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  1. Artikel ; Online: Duplication and diversification of insulin genes in ray-finned fish

    David M. Irwin

    Zoological Research, Vol 40, Iss 3, Pp 185-

    2019  Band 197

    Abstract: Insulin is a key hormone for the regulation of metabolism in vertebrates. Insulin is produced by pancreatic islet cells in response to elevated glucose levels and leads to the uptake of glucose by tissues such as liver and adipose tissue to store energy. ...

    Abstract Insulin is a key hormone for the regulation of metabolism in vertebrates. Insulin is produced by pancreatic islet cells in response to elevated glucose levels and leads to the uptake of glucose by tissues such as liver and adipose tissue to store energy. Insulin also has additional functions in regulating development. Previous work has shown that the proglucagon gene, which encodes hormones counter regulating insulin, is duplicated in teleost fish, and that the peptide hormones encoded by these genes have diversified in function. I sought to determine whether similar processes have occurred to insulin genes in these species. Searches of fish genomes revealed an unexpected diversity of insulin genes. A triplication of the insulin gene occurred at the origin of teleost fish, however one of these three genes, insc, has been lost in most teleost fish lineages. The two other insulin genes, insa and insb, have been retained but show differing levels of selective constraint suggesting that they might have diversified in function. Intriguingly, a duplicate copy of the insa gene, which I named insab, is found in many fish. The coding sequence encoded by insab genes is under weak selective constraint, with its predicted protein sequences losing their potential to be processed into a two-peptide hormone. However, these sequences have retained perfectly conserved cystine residues, suggesting that they maintain insulin’s three-dimensional structure and therefore might modulate the processing and secretion of insulin produced by the other genes.
    Schlagwörter Insulin ; Teleost fish ; Gene duplication ; Adaptive evolution ; Gene loss ; Zoology ; QL1-991
    Thema/Rubrik (Code) 612
    Sprache Englisch
    Erscheinungsdatum 2019-05-01T00:00:00Z
    Verlag Science Press, PR China
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel ; Online: Accelerated evolution of dim-light vision-related arrestin in deep-diving amniotes

    Xin Guo / Yimeng Cui / David M. Irwin / Yang Liu

    Frontiers in Ecology and Evolution, Vol

    2022  Band 10

    Abstract: Arrestins are key molecules involved in the signaling of light-sensation initiated by visual pigments in retinal photoreceptor cells. Vertebrate photoreceptor cells have two types of arrestins, rod arrestin, which is encoded by SAG and is expressed in ... ...

    Abstract Arrestins are key molecules involved in the signaling of light-sensation initiated by visual pigments in retinal photoreceptor cells. Vertebrate photoreceptor cells have two types of arrestins, rod arrestin, which is encoded by SAG and is expressed in both rods and cones, and cone arrestin, encoded by ARR3 in cones. The arrestins can bind to visual pigments, and thus regulate either dim-light vision via interactions with rhodopsin or bright-light vision together with cone visual pigments. After adapting to terrestrial life, several amniote lineages independently went back to the sea and evolved deep-diving habits. Interestingly, the rhodopsins in these species exhibit specialized phenotypes responding to rapidly changing dim-light environments. However, little is known about whether their rod arrestin also experienced adaptive evolution associated with rhodopsin. Here, we collected SAG coding sequences from >250 amniote species, and examined changes in selective pressure experienced by the sequences from deep-diving taxa. Divergent patterns of evolution of SAG were observed in the penguin, pinniped and cetacean clades, suggesting possible co-adaptation with rhodopsin. After verifying pseudogenes, the same analyses were performed for cone arrestin (ARR3) in deep-diving species and only sequences from cetacean species, and not pinnipeds or penguins, have experienced changed selection pressure compared to other species. Taken together, this evidence for changes in selective pressures acting upon arrestin genes strengthens the suggestion that rapid dim-light adaptation for deep-diving amniotes require SAG, but not ARR3.
    Schlagwörter vertebrates ; SAG ; ARR3 ; scotopic vision ; molecular evolution ; visual adaptation ; Evolution ; QH359-425 ; Ecology ; QH540-549.5
    Thema/Rubrik (Code) 580
    Sprache Englisch
    Erscheinungsdatum 2022-12-01T00:00:00Z
    Verlag Frontiers Media S.A.
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  3. Artikel ; Online: Genomic organization and evolution of ruminant lysozyme c genes

    David M. IRWIN

    Zoological Research, Vol 36, Iss 1, Pp 1-

    2015  Band 17

    Abstract: Ruminant stomach lysozyme is a long established model of adaptive gene evolution. Evolution of stomach lysozyme function required changes in the site of expression of the lysozyme c gene and changes in the enzymatic properties of the enzyme. In ruminant ... ...

