the specific variants and associated regions requires huge sample sizes. Here we show, using GWAS data from 5.4 million individuals of diverse ancestries, that 12,111 independent SNPs that are significantly associated with height account for nearly all of the common SNP-based heritability. These SNPs are clustered within 7,209 non-overlapping genomic segments with a median size of ~90 kb, covering ~21% of the genome. The density of independent associations varies across the genome and the regions of elevated density are enriched for biologically relevant genes. In out-of-sample estimation and prediction, the 12,111 SNPs account for 40% of phenotypic variance in European ancestry populations but only ~10%-20% in other ancestries. Effect sizes, associated regions, and gene prioritization are similar across ancestries, indicating that reduced prediction accuracy is likely explained by linkage disequilibrium and allele frequency differences within associated regions. Finally, we show that the relevant biological pathways are detectable with smaller sample sizes than needed to implicate causal genes and variants. Overall, this study, the largest GWAS to date, provides an unprecedented saturated map of specific genomic regions containing the vast majority of common height-associated variants.

genetics↗

The kpc-1 (furin) 3'UTR promotes dendritic transport and local translation of mRNAs to regulate dendrite branching and self-avoidance of a nociceptive neuron

A recently reported Schizophrenia-associated genetic variant in the 3UTR of the human furin gene, a homolog of C. elegans kpc-1, highlights an important role of the furin 3UTR in neuronal development(1). We isolate three kpc-1 mutants that display abnormal dendrite arborization in PVD neurons and defective male mating behaviors. We show that the kpc-1 3UTR participates in dendrite branching and self-avoidance. The kpc-1 3UTR facilitates mRNA localization to branching points and contact points between sibling dendrites and promotes local protein synthesis. We identify a secondary structural motif in the kpc-1 3UTR required for dendrite self-avoidance. Animals with dma-1 receptor over-expression exhibit similar dendrite branching and self-avoidance defects that are suppressed with kpc-1 over-expression. Our results support a model in which KPC-1 proteins are synthesized at branching points and contact points to locally down-regulate DMA-1 receptors to promote dendrite branching and self-avoidance of a mechanosensory neuron important for male courtship.

neuroscience↗

Lysophophatidyl-choline 16:0 mediates persistent joint pain through Acid-Sensing Ion Channel 3: preclinical and clinical evidences

Rheumatic diseases are often associated to debilitating chronic joint pain, which remains difficult to treat and requires new therapeutic strategies. Here, we describe increased content of lysophosphatidyl-choline (LPC) 16:0 in the knee synovial fluids of two independent cohorts of patients with painful joint diseases. If LPC16:0 levels correlated with pain in patients with osteoarthritis (OA), they do not appear to be the hallmark of a particular joint disease. We found that intra-articular injections of LPC16:0 in mouse produce chronic pain and anxiety-like behaviors in both males and females with no apparent inflammation, peripheral nerve sprouting and damage, nor bone alterations. LPC16:0-induced persistent pain state is dependent on peripheral Acid-Sensing Ion Channel 3 (ASIC3), ultimately leading to central sensitization. LPC16:0 and ASIC3 thus appear as key players of chronic joint pain with potential implications in OA and possibly across others rheumatic diseases.

neuroscience↗

Environment and sex control lifespan and telomere length in wild-derived African killifish

Telomere length is correlated positively with longevity at the individual level, but negatively when compared across species. Here, we tested the association between lifespan and telomere length in African annual killifish. We analyzed telomere length in 18 Nothobranchius strains derived from diverse habitats and measured the laboratory lifespan of 14 strains of N. furzeri and N. kadleci. We found that males had shorter telomeres than females. The longest telomeres were recorded in strains derived from dry region where male lifespans were shortest. At the individual level, we detected a weak negative association between rapid juvenile growth and shorter telomeres in early adulthood. Overall, average telomere length was a good descriptor of telomere length distribution. However, within-individual telomere length spread was not related to any pattern. This substantial variation in telomere length between strains from different environments provides killifish as powerful tool to understand the evolutionarily adaptive value of telomere length.

