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1.
Nature ; 592(7856): 756-762, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33408411

RESUMO

Egg-laying mammals (monotremes) are the only extant mammalian outgroup to therians (marsupial and eutherian animals) and provide key insights into mammalian evolution1,2. Here we generate and analyse reference genomes of the platypus (Ornithorhynchus anatinus) and echidna (Tachyglossus aculeatus), which represent the only two extant monotreme lineages. The nearly complete platypus genome assembly has anchored almost the entire genome onto chromosomes, markedly improving the genome continuity and gene annotation. Together with our echidna sequence, the genomes of the two species allow us to detect the ancestral and lineage-specific genomic changes that shape both monotreme and mammalian evolution. We provide evidence that the monotreme sex chromosome complex originated from an ancestral chromosome ring configuration. The formation of such a unique chromosome complex may have been facilitated by the unusually extensive interactions between the multi-X and multi-Y chromosomes that are shared by the autosomal homologues in humans. Further comparative genomic analyses unravel marked differences between monotremes and therians in haptoglobin genes, lactation genes and chemosensory receptor genes for smell and taste that underlie the ecological adaptation of monotremes.


Assuntos
Evolução Biológica , Genoma , Ornitorrinco/genética , Tachyglossidae/genética , Animais , Feminino , Masculino , Mamíferos/genética , Filogenia , Cromossomos Sexuais/genética
2.
Mol Biol Evol ; 39(6)2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35652727

RESUMO

Egg-laying mammals (monotremes) are a sister clade of therians (placental mammals and marsupials) and a key clade to understand mammalian evolution. They are classified into platypus and echidna, which exhibit distinct ecological features such as habitats and diet. Chemosensory genes, which encode sensory receptors for taste and smell, are believed to adapt to the individual habitats and diet of each mammal. In this study, we focused on the molecular evolution of bitter taste receptors (TAS2Rs) in monotremes. The sense of bitter taste is important to detect potentially harmful substances. We comprehensively surveyed agonists of all TAS2Rs in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus) and compared their functions with orthologous TAS2Rs of marsupial and placental mammals (i.e., therians). As results, the agonist screening revealed that the deorphanized monotreme receptors were functionally diversified. Platypus TAS2Rs had broader receptive ranges of agonists than those of echidna TAS2Rs. While platypus consumes a variety of aquatic invertebrates, echidna mainly consumes subterranean social insects (ants and termites) as well as other invertebrates. This result indicates that receptive ranges of TAS2Rs could be associated with feeding habits in monotremes. Furthermore, some orthologous receptors in monotremes and therians responded to ß-glucosides, which are feeding deterrents in plants and insects. These results suggest that the ability to detect ß-glucosides and other substances might be shared and ancestral among mammals.


Assuntos
Ornitorrinco , Tachyglossidae , Animais , Eutérios/genética , Feminino , Mamíferos/genética , Placenta , Ornitorrinco/genética , Gravidez , Paladar
3.
Am J Primatol ; 85(12): e23555, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37766673

RESUMO

Although knowledge of the functions of the gut microbiome has increased greatly over the past few decades, our understanding of the mechanisms governing its ecology and evolution remains obscure. While host genetic distance is a strong predictor of the gut microbiome in large-scale studies and captive settings, its influence has not always been evident at finer taxonomic scales, especially when considering among the recently diverged animals in natural settings. Comparing the gut microbiome of 19 populations of Japanese macaques Macaca fuscata across the Japanese archipelago, we assessed the relative roles of host genetic distance, geographic distance and dietary factors in influencing the macaque gut microbiome. Our results suggested that the macaques may maintain a core gut microbiome, while each population may have acquired some microbes from its specific habitat/diet. Diet-related factors such as season, forest, and reliance on anthropogenic foods played a stronger role in shaping the macaque gut microbiome. Among closely related mammalian hosts, host genetics may have limited effects on the gut microbiome since the hosts generally have smaller physiological differences. This study contributes to our understanding of the relative roles of host phylogeography and dietary factors in shaping the gut microbiome of closely related mammalian hosts.


