RESUMO
Mitochondria play a key role in cell biology and have their own genome, residing in a highly oxidative environment that induces faster changes than the nuclear genome. Because of this, mitochondrial markers have been exploited to reconstruct phylogenetic and phylogeographic relationships in studies of adaptation and molecular evolution. In this study, we determined the complete mitogenome of the fungus-farming ant Mycetophylax simplex (Hymenoptera, Formicidae) and conducted a comparative analysis among 29 myrmicine ant mitogenomes. Mycetophylax simplex is an endemic ant that inhabits sand dunes along the southern Atlantic coast. Specifically, the species occur in the ecosystem known as "restinga", within the Atlantic Forest biome. Due to habitat degradation, land use and decline of restinga habitats, the species is considered locally extinct in extremely urban beaches and is listed as vulnerable on the Brazilian Red List (ICMBio). We employed a mitochondrion-targeting approach to obtain the complete mitogenome through high-throughput DNA sequencing technology. This method allowed us to determine the mitogenome with high performance, coverage and low cost. The circular mitogenome has a length of 16,367 base pairs enclosing 37 genes (13 protein-coding genes, 22 tRNAs and 2 rRNAs) along with one control region (CR). All the protein-coding genes begin with a typical ATN codon and end with the canonical stop codons. All tRNAs formed the fully paired acceptor stems and fold into the typical cloverleaf-shaped secondary structures. The gene order is consistent with the shared Myrmicinae structure, and the A + T content of the majority strand is 81.51%. Long intergenic spacers were not found but some gene are slightly shorter. The phylogenetic relationships based on concatenated nucleotide and amino acid sequences of the 13 protein-coding genes, using Maximum Likelihood and Bayesian Inference methods, indicated that mitogenome sequences were useful in resolving higher-level relationship within Formicidae.
Assuntos
Formigas , Genoma Mitocondrial , Animais , Genoma Mitocondrial/genética , Ecossistema , Teorema de Bayes , Filogenia , Mitocôndrias/genética , Formigas/genéticaRESUMO
Abstract Aging has a direct impact on balance due to changes in sensory and motor response, sarcopenia, reduced muscle strength and range of motion that occur in the elderly. In this context, strength training (ST) programs are seen as a valuable strategy to minimize the deleterious effect of aging on strength production and balance in this population. The purpose of the study was to evaluate the effect of 12 weeks of progressive intensity ST on static balance variables in the elderly. The study included 23 elderly with an average age of 65±8.61 years, of both sexes, who performed a twelve-week strength training program, with a frequency of three times a week and with progressive intensity (60 - 85% of 1-RM). Balance was assessed before and after the intervention period, through stabilometric assessment on a force plate. After the intervention, there was a reduction in the anteroposterior amplitude (p=0.01), in the anteroposterior velocity (p=0.01) and in the total displaced area (p=0.04). It is concluded that the strength training can be used as a key tool to minimize the deleterious effect of aging on the maintenance of static balance.
Resumo O envelhecimento tem impacto direto no equilíbrio devido a alterações da resposta sensorial e motora, sarcopenia e redução da força muscular e da amplitude de movimento que ocorre nos idosos. Nesse contexto, programas de treinamento de força (TF) são vistos como valiosa estratégia para minimizar o efeito deletério do envelhecimento na produção de força e no equilíbrio dessa população. O objetivo do estudo foi avaliar o efeito de 12 semanas de TF com intensidade progressiva sobre as variáveis de equilíbrio estático em idosos. Participaram do estudo 23 idosos com idade média de 65±8,61 anos, de ambos os sexos, que realizaram um programa de TF de doze semanas, com frequência de três vezes por semana e com intensidade progressiva (60 - 85% de 1-RM). O equilíbrio foi avaliado antes e após o período de intervenção, por meio de avaliação estabilométrica em plataforma de força. Após a intervenção houve redução na amplitude anteroposterior (p=0,01), na velocidade anteroposterior (p=0,01) e na área total deslocada (p= 0,04). Conclui-se que o treinamento de força pode ser utilizado como ferramenta chave para minimizar o efeito deletério do envelhecimento na manutenção do equilíbrio estático.
RESUMO
OBJECTIVE: The objective of this study was to evaluate the effects of 12 weeks of resistance training (RT) with progressive intensity on factors associated with sarcopenia in older individuals. METHODS: A cross-sectional study was conducted with 74 participants (64.27 ± 7.06-y-old) who were divided into a control group (n = 37) and an intervention group (n = 37). The intervention group underwent 12 weeks of RT three times a week, with an initial training of 60% and final training of 85% of one-repetition maximum (1RM). Both groups were evaluated before and after the 12-week training period to assess improvements in strength and physical performance. RESULTS: The intervention group showed an increase in physical performance, as evidenced by a reduction in the time to perform the Timed Up and Go (TUG) test (p < 0.01) and the Five Times Sit to Stand Test (p < 0.01). Furthermore, the RT proved to be efficient for increasing hand grip and overall muscular strength, as confirmed through the 1RM test. However, the muscle mass index (MMI) and walking speed did not show any significant alterations in both groups. CONCLUSIONS: In conclusion, 12 weeks of RT with progressive intensity has a positive effect on the diagnostic parameters of sarcopenia, leading to improvements in physical performance and muscular strength while maintaining the MMI.