    Abstract Ruminant stomach lysozyme is a long established model of adaptive gene evolution. Evolution of stomach lysozyme function required changes in the site of expression of the lysozyme c gene and changes in the enzymatic properties of the enzyme. In ruminant mammals, these changes were associated with a change in the size of the lysozyme c gene family. The recent release of near complete genome sequences from several ruminant species allows a more complete examination of the evolution and diversification of the lysozyme c gene family. Here we characterize the size of the lysozyme c gene family in extant ruminants and demonstrate that their pecoran ruminant ancestor had a family of at least 10 lysozyme c genes, which included at least two pseudogenes. Evolutionary analysis of the ruminant lysozyme c gene sequences demonstrate that each of the four exons of the lysozyme c gene has a unique evolutionary history, indicating that they participated independently in concerted evolution. These analyses also show that episodic changes in the evolutionary constraints on the protein sequences occurred, with lysozyme c genes expressed in the abomasum of the stomach of extant ruminant species showing the greatest levels of selective constraints.
    Schlagwörter Lysozyme c ; Ruminants ; Gene family ; Gene duplication ; Concerted evolution ; Mosaic evolution ; Zoology ; QL1-991
    Thema/Rubrik (Code) 572
    Sprache Englisch
    Erscheinungsdatum 2015-01-01T00:00:00Z
    Verlag Science Press, PR China
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel ; Online: Contrasting Patterns in the Evolution of Vertebrate MLX Interacting Protein (MLXIP) and MLX Interacting Protein-Like (MLXIPL) Genes.

    Parmveer Singh / David M Irwin

    PLoS ONE, Vol 11, Iss 2, p e

    2016  Band 0149682

    Abstract: ChREBP and MondoA are glucose-sensitive transcription factors that regulate aspects of energy metabolism. Here we performed a phylogenomic analysis of Mlxip (encoding MondoA) and Mlxipl (encoding ChREBP) genes across vertebrates. Analysis of extant Mlxip ...

    Abstract ChREBP and MondoA are glucose-sensitive transcription factors that regulate aspects of energy metabolism. Here we performed a phylogenomic analysis of Mlxip (encoding MondoA) and Mlxipl (encoding ChREBP) genes across vertebrates. Analysis of extant Mlxip and Mlxipl genes suggests that the most recent common ancestor of these genes was composed of 17 coding exons. Single copy genes encoding both ChREBP and MondoA, along with their interacting partner Mlx, were found in diverse vertebrate genomes, including fish that have experienced a genome duplication. This observation suggests that a single Mlx gene has been retained to maintain coordinate regulation of ChREBP and MondoA. The ChREBP-β isoform, the more potent and constitutively active isoform, appeared with the evolution of tetrapods and is absent from the Mlxipl genes of fish. Evaluation of the conservation of ChREBP and MondoA sequences demonstrate that MondoA is better conserved and potentially mediates more ancient function in glucose metabolism.
    Schlagwörter Medicine ; R ; Science ; Q
    Thema/Rubrik (Code) 612
    Sprache Englisch
    Verlag Public Library of Science (PLoS)
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  5. Artikel ; Online: Adaptive Evolution of the Fox Coronavirus Based on Genome-Wide Sequence Analysis

    Chunyu Feng / Yuting Liu / Guangqi Lyu / Songyang Shang / Hongyue Xia / Junpeng Zhang / David M. Irwin / Zhe Wang / Shuyi Zhang

    BioMed Research International, Vol

    2022  Band 2022

    Abstract: Purpose. To report the first complete fox coronavirus (CoV) genome sequence obtained through genome-wide amplifications and to understand the adaptive evolution of fox CoV. Methods. Anal swab samples were collected from 35 foxes to detect the presence of ...