evolutionary biology↗

Polyunsaturated phospholipids increase cell resilience to mechanical constraints

Despite the fact that PolyUnsaturated Fatty Acids (PUFA) are generally accepted to be good for health, the mechanisms of their bona fide benefits still remain elusive. PUFA are particularly enriched in the membrane Phospholipids (PLs) of selective organs, among which skeletal muscles and the cardiovascular system are prime examples. The fatty acid composition of PLs is known to regulate crucial membrane properties, including rigidity, elasticity and plasticity. Since muscle cells undergo repeated cycles of elongation and relaxation and are constantly exposed to mechanical stress, we postulated in the present study that PUFA-containing PLs could be central players for muscle cell adaptation to mechanical constraints. By a combination of in cellulo and in silico approaches, we show that PUFA, and particularly the {omega}-3 DocoHexaenoic Acid (DHA), regulate important properties of the plasma membrane that improve muscle cell resilience to mechanical constraints. Thanks to their unique property to contortionate within the bilayer plane, they facilitate the formation of Vacuole-like dilation (VLD) which, in turn, reduce membrane stress and avoid cell breakage under mechanical constraints.

cell biology↗

A comprehensive study of Phospholipid fatty acid rearrangements in the early onset of the metabolic syndrome: correlations to organ dysfunction.

The balance within phospholipids (PL) between Saturated Fatty Acids (SFA) and mono- or poly-Unsaturated Fatty Acids (UFA), is known to regulate the biophysical properties of cellular membranes. As a consequence, perturbating this balance alters crucial cellular processes in many cell types, such as vesicular budding and the trafficking/function of membrane-anchored proteins. The worldwide spreading of the Western-diet, which is specifically enriched in saturated fats, has been clearly correlated with the emergence of a complex syndrome, known as the Metabolic Syndrome (MetS), which is defined as a cluster of risk factors for cardiovascular diseases, type 2 diabetes and hepatic steatosis. However, no clear correlations between diet-induced fatty acid redistribution within cellular PL, the severity/chronology of the symptoms associated to MetS and the function of the targeted organs, particularly in the early onset of the disease, have been established. In an attempt to fill this gap, we analyzed in the present study PL remodeling in rats exposed during 15 weeks to a High Fat/High Fructose diet (HFHF) in several organs, including known MetS targets. We show that fatty acids from the diet can distribute within PL in a very selective way, with PhosphatidylCholine being the preferred sink for this distribution. Moreover, in the HFHF rat model, most organs are protected from this redistribution, at least during the early onset of MetS, at the exception of the liver and skeletal muscles. Interestingly, such a redistribution correlates with clear-cut alterations in the function of these organs.

biochemistry↗

The genetic architecture of sporadic and recurrent miscarriage

Miscarriage is a common complex trait that affects 10-25% of clinically confirmed pregnancies1,2. Here we present the first large-scale genetic association analyses with 69,118 cases from five different ancestries for sporadic miscarriage and 750 cases of European ancestry for recurrent miscarriage, and up to 359,469 female controls. We identify one genome-wide significant association on chromosome 13 (rs146350366, minor allele frequency (MAF) 1.2%, Pmeta=3.2x -8 (CI) 1.2-1.6) for sporadic miscarriage in our European ancestry meta-analysis (50,060 cases and 174,109 controls), located near FGF9 involved in pregnancy maintenance3 and progesterone production4. Additionally, we identified three genome-wide significant associations for recurrent miscarriage, including a signal on chromosome 9 (rs7859844, MAF=6.4%, Pmeta=1.3x -8 in controlling extravillous trophoblast motility5. We further investigate the genetic architecture of miscarriage with biobank-scale Mendelian randomization, heritability and, genetic correlation analyses. Our results implicate that miscarriage etiopathogenesis is partly driven by genetic variation related to gonadotropin regulation, placental biology and progesterone production.