Assuntos
Treinamento Resistido , Sarcopenia , Humanos , Idoso , Sarcopenia/diagnóstico , Força da Mão/fisiologia , Estudos Transversais , Força Muscular/fisiologiaRESUMO
The global population of Dicotyles tajacu (Linnaeus, 1758) (Cetartiodactyla: Tayassuidae), commonly known as the collared peccary and distributed in the Neotropics, is currently in decline due to anthropogenic pressures. In this study, five microsatellite loci were used to genetically characterize a group of 20 captive-born collared peccaries intended for reintroduction. This study aimed to evaluate the genetic diversity and relatedness of captive individuals using microsatellite markers. The genetic data generated were used to evaluate the viability of the reintroduction and to propose measures for the management and conservation of this species. In this study, we found relatively high genetic diversity indices, indicating that the group was genetically diverse. Inbreeding coefficients with negative values were observed, indicating an excess of alleles in heterozygosis and an absence of inbreeding. One locus showed deviation from Hardy-Weinberg equilibrium, which may have been caused by the mixing of individuals from different origins. Relatedness analysis indicated that some individuals were highly related, with coefficients indicating they may be first-degree relatives. Our findings indicate that the studied group has enough genetic diversity to be released into nature, but the high individual relatedness found would require the adoption of strategies after the release of animals in the wild to ensure their persistence.
Assuntos
Animais de Zoológico , Artiodáctilos , Animais , Genótipo , Animais de Zoológico/genética , Artiodáctilos/genética , Repetições de Microssatélites/genética , Sequenciamento de Nucleotídeos em Larga Escala , Variação GenéticaRESUMO
Individual variation in milk fatty acid (FA) composition has been partially attributed to stearoyl-CoA desaturase 1 (SCD1) gene polymorphisms in taurine breeds, but much less is known for Zebu breeds. This study investigated the phenotypic variation in milk FA composition, and the influence of SCD1 variants on this trait and on milk fat desaturase indices (DI) in Gir cows. The functional impact of SCD1 variants was predicted using bioinformatics tools. Milk and blood samples were collected from 312 cows distributed in 10 herds from five states of Brazil. SCD1 variants were identified through target sequencing, and milk FA composition was determined by gas chromatography. Phenotypic variation in milk FA composition fell within the range reported for taurine breeds, with SCD18 index showing the lowest variation among the DI. Fourteen SCD1 variants were identified, six of which not previously described. Regarding the A293V polymorphism, all cows were homozygous for the C allele (coding for alanine), whereas all genotypes were detected for the second SNP affecting the 293 codon (G > A), with compelling evidence for functional effects. Significant associations (based on raw p-values) were found between this SNP and C12:0, cis-9, trans-11 CLA and short-chain FA, and between another SNP (rs523411937) and C15:0 and odd-chain linear FA. A new SNP on Chr26:21277069 was associated with trans-11 C18:1, cis-9, trans-11 CLA, C18:3 n-3 and n-3 FA. These findings indicate that SCD1 polymorphisms also contributes to the phenotypic variation in milk FA composition of Gir cows, with potential use in their breeding programmes.
Assuntos
Ácidos Graxos , Leite , Feminino , Bovinos/genética , Animais , Estearoil-CoA Dessaturase/genética , Polimorfismo Genético , Variação Biológica da PopulaçãoRESUMO
The objective of this study was to verify the influence of the ACTN3 R577X polymorphism on muscle damage and the inflammatory response after an acute strength training (ST) session. Twenty-seven healthy male individuals (age: 25 ± 4.3 years) participated in the study, including 18 RR/RX and 9 XX individuals. The participants were divided into two groups (RR/RX and XX groups) and subjected to an acute ST session, which consisted of a series of leg press, leg extension machine, and seated leg curl machine. The volunteers were instructed to perform the greatest volume of work until concentric muscle failure. Each volunteer's performance was analyzed as the load and total volume of training, and the blood concentrations of C-C motif chemokine ligand 2 (CCL2), interleukin-8 (IL-8), creatine kinase (CK), lactate dehydrogenase (LDH), myoglobin, testosterone, and cortisol were measured before the ST session and 30 min and 24 h postsession. The ACTN3 R577X polymorphism effect was observed, with increased concentrations of CCL2 (p < 0.01), IL-8 (p < 0.01), and LDH (p < 0.001) in XX individuals. There was an increase in the concentration of CK in the RR/RX group compared to XX at 24 h after training (p > 0.01). The testosterone/cortisol ratio increased more markedly in the XX group (p < 0.001). Regarding performance, the RR/RX group presented higher load and total volume values in the training exercises when compared to the XX group (p < 0.05). However, the XX group presented higher values of delayed onset muscle soreness (DOMS) than the RR/RX group (p < 0.05). The influence of ACTN3 R577X polymorphism on muscle damage and the inflammatory response was observed after an acute ST session, indicating that the RR/RX genotype shows more muscle damage and a catabolic profile due to a better performance in this activity, while the XX genotype shows more DOMS.