    Abstract Purpose. To report the first complete fox coronavirus (CoV) genome sequence obtained through genome-wide amplifications and to understand the adaptive evolution of fox CoV. Methods. Anal swab samples were collected from 35 foxes to detect the presence of CoV and obtain the virus sequence. Phylogenetic analysis was conducted using MrBayes. The possibility of recombination within these sequences was assessed using GARD. Analysis of the levels of selection pressure experienced by these sequences was assessed using methods on both the PAML and Data Monkey platforms. Results. Of the 35 samples, two were positive, and complete genome sequences for the viruses were obtained. Phylogenetic analysis, using Bayesian methods, of these sequences, together with other CoV sequences, revealed that the fox CoV sequences clustered with canine coronavirus (CCoV) sequences, with sequences from other carnivores more distantly related. In contrast to the feline, ferret and mink CoV sequences that clustered into species-specific clades, the fox CoV fell within the CCoV clade. Minimal evidence for recombination was found among the sequences. A total of 7, 3, 14, and 2 positively selected sites were identified in the M, N, S, and 7B genes, respectively, with 99, 111, and 581 negatively selected sites identified in M, N, and S genes, respectively. Conclusion. The complete genome sequence of fox CoV has been obtained for the first time. The results suggest that the genome sequence of fox CoV may have experienced adaptive evolution in the genes replication, entry, and virulence. The number of sites in each gene that experienced negative selection is far greater than the number that underwent positive selection, suggesting that most of the sequence is highly conserved and important for viral survive. However, positive selection at a few sites likely aided these viruses to adapt to new environments.
    Schlagwörter Medicine ; R
    Thema/Rubrik (Code) 572
    Sprache Englisch
    Erscheinungsdatum 2022-01-01T00:00:00Z
    Verlag Hindawi Limited
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  6. Artikel ; Online: Evolution of the Vertebrate Resistin Gene Family.

    Qingda Hu / Huanran Tan / David M Irwin

    PLoS ONE, Vol 10, Iss 6, p e

    2015  Band 0130188

    Abstract: Resistin (encoded by Retn) was previously identified in rodents as a hormone associated with diabetes; however human resistin is instead linked to inflammation. Resistin is a member of a small gene family that includes the resistin-like peptides (encoded ...

    Abstract Resistin (encoded by Retn) was previously identified in rodents as a hormone associated with diabetes; however human resistin is instead linked to inflammation. Resistin is a member of a small gene family that includes the resistin-like peptides (encoded by Retnl genes) in mammals. Genomic searches of available genome sequences of diverse vertebrates and phylogenetic analyses were conducted to determine the size and origin of the resistin-like gene family. Genes encoding peptides similar to resistin were found in Mammalia, Sauria, Amphibia, and Actinistia (coelacanth, a lobe-finned fish), but not in Aves or fish from Actinopterygii, Chondrichthyes, or Agnatha. Retnl originated by duplication and transposition from Retn on the early mammalian lineage after divergence of the platypus, but before the placental and marsupial mammal divergence. The resistin-like gene family illustrates an instance where the locus of origin of duplicated genes can be identified, with Retn continuing to reside at this location. Mammalian species typically have a single copy Retn gene, but are much more variable in their numbers of Retnl genes, ranging from 0 to 9. Since Retn is located at the locus of origin, thus likely retained the ancestral expression pattern, largely maintained its copy number, and did not display accelerated evolution, we suggest that it is more likely to have maintained an ancestral function, while Retnl, which transposed to a new location, displays accelerated evolution, and shows greater variability in gene number, including gene loss, likely evolved new, but potentially lineage-specific, functions.
    Schlagwörter Medicine ; R ; Science ; Q
    Thema/Rubrik (Code) 572
    Sprache Englisch
    Erscheinungsdatum 2015-01-01T00:00:00Z
    Verlag Public Library of Science (PLoS)
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  7. Artikel ; Online: Hen raising helps chicks establish gut microbiota in their early life and improve microbiota stability after H9N2 challenge

    Xiaobing Li / Ran Bi / Kangpeng Xiao / Ayan Roy / Zhipeng Zhang / Xiaoyuan Chen / Jinyu Peng / Ruichen Wang / Rou Yang / Xuejuan Shen / David M. Irwin / Yongyi Shen

    Microbiome, Vol 10, Iss 1, Pp 1-

    2022  Band 12

    Abstract: Abstract Background Early gut microbial colonization is important for postnatal growth and immune development of the chicken. However, at present, commercial chickens are hatched and raised without adult hens, thus are cut off from the microbiota ... ...

