RESUMO
Transposable elements constitute one of the main components of eukaryotic genomes. In vertebrates, they differ in content, typology, and family diversity and played a crucial role in the evolution of this taxon. However, due to their transposition ability, TEs can be responsible for genome instability, and thus silencing mechanisms were evolved to allow the coexistence between TEs and eukaryotic host-coding genes. Several papers are highlighting in TEs the presence of regulatory elements involved in regulating nearby genes in a tissue-specific fashion. This suggests that TEs are not sequences merely to silence; rather, they can be domesticated for the regulation of host-coding gene expression, permitting species adaptation and resilience as well as ensuring human health. This review presents the main silencing mechanisms acting in vertebrates and the importance of exploiting these mechanisms for TE control to rewire gene expression networks, challenging the general view of TEs as threatening elements.
Assuntos
Adaptação Biológica , Elementos de DNA Transponíveis , Inativação Gênica , Vertebrados , Elementos de DNA Transponíveis/fisiologia , Adaptação Biológica/genética , Vertebrados/genética , Vertebrados/fisiologia , AnimaisRESUMO
TEs are known to be among the main drivers in genome evolution, leading to the generation of evolutionary advantages that favor the success of organisms. The aim of this work was to investigate the TE landscape in bird genomes to look for a possible relationship between the amount of specific TE types and environmental changes that characterized the Oligocene era in Australia. Therefore, the mobilome of 29 bird species, belonging to a total of 11 orders, was analyzed. Our results confirmed that LINE retroelements are not predominant in all species of this evolutionary lineage and highlighted an LTR retroelement dominance in species with an Australian-related evolutionary history. The bird LTR retroelement expansion might have happened in response to the Earth's dramatic climate changes that occurred about 30 Mya, followed by a progressive aridification across most of Australian landmasses. Therefore, in birds, LTR retroelement burst might have represented an evolutionary advantage in the adaptation to arid/drought environments.
Assuntos
Evolução Molecular , Retroelementos , Animais , Retroelementos/genética , Filogenia , Austrália , Aves/genéticaRESUMO
Fish are an interesting taxon comprising species adapted to a wide range of environments. In this work, we analyzed the transcriptional contribution of transposable elements (TEs) in the gill transcriptomes of three fish species exposed to different salinity conditions. We considered the giant marbled eel Anguilla marmorata and the chum salmon Oncorhynchus keta, both diadromous, and the marine medaka Oryzias melastigma, an euryhaline organism sensu stricto. Our analyses revealed an interesting activity of TEs in the case of juvenile eels, commonly adapted to salty water, when exposed to brackish and freshwater conditions. Moreover, the expression assessment of genes involved in TE silencing mechanisms (six in heterochromatin formation, fourteen known to be part of the nucleosome remodeling deacetylase (NuRD) complex, and four of the Argonaute subfamily) unveiled that they are active. Finally, our results evidenced for the first time a krüppel-associated box (KRAB)-like domain specific to actinopterygians that, together with TRIM33, might allow the functioning of NuRD complex also in fish species. The possible interaction between these two proteins was supported by structural prediction analyses.
Assuntos
Oncorhynchus keta , Oryzias , Animais , Elementos de DNA Transponíveis/genética , Água Doce , Brânquias/metabolismo , Oncorhynchus keta/genética , Oryzias/genética , SalinidadeRESUMO
Since their identification as genomic regulatory elements, Transposable Elements (TEs) were considered, at first, molecular parasites and later as an important source of genetic diversity and regulatory innovations. In vertebrates in particular, TEs have been recognized as playing an important role in major evolutionary transitions and biodiversity. Moreover, in the last decade, a significant number of papers has been published highlighting a correlation between TE activity and exposition to environmental stresses and dietary factors. In this review we present an overview of the impact of TEs in vertebrate genomes, report the silencing mechanisms adopted by host genomes to regulate TE activity, and finally we explore the effects of environmental and dietary factor exposures on TE activity in mammals, which is the most studied group among vertebrates. The studies here reported evidence that several factors can induce changes in the epigenetic status of TEs and silencing mechanisms leading to their activation with consequent effects on the host genome. The study of TE can represent a future challenge for research for developing effective markers able to detect precocious epigenetic changes and prevent human diseases.