genetics↗

Anthropogenic Soils Promote Biodiversity in Amazonian Rainforests

Amazonian Dark Earths (ADEs) are fertile anthropic soils found throughout Amazonia, resulting from long-term occupation by pre-Columbian societies. Although the chemistry of these soils is well known, their biodiversity, particularly soil invertebrate communities have been neglected. To address this, we characterised soil macroinvertebrate communities and their activities in ADEs, comparing them with adjacent reference soils under forests and agriculture, at nine archaeological sites. We found 667 morphospecies and a tenacious pre-Columbian biodiversity footprint, with 40% of species found exclusively in ADEs. Soil biological activity was higher in ADEs than in adjacent soils, and associated with higher biomass and richness of organisms known to engineer the ecosystem. We show that these habitats have unique species pools, but that contemporary land-use causes nutrient loss and threatens their diversity. Both past and present human activities alter biodiversity and its distribution in Amazonia, and further efforts are needed to recognize and preserve these ADEs and their biodiversity.

zoology↗

Lifelong genetically lowered sclerostin and risk of cardiovascular disease.

BackgroundInhibition of sclerostin is a novel therapeutic approach to lowering fracture risk. However, phase III randomised controlled trials (RCTs) of romosozumab, a monoclonal antibody that inhibits sclerostin, suggest an imbalance of serious cardiovascular events. MethodsWe used two independent genetic variants (rs7209826 and rs188810925) in SOST (encoding sclerostin) associated with bone mineral density (BMD) as proxies for therapeutic inhibition of sclerostin. We estimated the effects on risk of osteoporosis, fracture, coronary heart disease (CHD) and a further 22 cardiometabolic risk factors and diseases, by combining data from up to 478,967 participants of European ancestry from three prospective cohorts and up to 1,030,836 participants from nine GWAS consortia. In addition, we performed meta-analyses of cardiovascular outcome data from phase III RCTs of romosozumab. ResultsMeta-analysis of RCTs identified a higher risk of cardiac ischemic events in patients randomised to romosozumab (25 events among 4,298 individuals; odds ratio [OR] 2{middle dot}98; 95% confidence interval [CI], 1{middle dot}18 to 7{middle dot}55; P=0{middle dot}017). Scaled to the equivalent dose of romosozumab (210mg/month; 0{middle dot}09 g/cm2 higher BMD), the SOST variants associated with lower risk of fracture (OR, 0{middle dot}59; 95% CI, 0{middle dot}54-0{middle dot}66; P= 1{middle dot}4x10-24), and osteoporosis (OR, 0{middle dot}43; 95% CI, 0{middle dot}36-0{middle dot}52; P=2{middle dot}4x10-18). The SOST variants associated with higher risk of myocardial infarction and/or coronary revascularisation (69,649 cases; OR, 1{middle dot}18; 95% CI, 1{middle dot}06-1{middle dot}32; P=0{middle dot}003) and type 2 diabetes (OR 1{middle dot}15; 95% CI, 1{middle dot}05-1{middle dot}27; P=0{middle dot}003), higher systolic blood pressure (1{middle dot}3mmHg; 95% CI 0{middle dot}8-1{middle dot}9; P=5{middle dot}9x10-6) and waist-to-hip-ratio adjusted for BMI (0{middle dot}05 SDs; 95% CI, 0{middle dot}02 to 0{middle dot}08; P=8{middle dot}5x10-4). ConclusionsGenetically and therapeutically lowered sclerostin leads to higher risk of cardiovascular events. Rigorous evaluation of the cardiovascular safety of romosozumab and other sclerostin inhibitors is warranted.

genetics↗

Causal relevance of obesity on the leading causes of death in women and men: A Mendelian randomization study