Assuntos
Actinina , Força Muscular , Mialgia , Treinamento Resistido , Adulto , Humanos , Masculino , Adulto Jovem , Actinina/genética , Genótipo , Hidrocortisona , Interleucina-8/genética , Força Muscular/genética , Músculos/metabolismo , Mialgia/etiologia , Mialgia/genética , Mialgia/metabolismo , Treinamento Resistido/efeitos adversos , Treinamento Resistido/métodos , TestosteronaRESUMO
Whole genome sequencing of bovine breeds has allowed identification of genetic variants in milk protein genes. However, functional repercussion of such variants at a molecular level has seldom been investigated. Here, the results of a multistep Bioinformatic analysis for functional characterization of recently identified genetic variants in Brazilian Gyr and Guzerat breeds is described, including predicted effects on the following: (i) evolutionary conserved nucleotide positions/regions; (ii) protein function, stability, and interactions; (iii) splicing, branching, and miRNA binding sites; (iv) promoters and transcription factor binding sites; and (v) collocation with QTL. Seventy-one genetic variants were identified in the caseins (CSN1S1, CSN2, CSN1S2, and CSN3), LALBA, LGB, and LTF genes. Eleven potentially regulatory variants and two missense mutations were identified. LALBA Ile60Val was predicted to affect protein stability and flexibility, by reducing the number the disulfide bonds established. LTF Thr546Asn is predicted to generate steric clashes, which could mildly affect iron coordination. In addition, LALBA Ile60Val and LTF Thr546Asn affect exonic splicing enhancers and silencers. Consequently, both mutations have the potential of affecting immune response at individual level, not only in the mammary gland. Although laborious, this multistep procedure for classifying variants allowed the identification of potentially functional variants for milk protein genes.
Assuntos
Caseínas , Proteínas do Leite , Animais , Bovinos/genética , Simulação por Computador , Mutação , Regiões Promotoras GenéticasRESUMO
Wistar Audiogenic Rat is an epilepsy model whose animals are predisposed to develop seizures induced by acoustic stimulation. This model was developed by selective reproduction and presents a consistent genetic profile due to the several generations of inbreeding. In this study, we performed an analysis of WAR RNA-Seq data, aiming identified at genetic variants that may be involved in the epileptic phenotype. Seventeen thousand eighty-five predicted variants were identified as unique to the WAR model, of which 15,915 variants are SNPs and 1,170 INDELs. We filter the predicted variants by pre-established criteria and selected five for validation by Sanger sequencing. The genetic variant c.14198T>C in the Vlgr1 gene was confirmed in the WAR model. Vlgr1 encodes an adhesion receptor that is involved in the myelination process, in the development of stereocilia of the inner ear, and was already associated with the audiogenic seizures presented by the mice Frings. The transcriptional quantification of Vlgr1 revealed the downregulation this gene in the corpus quadrigeminum of WAR, and the protein modeling predicted that the mutated residue alters the structure of a domain of the VLGR1 receptor. We believe that Vlgr1 gene may be related to the predisposition of WAR to seizures and suggest the mutation Vlgr1/Q4695R as putative causal variant, and the first molecular marker of the WAR strain.
RESUMO
The aim was to investigate a possible role of the ACTN3 R577X polymorphism in a Brazilian football player's career progression. 2 questions were formulated: 1. Does ACTN3 polymorphism affect the probability of an individual being a professional football player? 2. Does this polymorphism affect the progression of the athlete throughout his career? The study included 353 players from first division Brazilian football clubs in the following categories: under-14 (U-14), U-15, U-17, U-20, and professional (PRO). The control group (CON) was composed of 100 healthy non-athletes. The chi-squared test was used to assess differences between the allele and genotype frequencies. Comparing football categories, the XX genotype was less frequent among professional players than in the U-20 (p<0.05) or the U-15 category (p<0.05). The RX genotype also presented more frequently in the PRO category than the U-14 category (p<0.05). Moreover, a trend towards a higher frequency of the RX genotype and a lower frequency of the XX genotype was observed in the professional category compared to U-20. These results suggest that the genotype in the ACTN3 polymorphism affects the probability of a football player progressing throughout his career and becoming professional, meaning that playing football selects against the ACTN3 XX genotype.
Assuntos
Logro , Actinina/genética , Atletas , Polimorfismo Genético , Futebol , Adolescente , Adulto , Alelos , Brasil , Frequência do Gene , Genótipo , Humanos , Masculino , Adulto JovemRESUMO
This study aimed to analyze the angiotensin-converting enzyme (ACE-I/D) allelic and genotypic frequencies in Brazilian soccer players of different ages. The study group comprised 353 players from first-division clubs in the under (U)-14, U-15, U-17, U-20, and professional categories. The allelic and genotypic frequencies did not differ significantly in any of the categories between the group of players and the control group. This was the first study of ACE-I/D polymorphism in Brazilian soccer players.