Assuntos
Elementos de DNA Transponíveis/genética , Estresse Fisiológico/genética , Vertebrados/genética , Animais , Epigênese Genética , Genoma , Humanos , Fenômenos Fisiológicos da NutriçãoRESUMO
Transposable elements (TEs) represent a considerable fraction of eukaryotic genomes, thereby contributing to genome size, chromosomal rearrangements, and to the generation of new coding genes or regulatory elements. An increasing number of works have reported a link between the genomic abundance of TEs and the adaptation to specific environmental conditions. Diadromy represents a fascinating feature of fish, protagonists of migratory routes between marine and freshwater for reproduction. In this work, we investigated the genomes of 24 fish species, including 15 teleosts with a migratory behaviour. The expected higher relative abundance of DNA transposons in ray-finned fish compared with the other fish groups was not confirmed by the analysis of the dataset considered. The relative contribution of different TE types in migratory ray-finned species did not show clear differences between oceanodromous and potamodromous fish. On the contrary, a remarkable relationship between migratory behaviour and the quantitative difference reported for short interspersed nuclear (retro)elements (SINEs) emerged from the comparison between anadromous and catadromous species, independently from their phylogenetic position. This aspect is likely due to the substantial environmental changes faced by diadromous species during their migratory routes.
Assuntos
Migração Animal , Elementos de DNA Transponíveis , Evolução Molecular , Peixes/genética , Animais , Peixes/fisiologia , Tamanho do Genoma , Filogenia , Elementos Nucleotídeos Curtos e DispersosRESUMO
The origin of the p53 gene family predates multicellular life since TP53 members of this gene family have been found in unicellular eukaryotes. In invertebrates one or two genes attributable to a TP53-like or TP63/73-like gene are present. The radiation into three genes, TP53, TP63, and TP73, has been reported as a vertebrate invention. TP53 is considered the "guardian of the genome" given its role in protecting cells against the DNA damage and cellular stressors. TP63 and TP73 play a role in epithelial development and neurogenesis, respectively. The evolution of the p53 gene family has been the subject of considerable analyses even if several questions remain still open. In this study we addressed the evolutionary history of the p53 gene family in vertebrates performing an extended microsyntenic investigation coupled with a phylogenetic analysis, together with protein domain organization and structure assessment. On the basis of our results we discussed a possible evolutionary scenario according to which a TP53/63/73 ancestor form gave rise to the current TP53 and a TP63/73 form, which in turn independently duplicated into two genes in agnathe and gnathostome lineages.
Assuntos
Evolução Molecular , Genes p53 , Vertebrados/genética , Animais , Filogenia , Domínios Proteicos , Vertebrados/classificaçãoRESUMO
The movement and accumulation of transposable elements (TEs) exert a great influence on the host genome, e.g. determining architecture and genome size, providing a substrate for homologous recombination and DNA rearrangements. TEs are also known to be responsive and susceptible to environmental changes. However, the correlation between environmental conditions and the sequence evolution of TEs is still an unexplored field of research. Among vertebrates, teleosts represent a successful group of animals adapted to a wide range of different environments and their genome is constituted by a rich repertoire of TEs. The Rex3 retroelement is a lineage-specific non-LTR retrotransposon and thus represents a valid candidate for performing comparative sequence analyses between species adapted to diverse temperature conditions. Partial reverse transcriptase sequences of the Rex3 retroelement belonging to 39 species of teleosts were investigated through phylogenetic analysis to evaluate whether the species' adaptation to different environments led to the evolution of different Rex3 temperature-related variants. Our findings highlight an intriguing behaviour of the analysed sequences, showing clustering of Rex3 sequences isolated from species living in cold waters (Arctic and Antarctic regions and cold waters of temperate regions) compared with those isolated from species living in warm waters. This is the first evidence to our knowledge of a correlation between environmental temperature and Rex3 retroelement evolution.
Assuntos
Genoma , Retroelementos , Animais , Regiões Antárticas , Elementos de DNA Transponíveis , Evolução Molecular , Filogenia , TemperaturaRESUMO
The discovery of a living coelacanth specimen in 1938 was remarkable, as this lineage of lobe-finned fish was thought to have become extinct 70 million years ago. The modern coelacanth looks remarkably similar to many of its ancient relatives, and its evolutionary proximity to our own fish ancestors provides a glimpse of the fish that first walked on land. Here we report the genome sequence of the African coelacanth, Latimeria chalumnae. Through a phylogenomic analysis, we conclude that the lungfish, and not the coelacanth, is the closest living relative of tetrapods. Coelacanth protein-coding genes are significantly more slowly evolving than those of tetrapods, unlike other genomic features. Analyses of changes in genes and regulatory elements during the vertebrate adaptation to land highlight genes involved in immunity, nitrogen excretion and the development of fins, tail, ear, eye, brain and olfaction. Functional assays of enhancers involved in the fin-to-limb transition and in the emergence of extra-embryonic tissues show the importance of the coelacanth genome as a blueprint for understanding tetrapod evolution.