    Abstract Abstract Background Early gut microbial colonization is important for postnatal growth and immune development of the chicken. However, at present, commercial chickens are hatched and raised without adult hens, thus are cut off from the microbiota transfer between hens and chicks. In this study, we compared the gut microbiota composition between hen-reared and separately reared chicks, and its impact on the resistance to H9N2 avian influenza virus, with the motive of investigating the impact of this cutoff in microbiota transfer. Results We used the 16SrRNA sequencing method to assess the composition of the gut microbiota in chicks represented by three hen-reared groups and one separately reared group. We found that the diversity of gut microbes in the chicks from the three hen-reared groups was more abundant than in the separately reared group, both at the phylum and genus levels. Our findings highlight the importance of early parental care in influencing the establishment of gut microbiota in the early life of chicks. SourceTracker analysis showed that the feather and cloaca microbiota of hens are the main sources of gut microbiota of chicks. After H9N2 exposure, the viral infection lasted longer in the separately reared chicks, with the viral titers in their oropharyngeal swabs being higher compared to the hen-reared chicks at day 5 post-infection. Interestingly, our results revealed that the gut microbiota of the hen-reared chicks was more stable after H9N2 infection in comparison to that of the separately reared chicks. Conclusions Microbiota transfer between the hens and their chicks promotes the establishment of a balanced and diverse microbiota in the early life of the chicks and improves microbiota stability after H9N2 challenge. These findings advance our understanding of the protective role of gut microbiota in the early life of chicks and should be instrumental in improving chick rearing in the commercial poultry industry. Video Abstract
    Schlagwörter Gut microbiota ; Maternal microbial transmission ; H9N2 avian influenza virus ; Disease resistance ; Microbial ecology ; QR100-130
    Thema/Rubrik (Code) 900
    Sprache Englisch
    Erscheinungsdatum 2022-01-01T00:00:00Z
    Verlag BMC
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  8. Artikel ; Online: Adaptive Evolution of Feline Coronavirus Genes Based on Selection Analysis

    Hongyue Xia / Xibao Li / Wenliang Zhao / Shuran Jia / Xiaoqing Zhang / David M. Irwin / Shuyi Zhang

    BioMed Research International, Vol

    2020  Band 2020

    Abstract: Purpose. We investigated sequences of the feline coronaviruses (FCoV), which include feline enteric coronavirus (FECV) and feline infectious peritonitis virus (FIPV), from China and other countries to gain insight into the adaptive evolution of this ... ...

    Abstract Purpose. We investigated sequences of the feline coronaviruses (FCoV), which include feline enteric coronavirus (FECV) and feline infectious peritonitis virus (FIPV), from China and other countries to gain insight into the adaptive evolution of this virus. Methods. Ascites samples from 31 cats with suspected FIP and feces samples from 8 healthy cats were screened for the presence of FCoV. Partial viral genome sequences, including parts of the nsp12-nsp14, S, N, and 7b genes, were obtained and aligned with additional sequences obtained from the GenBank database. Bayesian phylogenetic analysis was conducted, and the possibility of recombination within these sequences was assessed. Analysis of the levels of selection pressure experienced by these sequences was assessed using methods on both the PAML and Datamonkey platforms. Results. Of the 31 cats investigated, two suspected FIP cats and one healthy cat tested positive for FCoV. Phylogenetic analysis showed that all of the sequences from mainland China cluster together with a few sequences from the Netherlands as a distinct clade when analyzed with FCoV sequences from other countries. Fewer than 3 recombination breakpoints were detected in the nsp12-nsp14, S, N, and 7b genes, suggesting that analyses for positive selection could be conducted. A total of 4, 12, 4, and 4 positively selected sites were detected in the nsp12-nsp14, S, N, and 7b genes, respectively, with the previously described site 245 of the S gene, which distinguishes FIPV from FECV, being a positive selection site. Conversely, 106, 168, 25, and 17 negative selection sites in the nsp12-14, S, N, and 7b genes, respectively, were identified. Conclusion. Our study provides evidence that the FCoV genes encoding replicative, entry, and virulence proteins potentially experienced adaptive evolution. A greater number of sites in each gene experienced negative rather than positive selection, which suggests that most of the protein sequence must be conservatively maintained for virus survival. A few of the ...
    Schlagwörter Medicine ; R
    Thema/Rubrik (Code) 572
    Sprache Englisch
    Erscheinungsdatum 2020-01-01T00:00:00Z
    Verlag Hindawi Limited
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  9. Artikel: Genome-wide identification and characterization of teleost-specific microRNAs within zebrafish