Assuntos
Microbioma Gastrointestinal , Macaca fuscata , Animais , Macaca/genética , Mamíferos/genética , Dieta/veterinária , RNA Ribossômico 16S/genética
4.
Proc Biol Sci ; 288(1948): 20210346, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33849315

RESUMO

Bitter taste facilitates the detection of potentially harmful substances and is perceived via bitter taste receptors (TAS2Rs) expressed on the tongue and oral cavity in vertebrates. In primates, TAS2R16 specifically recognizes ß-glucosides, which are important in cyanogenic plants' use of cyanide as a feeding deterrent. In this study, we performed cell-based functional assays for investigating the sensitivity of TAS2R16 to ß-glucosides in three species of bamboo lemurs (Prolemur simus, Hapalemur aureus and H. griseus), which primarily consume high-cyanide bamboo. TAS2R16 receptors from bamboo lemurs had lower sensitivity to ß-glucosides, including cyanogenic glucosides, than that of the closely related ring-tailed lemur (Lemur catta). Ancestral reconstructions of TAS2R16 for the bamboo-lemur last common ancestor (LCA) and that of the Hapalemur LCA showed an intermediate sensitivity to ß-glucosides between that of the ring-tailed lemurs and bamboo lemurs. Mutagenetic analyses revealed that P. simus and H. griseus had separate species-specific substitutions that led to reduced sensitivity. These results indicate that low sensitivity to ß-glucosides at the cellular level-a potentially adaptive trait for feeding on cyanogenic bamboo-evolved independently after the Prolemur-Hapalemur split in each species.


Assuntos
Lemur , Lemuridae , Animais , Glucosídeos , Especificidade da Espécie , Paladar
5.
Yeast ; 38(10): 541-548, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34089530

RESUMO

In this study, we analysed the intracellular fatty acid profiles of Komagataella phaffii during methylotrophic growth. K. phaffii grown on methanol had significantly lower total fatty acid contents in the cells compared with glucose-grown cells. C18 and C16 fatty acids were the predominant fatty acids in K. phaffii, although the contents of odd-chain fatty acids such as C17 fatty acids were also relatively high. Moreover, the intracellular fatty acid composition of K. phaffii changed in response to not only carbon sources but also methanol concentrations: C17 fatty acids and C18:2 content increased significantly as methanol concentration increased, whereas C18:1 and C18:3 contents were significantly lower in methanol-grown cells. The intracellular content of unidentified compounds (Cn H2n O4 ), on the other hand, was significantly greater in cells grown on methanol. As the intracellular contents of these Cn H2n O4 compounds were significantly higher in a gene-disrupted strain for glutathione peroxidase (gpx1Δ) than in the wild-type strain, we presume that the Cn H2n O4 compounds are fatty acid peroxides. These results indicate that K. phaffii can coordinate intracellular fatty acid composition during methylotrophic growth in order to adapt to high-methanol conditions and that certain fatty acid species such as C17:0, C17:1, C17:2 and C18:2 may be related to the physiological functions by which K. phaffii adapts to high-methanol conditions.


Assuntos
Metanol , Saccharomycetales , Ácidos Graxos , Leveduras
6.
Artigo em Inglês | MEDLINE | ID: mdl-33906706