Assuntos
Evolução Biológica , Peixes/classificação , Peixes/genética , Genoma/genética , Animais , Animais Geneticamente Modificados , Embrião de Galinha , Sequência Conservada/genética , Elementos Facilitadores Genéticos/genética , Evolução Molecular , Extremidades/anatomia & histologia , Extremidades/crescimento & desenvolvimento , Peixes/anatomia & histologia , Peixes/fisiologia , Genes Homeobox/genética , Genômica , Imunoglobulina M/genética , Camundongos , Anotação de Sequência Molecular , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Vertebrados/anatomia & histologia , Vertebrados/genética , Vertebrados/fisiologiaRESUMO
Repetitive DNA is an intriguing portion of the genome still not completely discovered and shows a high variability in terms of sequence, genomic organization, and evolutionary mode. On the basis of the genomic organization, it includes satellite DNAs, which are organized as long arrays of head-to-tail linked repeats, and transposable elements, which are dispersed throughout the genome. These repeated elements represent a considerable fraction of vertebrate genomes contributing significantly in species evolution. In this review, we focus our attention on Rex1, Rex3 and Rex6, three elements specific of teleost genomes. We report an overview of data available on these retroelements highlighting their significative impact in chromatin and heterochromatin organization, in the differentiation of sex chromosomes, in the formation of supernumerary chromosomes, and in karyotype evolution in teleosts.
Assuntos
Peixes/genética , Genoma , Retroelementos/genética , Animais , Evolução Molecular , Filogenia , Sequências Repetitivas de Ácido Nucleico/genéticaRESUMO
Repetitive DNA--sequence motifs repeated hundreds or thousands of times in the genome--makes up the major proportion of all the nuclear DNA in most eukaryotic genomes. However, the significance of repetitive DNA in the genome is not completely understood, and it has been considered to have both structural and functional roles, or perhaps even no essential role. High-throughput DNA sequencing reveals huge numbers of repetitive sequences. Most bioinformatic studies focus on low-copy DNA including genes, and hence, the analyses collapse repeats in assemblies presenting only one or a few copies, often masking out and ignoring them in both DNA and RNA read data. Chromosomal studies are proving vital to examine the distribution and evolution of sequences because of the challenges of analysis of sequence data. Many questions are open about the origin, evolutionary mode and functions that repetitive sequences might have in the genome. Some, the satellite DNAs, are present in long arrays of similar motifs at a small number of sites, while others, particularly the transposable elements (DNA transposons and retrotranposons), are dispersed over regions of the genome; in both cases, sequence motifs may be located at relatively specific chromosome domains such as centromeres or subtelomeric regions. Here, we overview a range of works involving detailed characterization of the nature of all types of repetitive sequences, in particular their organization, abundance, chromosome localization, variation in sequence within and between chromosomes, and, importantly, the investigation of their transcription or expression activity. Comparison of the nature and locations of sequences between more, and less, related species is providing extensive information about their evolution and amplification. Some repetitive sequences are extremely well conserved between species, while others are among the most variable, defining differences between even closely relative species. These data suggest contrasting modes of evolution of repetitive DNA of different types, including selfish sequences that propagate themselves and may even be transferred horizontally between species rather than by descent, through to sequences that have a tendency to amplification because of their sequence motifs, to those that have structural significance because of their bulk rather than precise sequence. Functional consequences of repeats include generation of variability by movement and insertion in the genome (giving useful genetic markers), the definition of centromeres, expression under stress conditions and regulation of gene expression via RNA moieties. Molecular cytogenetics and bioinformatic studies in a comparative context are now enabling understanding of the nature and behaviour of this major genomic component.