BackgroundObesity traits are causally implicated with risk of cardiometabolic diseases. It remains unclear whether there are similar causal effects of obesity traits on other non-communicable diseases. Also, it is largely unexplored whether there are any sex-specific differences in the causal effects of obesity traits on cardiometabolic diseases and other leading causes of death. We therefore tested associations of sex-specific genetic risk scores (GRSs) for body mass index (BMI), waist-hip-ratio (WHR), and WHR adjusted for BMI (WHRadjBMI) with leading causes of mortality, using a Mendelian randomization (MR) framework. Methods and FindingsWe constructed sex-specific GRSs for BMI, WHR, and WHRadjBMI, including 565, 324, and 338 genetic variants, respectively. These GRSs were then used as instrumental variables to assess associations between the obesity traits and leading causes of mortality using an MR design in up to 422,414 participants from the UK Biobank. We also investigated associations with potential mediators and risk factors, including smoking, glycemic and blood pressure traits. Sex-differences were subsequently assessed by Cochrans Q-test (Phet). Up to 227,717 women and 194,697 men with mean (standard deviation) age 56.6 (7.9) and 57.0 (8.1) years, body mass index 27.0 (5.1) and 27.9 (4.2) kg/m2 and waist-hip-ratio 0.82 (0.07) and 0.94 (0.07), respectively, were included. Mendelian randomization analysis showed that obesity causes coronary artery disease, stroke (particularly ischemic), chronic obstructive pulmonary disease, lung cancer, type 2 and 1 diabetes mellitus, non-alcoholic fatty liver disease, chronic liver disease, and acute and chronic renal failure. A 1 standard deviation higher body mass index led to higher risk of type 2 diabetes in women (OR 3.81; 95% CI 3.42-4.25, P=8.9x10-130) than in men (OR 2.78; 95% CI 2.57-3.02, P=1.0x10-133, Phet=5.1x10-6). Waist-hip-ratio led to a higher risk of chronic obstructive pulmonary disease (Phet=5.5x10-6) and higher risk of chronic renal failure (Phet=1.3x10-4) in men than women. A limitation of MR studies is potential bias if the genetic variants are directly associated with confounders (pleiotropy), but sensitivity analyses such as MR-Egger supported the main findings. Our study was also limited to people of European descent and results may differ in people of other ancestries. ConclusionsObesity traits have an etiological role in the majority of the leading global causes of death. Sex differences exist in the effects of obesity traits on risk of type 2 diabetes, chronic obstructive pulmonary disease, and renal failure, which may have implications on public health.

epidemiology↗

Restoration of visual function by transplantation of optogenetically engineered photoreceptors

A major challenge in the treatment of retinal degenerative diseases, with the transplantation of replacement photoreceptors, is the difficulty in inducing the grafted cells to grow and maintain light sensitive outer segments (OS) in the host retina, which depends on proper interaction with the underlying retinal pigment epithelium (RPE). For a RPE-independent treatment approach, we introduced a hyperpolarizing microbial opsin into photoreceptor precursors from new-born mice, and transplanted them into blind mice lacking the photoreceptor layer. These optogenetically transformed photoreceptors were light responsive and their transplantation lead to the recovery of visual function, as shown by ganglion cell recordings and behavioral tests. Subsequently, we generated cone photoreceptors from human induced pluripotent stem cells (hiPSCs), expressing the chloride pump Jaws. After transplantation into blind mice, we observed light-driven responses at the photoreceptor and ganglion cell level. These results demonstrate that structural and functional retinal repair is possible by combining stem cell therapy and optogenetics.

bioengineering↗

GWAS meta-analysis highlights the hypothalamic-pituitary-gonadal axis (HPG axis) in the genetic regulation of menstrual cycle length

The normal menstrual cycle requires a delicate interplay between the hypothalamus, pituitary, and ovary. Therefore, its length is an important indicator of female reproductive health. Menstrual cycle length has been shown to be partially controlled by genetic factors, especially in the follicle stimulating hormone beta-subunit (FSHB) locus. GWAS meta-analysis of menstrual cycle length in 44,871 women of European ancestry confirmed the previously observed association with the FSHB locus and identified four additional novel signals in, or near, the GNRH1, PGR, NR5A2 and INS-IGF2 genes. These findings confirm the role of the hypothalamic-pituitary-gonadal axis in the genetic regulation of menstrual cycle length, but also highlight potential novel local regulatory mechanisms, such as those mediated by IGF2.

genetics↗

Genome-wide association analysis identifies 27 novel loci associated with uterine leiomyomata revealing common genetic origins with endometriosis