RESUMO

Three strains (YZ01T, YZ02 and YZ03) of Gram-stain-positive, facultatively anaerobic rods were isolated from the forestomach contents collected from a captive male proboscis monkey (Nasalis larvatus) at Yokohama Zoo in Japan. Phylogenetic analysis of the 16S rRNA gene sequences revealed that these strains belonged to the genus Lactobacillus. Based on the sequence similarity of the 16S rRNA gene, Lactobacillus delbrueckii subsp. indicus JCM 15610T was the closest phylogenetic neighbour to YZ01T. Sequence analyses of two partial concatenated housekeeping genes, the RNA polymerase alpha subunit (rpoA) and phenylalanyl-tRNA synthase alpha subunit (pheS) also indicated that the novel strains belonged to the genus Lactobacillus. The average nucleotide identity and digital DNA-DNA hybridization (dDDH) between L. delbrueckii subsp. indicus and YZ01T were 85.9 and 31.4 %, respectively. The phylogenetic tree based on the whole genomic data of strains YZ01T, YZ02 and YZ03 suggested that these three strains formed a single monophyletic cluster in the genus Lactobacillus, indicating that it belonged to a new species. The DNA G+C content of strain YZ01T was 51.6 mol%. The major fatty acids were C16 : 0 and C18 : 1 ω9c. Therefore, based on phylogenetic, phenotypic and physiological evidence, strains YZ01T, YZ02 and YZ03 represent a novel species of the genus Lactobacillus, for which the name Lactobacillus nasalidis sp. nov. is proposed with the type strain YZ01T (=JCM 33769T=DSM 110539T).


Assuntos
Lactobacillus/classificação , Filogenia , Presbytini/microbiologia , Estômago/microbiologia , Animais , Animais de Zoológico/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Ácidos Graxos/química , Genes Bacterianos , Japão , Lactobacillus/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Biol Pharm Bull ; 44(10): 1514-1523, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34602560

RESUMO

Drug-induced liver injury (DILI) is a common adverse drug event. Spontaneous reporting systems such as the Japanese Adverse Event Report Database (JADER) have been used to evaluate the association between drugs and adverse drug events. However, the association of drugs with adverse drug events may be overestimated due to reporting biases. Therefore, it is important to objectively evaluate the association using liver function test values. The aim of the present study was to predict potential hepatotoxic drugs using real-world data including electronic medical records and the JADER database. A total of 70009 (2779 with DILI and 67230 without DILI) and 438515 (10235 with DILI and 428280 without DILI) Japanese adult patients were extracted from electronic medical records and the JADER database, respectively. Drugs with ≥100 DILI patients in both of the two databases were regarded as suspected drugs for DILI. We used multivariate logistic regression to evaluate the association between the suspected drugs and increased risk of DILI. Among the suspected drugs, broad-spectrum antibiotics such as meropenem, tazobactam/piperacillin and ceftriaxone were significantly associated with an increased risk of DILI, and meropenem had a greater risk of DILI in both of the two databases. Additionally, there were significant associations of mosapride and L-carbocisteine with increased risk of DILI. In addition to well-known associations between antibiotic drugs and DILI, mosapride and L-carbocisteine were found to be new potential signals of drugs causing hepatotoxicity. This study indicates potential hepatotoxic drugs that require further causality assessment.


Assuntos
Sistemas de Notificação de Reações Adversas a Medicamentos/estatística & dados numéricos , Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Bases de Dados Factuais/estatística & dados numéricos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Causalidade , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Feminino , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Farmacovigilância , Fatores de Risco
8.
Am J Primatol ; 83(5): e23242, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33566369

RESUMO

Within the gastrointestinal tract, the physiochemical microenvironments are highly diversified among the different stages of food digestion. Accordingly, gut microbiome composition and function vary at different gut sites. In this study, we examine and compare the compositional and functional potential between the stomach and colonic microbiome of wild Japanese macaques (Macaca fuscata yakui) living in the evergreen forest of Yakushima Island. We find a significantly lower microbial diversity in the stomach than in the colon, possibly due to the stomach's acidic and aerobic environment, which is suboptimal for microbial survival. According to past studies, the microbial taxa enriched in the stomach are aero- and acid-tolerant. By functional prediction through PICRUSt2, we reveal that the stomach microbiome is more enriched in pathways relating to the metabolism of simple sugars. On the contrary, the colonic microbiota is more enriched with fiber-degrading microbes, such as those from Lachnospiracea, Ruminococcaceae, and Prevotella. Our study shows a clear difference in the microbiome between the stomach and colon of Japanese macaques in both composition and function. This study provides a preliminary look at the alpha diversity and taxonomic composition within the stomach microbiome of Japanese macaques, a hindgut-fermenting nonhuman primate.