Assuntos
DNA , Eucariotos/genética , Genoma , Sequências Repetitivas de Ácido Nucleico , Genômica/métodosRESUMO
A considerable fraction of the eukaryotic genome is made up of satellite DNA constituted of tandemly repeated sequences. These elements are mainly located at centromeres, pericentromeres, and telomeres and are major components of constitutive heterochromatin. Although originally satellite DNA was thought silent and inert, an increasing number of studies are providing evidence on its transcriptional activity supporting, on the contrary, an unexpected dynamicity. This review summarizes the multiple structural roles of satellite noncoding RNAs at chromosome level. Indeed, satellite noncoding RNAs play a role in the establishment of a heterochromatic state at centromere and telomere. These highly condensed structures are indispensable to preserve chromosome integrity and genome stability, preventing recombination events, and ensuring the correct chromosome pairing and segregation. Moreover, these RNA molecules seem to be involved also in maintaining centromere identity and in elongation, capping, and replication of telomere. Finally, the abnormal variation of centromeric and pericentromeric DNA transcription across major eukaryotic lineages in stress condition and disease has evidenced the critical role that these transcripts may play and the potentially dire consequences for the organism.
Assuntos
DNA , Sequências de Repetição em Tandem , Transcrição Gênica , Animais , Centrômero/genética , DNA Satélite , Eucariotos/genética , Predisposição Genética para Doença , Heterocromatina/genética , Humanos , Camundongos , RNA não Traduzido/genética , Estresse Fisiológico/genética , Telômero/genética , Homeostase do Telômero/genéticaRESUMO
The aim of this work is to investigate the sequence conservation and the evolution of repeated DNA in related species. Satellite DNA is a component of eukaryotic genomes and is made up of tandemly repeated sequences. These sequences are affected by high rates of mutation that lead to the occurrence of species-specific satellite DNAs, which are different in terms of both quantity and quality. In this work, a novel repetitive DNA family, named PjHhaI sat, is described in Pecten jacobaeus. The quantitative analyses revealed a different abundance of this element in the molluscan species investigated in agreement with the "library hypothesis" even if, in this case, at a high taxonomic level. In addition, the qualitative analysis demonstrated an astonishing sequence conservation not only among scallops but also in six other molluscan species belonging to three classes. These findings suggest that the PjHhaI sat may be considered as the most ancients of DNA described so far, which remained "frozen" during molluscan evolution. The widespread distribution of this sat DNA in molluscs as well as its long evolutionary preservation open up questions on the functional role of this element. A future challenge might be the identification of proteins or molecules which interact with the PjHhaI sat.
Assuntos
DNA Satélite/genética , Pecten/genética , Animais , Sequência de Bases , Southern Blotting , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Análise de Sequência de DNA , Homologia de Sequência do Ácido NucleicoRESUMO
Hox and ParaHox genes are involved in patterning the anterior-posterior body axis in metazoans during embryo development. Body plan evolution and diversification are affected by variations in the number and sequence of Hox and ParaHox genes, as well as by their expression patterns. For this reason Hox and ParaHox gene investigation in the phylum Mollusca is of great interest, as this is one of the most important taxa of protostomes, characterized by a high morphological diversity. The comparison of the works reviewed here indicates that species of molluscs, belonging to different classes, share a similar composition of Hox and ParaHox genes. Therefore evidence suggests that the wide morphological diversity of this taxon could be ascribed to differences in Hox gene interactions and expressions and changes in the Hox downstream genes rather than to Hox cluster composition. Moreover the data available on Hox and ParaHox genes in molluscs compared with those of other Lophotrochozoa shed light on the complex and controversial evolutionary histories that these genes have undergone within protostomes.
Assuntos
Proteínas de Homeodomínio/genética , Moluscos/classificação , Moluscos/genética , Animais , Evolução Molecular , Família Multigênica , FilogeniaRESUMO
The morphological stasis of coelacanths has long suggested a slow evolutionary rate. General genomic stasis might also imply a decrease of transposable elements activity. To evaluate the potential activity of transposable elements (TEs) in "living fossil" species, transcriptomic data of Latimeria chalumnae and its Indonesian congener Latimeria menadoensis were compared through the RNA-sequencing mapping procedures in three different organs (liver, testis, and muscle). The analysis of coelacanth transcriptomes highlights a significant percentage of transcribed TEs in both species. Major contributors are LINE retrotransposons, especially from the CR1 family. Furthermore, some particular elements such as a LF-SINE and a LINE2 sequences seem to be more expressed than other elements. The amount of TEs expressed in testis suggests possible transposition burst in incoming generations. Moreover, significant amount of TEs in liver and muscle transcriptomes were also observed. Analyses of elements displaying marked organ-specific expression gave us the opportunity to highlight exaptation cases, that is, the recruitment of TEs as new cellular genes, but also to identify a new Latimeria-specific family of Short Interspersed Nuclear Elements called CoeG-SINEs. Overall, transcriptome results do not seem to be in line with a slow-evolving genome with poor TE activity.