Uterine leiomyomata (UL), also known as uterine fibroids, are the most common neoplasms of the reproductive tract and the primary cause for hysterectomy, leading to considerable impact on womens lives as well as high economic burden1,2. Genetic epidemiologic studies indicate that heritable risk factors contribute to UL pathogenesis3. Previous genome-wide association studies (GWAS) identified five loci associated with UL at genome-wide significance (P < 5 x 10-8)4-6. We conducted GWAS meta-analysis in 20,406 cases and 223,918 female controls of white European ancestry, identifying 24 genome-wide significant independent loci; 17 replicated in an unrelated cohort of 15,068 additional cases and 43,587 female controls. Aggregation of discovery and replication studies (35,474 cases and 267,505 female controls) revealed six additional significant loci. Interestingly, four of the 17 loci identified and replicated in these analyses have also been associated with risk for endometriosis - another common gynecologic disorder. These findings increase our understanding of the biological mechanisms underlying UL development, and suggest overlapping genetic origins with endometriosis.

genomics↗

Meta-analysis of genome-wide association studies for body fat distribution in 694,649 individuals of European ancestry

One in four adults worldwide are either overweight or obese. Epidemiological studies indicate that the location and distribution of excess fat, rather than general adiposity, is most informative for predicting risk of obesity sequellae, including cardiometabolic disease and cancer. We performed a genome-wide association study meta-analysis of body fat distribution, measured by waist-to-hip ratio adjusted for BMI (WHRadjBMI), and identified 463 signals in 346 loci. Heritability and variant effects were generally stronger in women than men, and we found approximately one-third of all signals to be sexually dimorphic. The 5% of individuals carrying the most WHRadjBMI-increasing alleles were 1.62 times more likely than the bottom 5% to have a WHR above the thresholds used for metabolic syndrome. These data, made publicly available, will inform the biology of body fat distribution and its relationship with disease.

genetics↗

GWAS identifies novel risk locus for erectile dysfunction and implicates hypothalamic neurobiology and diabetes in etiology

GWAS of erectile dysfunction (ED) in 6,175 cases among 223,805 European men identified one new locus at 6q16.3 (lead variant rs57989773, OR 1.20 per C-allele; p = 5.71x10-14), located between MCHR2 and SIM1. In-silico analysis suggests SIM1 to confer ED risk through hypothalamic dysregulation; Mendelian randomization indicates genetic risk of type 2 diabetes causes ED. Our findings provide novel insights into the biological underpinnings of ED.

genomics↗

GWAS identifies 10 loci for objectively-measured physical activity and sleep with causal roles in cardiometabolic disease.

Physical activity and sleep disorders are established risk factors for many diseases, but their etiology is poorly understood, partly due to a reliance on self-reported evidence. Here we report a genome-wide association study (GWAS) of wearable-defined and machine-learned physical activity and sleep phenotypes in 91,112 UK Biobank participants, and self-reported physical activity in 351,154 UK Biobank participants. While the self-reported activity analysis resulted in no significant (p<5x10-9) loci, the analysis of objectively-measured traits identified 10 loci, 6 of which are novel. These 10 loci account for 0.05% of activity and 0.33% of sleep phenotype variation, but genome-wide estimates suggest that common variation accounts for ~12% of phenotypic variation, indicating high polygenicity. Heritability was higher in women than in men for overall activity ({Delta}h2 = 4%, p=6.3x10-5), moderate intensity activity (6%, p=6.7x10-8), and walking (5%, p=2.6x10-6). Heritability partitioning, enrichment and pathway analyses all indicate the central nervous system plays a role in activity behaviours. Mendelian randomization in publicly available GWAS data and in 278,367 UK Biobank participants, who were not included in our discovery analyses, suggest that overall activity might be causally related to lowering body fat percentage (beta per SD higher overall activity: -0.44, SE=0.047, p=2.70x10-21) and systolic blood pressure (beta per SD: -0.71, SE=0.125, p=1.38x10-8). Our current results advocate the value of physical activity for the reduction of adiposity and blood pressure.

genetics↗