Assuntos
Microbioma Gastrointestinal , Macaca fuscata , Animais , Colo , Macaca , Estômago
9.
Microb Ecol ; 80(2): 459-474, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32328670

RESUMO

Wild Japanese macaques (Macaca fuscata Blyth) living in the highland and lowland areas of Yakushima are known to have different diets, with highland individuals consuming more leaves. We aim to clarify whether and how these differences in diet are also reflected by gut microbial composition and fermentation ability. Therefore, we conduct an in vitro fermentation assay using fresh feces from macaques as inoculum and dry leaf powder of Eurya japonica Thunb. as a substrate. Fermentation activity was higher for feces collected in the highland, as evidenced by higher gas and butyric acid production and lower pH. Genetic analysis indicated separation of highland and lowland in terms of both community structure and function of the gut microbiota. Comparison of feces and suspension after fermentation indicated that the community structure changed during fermentation, and the change was larger for lowland samples. Analysis of the 16S rRNA V3-V4 barcoding region of the gut microbiota showed that community structure was clearly clustered between the two areas. Furthermore, metagenomic analysis indicated separation by gene and pathway abundance patterns. Two pathways (glycogen biosynthesis I and D-galacturonate degradation I) were enriched in lowland samples, possibly related to the fruit-eating lifestyle in the lowland. Overall, we demonstrated that the more leaf-eating highland Japanese macaques harbor gut microbiota with higher leaf fermentation ability compared with the more fruit-eating lowland ones. Broad, non-specific taxonomic and functional gut microbiome differences suggest that this pattern may be driven by a complex interplay between many taxa and pathways rather than single functional traits.


Assuntos
Bactérias/metabolismo , Digestão , Comportamento Alimentar , Microbioma Gastrointestinal/fisiologia , Macaca fuscata/microbiologia , Macaca fuscata/fisiologia , Animais , Bactérias/genética , Dieta , Fermentação , Metagenoma , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
10.
Biosci Biotechnol Biochem ; 84(2): 393-401, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31608802

RESUMO

In experiments 1 and 2, effect of ingestion of maltobionic acid calcium salt (MBCa) on recovery of rats from a latent iron deficiency and from iron deficiency anemia was examined, respectively. After grouping rats into control and iron-deficiency groups, a latent iron deficiency or iron-deficiency anemia was induced in the latter group. And recovery from these states by MBCa containing diets (0%, 3%, and 6% MBCa in diet, classified into MBCa-0, MBCa-3, and MBCa-6 groups) was compared for convalescence period in light of iron sufficient control group. In experiment 1, MBCa ingestion significantly increased the iron concentration in the serum and liver, and promoted recovery from a latent iron deficiency. In experiment 2, hemoglobin and hematocrit levels increased significantly with MBCa intake, and recovery from iron-deficiency anemia was promoted. MBCa effectively promoted the recovery of rats from a subclinical iron deficiency and iron-deficiency anemia.Abbreviations: ANOVA: analysis of variance; DMT1: divalent metal transporter 1; EDTA-2Na: disodium salt of ethylenediaminetetraacetic acid; Fpn: feroportin; Hb: hemoglobin; Ht: hematocrit; ICP-OES: inductivity coupled plasma optical emission spectrometer; MBCa: maltobionic acid calcium salt; nitroso-PSAP: 2-nitroso-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol; SE: standard error; SI: serum-iron concentration; TSAT: transferrin saturation; TIBC: total iron-binding capacity; UIBC: unsaturated iron-binding capacity.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Dissacarídeos/uso terapêutico , Animais , Dieta , Dissacarídeos/administração & dosagem , Masculino , Ratos , Ratos Wistar
11.
Genome Res ; 26(3): 301-14, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26728716