Assuntos
Elementos de DNA Transponíveis/genética , Peixes/genética , Análise de Sequência de RNA , Transcriptoma , Animais , Sequência de Bases , Evolução Biológica , Evolução Molecular , Genoma , Fígado , Masculino , Músculos , Filogenia , Retroelementos/genética , Elementos Nucleotídeos Curtos e Dispersos , Especificidade da Espécie , TestículoRESUMO
Coelacanths are a critically valuable species to explore the gene changes that took place in the transition from aquatic to terrestrial life. One interesting and biologically relevant feature of the genus Latimeria is ureotelism. However not all urea is excreted from the body; in fact high concentrations are retained in plasma and seem to be involved in osmoregulation. The purine catabolic pathway, which leads to urea production in Latimeria, has progressively lost some steps, reflecting an enzyme loss during diversification of terrestrial species. We report the results of analyses of the liver and testis transcriptomes of the Indonesian coelacanth Latimeria menadoensis and of the genome of Latimeria chalumnae, which has recently been fully sequenced in the framework of the coelacanth genome project. We describe five genes, uricase, 5-hydroxyisourate hydrolase, parahox neighbor B, allantoinase, and allantoicase, each coding for one of the five enzymes involved in urate degradation to urea, and report the identification of a putative second form of 5-hydroxyisourate hydrolase that is characteristic of the genus Latimeria. The present data also highlight the activity of the complete purine pathway in the coelacanth liver and suggest its involvement in the maintenance of high plasma urea concentrations.
Assuntos
Peixes/genética , Peixes/metabolismo , Purinas/metabolismo , Transcriptoma , Amidoidrolases/genética , Animais , Evolução Molecular , Genes , Hidrolases/genética , Fígado/metabolismo , Masculino , Testículo/metabolismo , Urato Oxidase/genética , Ureo-Hidrolases/metabolismoRESUMO
Onopordum tauricum Willd., a species distributed in Eastern Europe, has been the subject of various research endeavors aimed at assessing its suitability for extracting vegetable rennet for use in the production of local cheeses as a substitute for animal-derived rennet. In Italy, the species has an extremely fragmented and localized distribution in six locations scattered across the central-northern Apennines and some areas of southern Italy. In this study, both the morphology and genetic diversity of the six known Italian populations were investigated to detect putative ecotypes. To this end, 33 morphological traits were considered for morphometric measurements, while genetic analysis was conducted on the entire genome using the ddRAD-Seq method. Both analyses revealed significant differences among the Apennine populations (SOL, COL, and VIS) and those from southern Italy (ROT, PES, and LEC). Specifically, the southern Italian populations appear to deviate significantly in some characteristics from the typical form of the species. Therefore, its attribution to O. tauricum is currently uncertain, and further genetic and morphological analyses are underway to ascertain its systematic placement within the genus Onopordum.
RESUMO
BACKGROUND: Latimeria menadoensis is a coelacanth species first identified in 1997 in Indonesia, at 10,000 Km of distance from its African congener. To date, only six specimens have been caught and just a very limited molecular data is available. In the present work we describe the de novo transcriptome assembly obtained from liver and testis samples collected from the fifth specimen ever caught of this species. RESULTS: The deep RNA sequencing performed with Illumina technologies generated 145,435,156 paired-end reads, accounting for ~14 GB of sequence data, which were de novo assembled using a Trinity/CLC combined strategy. The assembly output was processed and filtered producing a set of 66,308 contigs, whose quality was thoroughly assessed. The comparison with the recently sequenced genome of the African congener Latimeria chalumnae and with the available genomic resources of other vertebrates revealed a good reconstruction of full length transcripts and a high coverage of the predicted full coelacanth transcriptome. CONCLUSION: Given the high genomic affinity between the two coelacanth species, the here described de novo transcriptome assembly can be considered a valuable support tool for the improvement of gene prediction within the genome of L. chalumnae and a valuable resource for investigation of many aspects of tetrapod evolution.