RESUMO

New genes contribute substantially to adaptive evolutionary innovation, but the functional evolution of new mammalian genes has been little explored at a broad scale. Previous work established mRNA-derived gene duplicates, known as retrocopies, as models for the study of new gene origination. Here we combine mammalian transcriptomic and epigenomic data to unveil the processes underlying the evolution of stripped-down retrocopies into complex new genes. We show that although some robustly expressed retrocopies are transcribed from preexisting promoters, most evolved new promoters from scratch or recruited proto-promoters in their genomic vicinity. In particular, many retrocopy promoters emerged from ancestral enhancers (or bivalent regulatory elements) or are located in CpG islands not associated with other genes. We detected 88-280 selectively preserved retrocopies per mammalian species, illustrating that these mechanisms facilitated the birth of many functional retrogenes during mammalian evolution. The regulatory evolution of originally monoexonic retrocopies was frequently accompanied by exon gain, which facilitated co-option of distant promoters and allowed expression of alternative isoforms. While young retrogenes are often initially expressed in the testis, increased regulatory and structural complexities allowed retrogenes to functionally diversify and evolve somatic organ functions, sometimes as complex as those of their parents. Thus, some retrogenes evolved the capacity to temporarily substitute for their parents during the process of male meiotic X inactivation, while others rendered parental functions superfluous, allowing for parental gene loss. Overall, our reconstruction of the "life history" of mammalian retrogenes highlights retroposition as a general model for understanding new gene birth and functional evolution.


Assuntos
Evolução Molecular , Mamíferos/genética , Retroelementos , Animais , Biologia Computacional/métodos , Epigênese Genética , Perfilação da Expressão Gênica , Genes , Humanos , Anotação de Sequência Molecular , Filogenia , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Transcriptoma , Vertebrados/genética
12.
Proc Biol Sci ; 286(1904): 20190884, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31161904

RESUMO

Bitter taste enables the detection of potentially harmful substances and is mediated by bitter taste receptors, TAS2Rs, in vertebrates. Few antagonists and inverse agonists of TAS2Rs have been identified, especially natural compounds. TAS2R16s in humans, apes and Old World monkeys (Catarrhini, Anthropoidea) recognize ß-glucoside analogues as specific agonists. Here, we investigated responses of TAS2R16 to ß-glucosides in non-anthropoid primates, namely lemurs (Lemuriformes, Strepsirrhini). Salicin acted as an agonist on lemur TAS2R16. Arbutin acted as an agonist in the ring-tailed lemur ( Lemur catta) but as an inverse agonist in black lemur ( Eulemur macaco) and black-and-white ruffed lemur ( Varecia variegata). We identified a strepsirrhine-specific amino acid substitution responsible for the inverse agonism of arbutin. In a food preference test, salicin bitterness was inhibited by arbutin in the black lemur. Structural modelling revealed this locus was important for a rearrangement of the intracellular end of transmembrane helix 7 (TM7). Accordingly, arbutin is the first known natural inverse agonist of TAS2Rs, contributing to our understanding of receptor-ligand interactions and the molecular basis of the unique feeding habit diversification in lemurs. Furthermore, the identification of a causal point mutation suggests that TAS2R can acquire functional changes according to feeding habits and environmental conditions.


Assuntos
Arbutina/química , Lemur/genética , Mutação Puntual , Receptores Acoplados a Proteínas G/genética , Paladar/genética , Substituição de Aminoácidos , Animais , Comportamento Alimentar , Preferências Alimentares , Lemur/fisiologia , Receptores Acoplados a Proteínas G/agonistas
13.
Biosci Biotechnol Biochem ; 83(9): 1766-1773, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31056002

RESUMO

In Experiment 1, the effects of calcium maltobionate (MBCa) on calcium and magnesium absorption were examined using male rats. Four diets were designed in which 25%, 50%, and 100% of calcium carbonate (CaCO3, Control) were substituted with MBCa and were designated as MBCa-25, MBCa-50, and MBCa-100, respectively. The cecal concentration of short-chain fatty acids was significantly higher in groups MBCa-50 and MBCa-100; however, pH of cecal contents did not significantly differ among the groups. Retention rates of calcium and magnesium were significantly higher in all MBCa groups as compared to the Control. In Experiment 2, the efficiency of calcium absorption was compared using everted sacs of jejunum and ileum with CaCO3 and MBCa as calcium sources. More calcium from MBCa was absorbed as the concentration of calcium increased in comparison to CaCO3. It was concluded that MBCa is a better calcium source than CaCO3 in terms of both calcium retention and absorption. Abbreviations: ANOVA: analysis of variance; Ca: Calcium; CaCO3: calcium carbonate; ICP-OES: Inductivity coupled plasma optical emission spectrometer; Mg: magnesium; MBCa: calcium maltobionate; OCPC: o-cresolphthalein complexone; SCFAs: short-chain fatty acids; SE: standard error; TRPM6: transient receptor potential melastatin 6.


Assuntos
Cálcio/metabolismo , Dissacarídeos/farmacologia , Absorção Intestinal/efeitos dos fármacos , Magnésio/metabolismo , Animais , Carbonato de Cálcio/administração & dosagem , Ceco/metabolismo , Dieta , Ácidos Graxos Voláteis/metabolismo , Concentração de Íons de Hidrogênio , Íleo/efeitos dos fármacos , Íleo/metabolismo , Jejuno/efeitos dos fármacos , Jejuno/metabolismo , Masculino , Ratos , Ratos Wistar , Solubilidade
14.
Am J Primatol ; 81(12): e23072, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31788810

RESUMO

In recent decades, human-wildlife interaction and associated anthropogenic food provisioning has been increasing and becoming more severe due to fast population growth and urban development. Noting the role of the gut microbiome in host physiology like nutrition and health, it is thus essential to understand how human-wildlife interactions and availability of anthropogenic food in habitats can affect an animal's gut microbiome. This study, therefore, set out to examine the gut microbiota of Japanese macaques (Macaca fuscata) with varying accessibility to anthropogenic food and the possibility of using gut microbiota as indicator for macaques' reliance on anthropogenic food. Using 16S ribosomal RNA gene sequencing, we described the microbial composition of Japanese macaques experiencing different types of human disturbance and anthropogenic food availability-captive, provisioned, crop-raiding, and wild. In terms of alpha diversity, our results showed that observed richness of gut microbiota did not differ significantly between disturbance types but among collection sites, whereas Shannon diversity index differed by both disturbance types and sites. In terms of beta diversity, captive populations harbored the most distinctive gut microbial composition, and had the greatest difference compared with wild populations. Whereas for provisioned and crop-raiding groups, the macaques exhibited intermediate microbiota between wild and captive. We identified several potential bacterial taxa at different taxonomic ranks whose abundance potentially could help in assessing macaques' accessibility to anthropogenic food. This study revealed the flexibility of the gut microbiome of Japanese macaques and provided possible indices based on the gut microbiome profile in assessing macaques' accessibility to/reliance on anthropogenic foods.


Assuntos
Dieta/veterinária , Comportamento Alimentar , Microbioma Gastrointestinal , Macaca fuscata/microbiologia , Animais , RNA Bacteriano/análise , RNA Ribossômico 16S/análise
15.
Biol Lett ; 13(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28123110

RESUMO

Bitterness perception in mammals is mostly directed at natural toxins that induce innate avoidance behaviours. Bitter taste is mediated by the G protein-coupled receptor TAS2R, which is located in taste cell membranes. One of the best-studied bitter taste receptors is TAS2R38, which recognizes phenylthiocarbamide (PTC). Here we investigate the sensitivities of TAS2R38 receptors to PTC in four species of leaf-eating monkeys (subfamily Colobinae). Compared with macaque monkeys (subfamily Cercopithecinae), colobines have lower sensitivities to PTC in behavioural and in vitro functional analyses. We identified four non-synonymous mutations in colobine TAS2R38 that are responsible for the decreased sensitivity of the TAS2R38 receptor to PTC observed in colobines compared with macaques. These results suggest that tolerance to bitterness in colobines evolved from an ancestor that was sensitive to bitterness as an adaptation to eating leaves.