Assuntos
Peixes/genética , Transcriptoma , Animais , Evolução Biológica , Mapeamento de Sequências Contíguas , Sequenciamento de Nucleotídeos em Larga Escala , Indonésia , Fígado/metabolismo , Masculino , Análise de Sequência de RNA , Testículo/metabolismoRESUMO
The coelacanth Latimeria menadoensis, a living fossil, occupies a key phylogenetic position to explore the changes that have affected the genomes of the aquatic vertebrates that colonized dry land. This is the first study to isolate and analyze L. menadoensis mRNA. Three different vitellogenin transcripts were identified and their inferred amino acid sequences compared to those of other known vertebrates. The phylogenetic data suggest that the evolutionary history of this gene family in coelacanths was characterized by a different duplication event than those which occurred in teleosts, amniotes, and amphibia. Comparison of the three sequences highlighted differences in functional sites. Moreover, despite the presence of conserved sites compared with the other oviparous vertebrates, some sites were seen to have changed, others to be similar only to those of teleosts, and others still to resemble only to those of tetrapods.
Assuntos
Peixes/genética , Filogenia , RNA/genética , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Teorema de Bayes , Biologia Computacional , Primers do DNA/genética , DNA Complementar/genética , Peixes/classificação , Genes Duplicados/genética , Indonésia , Fígado/metabolismo , Masculino , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie , Testículo/metabolismoRESUMO
Ray-finned fish represent a very interesting group of vertebrates comprising a variety of organisms living in different aquatic environments worldwide. In the case of stenothermal fish, thermal fluctuations are poorly tolerated, thus ambient temperature represents a critical factor. In this paper, we considered the tiger barb Puntius tetrazona, a freshwater fish belonging to the family Cyprinidae, living at 21-28 °C. We analyzed the available RNA-Seq data obtained from specimens exposed at 27 °C and 13 °C to investigate the transcriptional activity of transposable elements (TEs) and genes encoding for proteins involved in their silencing in the brain, gill, and liver. TEs are one of the tools generating genetic variability that underlies biological evolution, useful for organisms to adapt to environmental changes. Our findings highlighted a different response of TEs in the three analyzed tissues. While in the brain and gill, no variation in TE transcriptional activity was observed, a remarkable increase at 13 °C was recorded in the liver. Moreover, the transcriptional analysis of genes encoding proteins involved in TE silencing such as heterochromatin formation, the NuRD complex, and the RISC complex (e.g., AGO and GW182 proteins) highlighted their activity in the hepatic tissue. Overall, our findings suggested that this tissue is a target organ for this kind of stress, since TE activation might regulate the expression of stress-induced genes, leading to a better response of the organism to temperature changes. Therefore, this view corroborates once again the idea of a potential role of TEs in organism rapid adaptation, hence representing a promising molecular tool for species resilience.
RESUMO
Autism is a severe neurodevelopmental disorder leading to deficits in social interaction, communication, and several activities. An increasing number of evidence suggests a role of oxidative stress in the etiology of autism spectrum disorder (ASD). Indeed, impaired antioxidant mechanisms may lead to the inadequate removal of H2 O2 with a consequent increase in highly active hydroxyl radicals and other reactive oxygen species causing cellular damages. The GPx1 is one of the most important enzymes counteracting oxidative stress. In this work, we investigated a possible correlation between the GCG repeat polymorphism present in the first exon of GPx1 gene encoding a tract of five to seven alanine residues (ALA5, ALA6, and ALA7) and ASD. Our findings highlighted a high frequency of ALA5 allele in ASD subjects. Moreover, proteins corresponding to the three GPx1 variants were produced in vitro, and the evaluation of their activity showed a lower values for GPx1 having ALA5 polymorphism. The comparison of the secondary and tertiary structure predictions revealed an alpha-helix in correspondence of alanine stretch only in the case of GPx1-ALA7 variant. Finally, to better investigate protein structure, steady-state fluorescence measurements of GPx1 intrinsic tryptophan were carried out and the three tested proteins exhibited a different stability under denaturing conditions. This work demonstrates the importance in adopting a multidisciplinary strategy to comprehend the role of GPx1 in ASD. LAY SUMMARY: Results here obtained suggest a possible role of ALA5 GPx1 variant in ASD. However, given the multifactorial nature of autism, this evidence might be a piece of a more complex puzzle being the GPx1 enzyme part of a complex pathway in which several proteins are involved.