Assuntos
Colobinae/fisiologia , Macaca/fisiologia , Feniltioureia , Receptores Acoplados a Proteínas G/genética , Paladar/genética , Animais , Evolução Biológica , Colobinae/genética , Células HEK293 , Humanos , Macaca/genética , Malus , Análise de Sequência de Proteína
16.
Biosci Biotechnol Biochem ; 81(2): 316-322, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27696964

RESUMO

We investigated the efficacy of supplementing the diet with choline or betaine in ameliorating lipid accumulation induced by vitamin B6 (B6) deficiency in rat liver. Male Wistar rats were fed a control, B6-deficient, choline-supplemented (2, 4, or 6 g choline bitartrate/kg diet) B6-deficient diet or betaine-supplemented (1, 2, or 4 g betaine anhydrous/kg diet) B6-deficient diet for 35 d; all diets contained 9 g L-methionine (Met)/kg diet. Choline or betaine supplementation attenuated liver lipid deposition and restored plasma lipid profiles to control levels. These treatments restored the disruptions in Met metabolism and the phosphatidylcholine (PC)/phosphatidylethanolamine (PE) ratio induced by B6 deficiency in liver microsomes. These results suggest that choline and betaine ameliorated liver lipid accumulation induced by B6 deficiency via recovery of Met metabolism and very low-density lipoprotein secretion by restoring the supply of PC derived from PE.


Assuntos
Betaína/farmacologia , Colina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Deficiência de Vitamina B 6/metabolismo , Animais , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Homocisteína/sangue , Homocisteína/metabolismo , Masculino , Fosfatidilcolinas/biossíntese , Fosfatidilcolinas/sangue , Fosfatidilcolinas/metabolismo , Ratos , Ratos Wistar , Vitamina B 6/sangue , Vitamina B 6/metabolismo , Deficiência de Vitamina B 6/sangue
17.
Biosci Biotechnol Biochem ; 81(4): 803-811, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28118791

RESUMO

Mayonnaise-like oil-in-water emulsions with different stabilities-evaluated from the degree of macroscopic defects, e.g., syneresis-were prepared by different formulations and processing conditions (egg yolk weight, homogenizer speed, and vegetable oil temperature). Emulsions prepared with lower egg yolk content were destabilized for shorter periods. The long-term stability of emulsions was weakly related to initial properties, e.g., oil droplet distribution and protein coverage at the interface. Protein aggregation between oil droplets was observed and would be responsible for the instability of emulsions exhibited by the appearance defects. SDS-PAGE results for adsorbed and unadsorbed proteins at the O/W interface suggested that predominant constituents adsorbed onto the interface were egg white proteins as compared with egg yolk components when the amount of added egg yolk was low. In present condition, egg white proteins adsorbed at the O/W interface could be a bridge of neighboring oil droplets thereby causing flocculation in emulsions.


Assuntos
Emulsões/química , Manipulação de Alimentos , Óleos de Plantas/química , Adsorção , Ovos , Tamanho da Partícula , Temperatura , Água/química
18.
BMC Evol Biol ; 16(1): 208, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733116

RESUMO

BACKGROUND: New World monkeys (NWMs) are unique in that they exhibit remarkable interspecific variation in color vision and feeding behavior, making them an excellent model for studying sensory ecology. However, it is largely unknown whether non-visual senses co-vary with feeding ecology, especially gustation, which is expected to be indispensable in food selection. Bitter taste, which is mediated by bitter taste receptors (TAS2Rs) in the tongue, helps organisms avoid ingesting potentially toxic substances in food. In this study, we compared the ligand sensitivities of the TAS2Rs of five species of NWMs by heterologous expression in HEK293T cells and calcium imaging. RESULTS: We found that TAS2R1 and TAS2R4 orthologs differ in sensitivity among the NWM species for colchicine and camphor, respectively. We then reconstructed the ancestral receptors of NWM TAS2R1 and TAS2R4, measured the evolutionary shift in ligand sensitivity, and identified the amino acid replacement at residue 62 as responsible for the high sensitivity of marmoset TAS2R4 to colchicine. CONCLUSIONS: Our results provide a basis for understanding the differences in feeding ecology among NWMs with respect to bitter taste.


Assuntos
Platirrinos/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Paladar , Animais , Evolução Molecular , Células HEK293 , Humanos , Filogenia , Platirrinos/classificação , Polimorfismo de Nucleotídeo Único , Receptores Acoplados a Proteínas G/química , Especificidade da Espécie
19.
Biosci Biotechnol Biochem ; 80(10): 1995-2000, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27296718

RESUMO

The effect of resistant starch (RS) and konjac mannan (KM) to maintain and improve the large intestinal environment was compared. Wistar SPF rats were fed the following diets for 4 weeks: negative control diet (C diet), tyrosine-supplemented positive control diet (T diet), and luminacoid supplemented diets containing either high-molecular konjac mannan A (KMAT diet), low-molecular konjac mannan B (KMBT diet), high-amylose cornstarch (HAST diet), or heat-moisture-treated starch (HMTST diet). The luminacoid-fed group had an increased content of short-chain fatty acids in the cecum. HAS caused a significant decrease in p-cresol content in the cecum, whereas KM did not. Urinary p-cresol was reduced in the HAST group compared with the T group, but not the KM fed groups. Deterioration in the large intestinal environment was only improved completely in the HAST and HMTST groups, suggesting that RS is considerably more effective than KM in maintaining the large intestinal environment.


Assuntos
Ceco/efeitos dos fármacos , Ceco/metabolismo , Cresóis/urina , Suplementos Nutricionais , Amido/farmacologia , Tirosina/farmacologia , Animais , Ceco/crescimento & desenvolvimento , Cresóis/metabolismo , Ácidos Graxos/metabolismo , Masculino , Mananas/farmacologia , Tamanho do Órgão/efeitos dos fármacos , Fenol/metabolismo , Ratos , Ratos Wistar , Amido/metabolismo
20.
Mol Biol Evol ; 31(8): 2018-31, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24758778

RESUMO

Genome studies of mammals in the superorder Euarchontoglires (a clade that comprises the orders Primates, Dermoptera, Scandentia, Rodentia, and Lagomorpha) are important for understanding the biological features of humans, particularly studies of medical model animals such as macaques and mice. Furthermore, the dynamic ecoevolutionary signatures of Euarchontoglires genomes may be discovered because many species in this clade are characterized by their successful adaptive radiation to various ecological niches. In this study, we investigated the evolutionary trajectory of bitter taste receptor genes (TAS2Rs) in 28 Euarchontoglires species based on homology searches of 39 whole-genome assemblies. The Euarchontoglires species possessed variable numbers of intact TAS2Rs, which ranged from 16 to 40, and their last common ancestor had at least 26 intact TAS2Rs. The gene tree showed that there have been at least seven lineage-specific events involving massive gene duplications. Gene duplications were particularly evident in the ancestral branches of anthropoids (the anthropoid cluster), which may have promoted the adaptive evolution of anthropoid characteristics, such as a trade-off between olfaction and other senses and the development of herbivorous characteristics. Subsequent whole-gene deletions of anthropoid cluster TAS2Rs in hominoid species suggest ongoing ectopic homologous recombination in the anthropoid cluster. These findings provide insights into the roles of adaptive sensory evolution in various ecological niches and important clues related to the molecular mechanisms that underlie taste diversity in Euarchontoglires mammalian species, including humans.


Assuntos
Genômica/métodos , Mamíferos/classificação , Mamíferos/genética , Receptores Acoplados a Proteínas G/genética , Paladar , Animais , Evolução Molecular , Deleção de Genes , Duplicação Gênica , Humanos , Filogenia , Homologia de Sequência , Especificidade da Espécie
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