    Yang, Liandong / David M. Irwin / Shunping He

    Gene. 2015 May 01, v. 561

    2015  

    Abstract: The molecular genetic basis of teleost phenotypic diversity remains poorly understood, despite the increasing availability of genome and transcriptome data. Changes in gene expression, resulting from regulatory mutations, contribute to many or even most ... ...

    Abstract The molecular genetic basis of teleost phenotypic diversity remains poorly understood, despite the increasing availability of genome and transcriptome data. Changes in gene expression, resulting from regulatory mutations, contribute to many or even most phenotypic innovations. In this study, we performed comparative genomic analyses to identify 44 Conserved Teleost-Specific MicroRNAs (CTSMs). An analysis of the sequences of CTSMs demonstrated that their sequence variability is significantly higher than that of Evolutionarily Conserved microRNAs (ECs — microRNAs conserved throughout vertebrates), and that this difference primarily results from variation in the loop regions. We computationally predicted target genes for CTSMs and found that the targets of CTSMs show significantly lower SNP density compared with targets of ECs as well as non-targets of CTSMs. The temporal expression profile of targets of CTSMs obtained from RNA-seq data revealed that the targets of CTSMs are specifically enriched in early-stage embryos and exhibit a broader expression spectrum. Finally, functional enrichment analysis (GO and KEGG) indicated that the targets of CTSMs play diverse functional roles, with a significantly enriched category being the “immune response”. Our study provides the first systematic identification and characterization of conserved teleost-specific microRNAs and their targets and presents valuable foundation for a better understanding the genomic basis for the diversification of teleosts.
    Schlagwörter Danio rerio ; gene expression regulation ; genes ; genetic variation ; immune response ; microRNA ; phenotype ; phenotypic variation ; sequence analysis ; single nucleotide polymorphism ; transcriptome ; vertebrates
    Sprache Englisch
    Erscheinungsverlauf 2015-0501
    Umfang p. 181-189.
    Erscheinungsort Elsevier B.V.
    Dokumenttyp Artikel
    ZDB-ID 391792-7
    ISSN 1879-0038 ; 0378-1119
    ISSN (online) 1879-0038
    ISSN 0378-1119
    DOI 10.1016/j.gene.2015.02.055
    Datenquelle NAL Katalog (AGRICOLA)

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  10. Artikel ; Online: Phosphoenolpyruvate carboxykinase 1 gene (Pck1) displays parallel evolution between Old World and New World fruit bats.

    Lei Zhu / Qiuyuan Yin / David M Irwin / Shuyi Zhang

    PLoS ONE, Vol 10, Iss 3, p e

    2015  Band 0118666

    Abstract: Bats are an ideal mammalian group for exploring adaptations to fasting due to their large variety of diets and because fasting is a regular part of their life cycle. Mammals fed on a carbohydrate-rich diet experience a rapid decrease in blood glucose ... ...

    Abstract Bats are an ideal mammalian group for exploring adaptations to fasting due to their large variety of diets and because fasting is a regular part of their life cycle. Mammals fed on a carbohydrate-rich diet experience a rapid decrease in blood glucose levels during a fast, thus, the development of mechanisms to resist the consequences of regular fasts, experienced on a daily basis, must have been crucial in the evolution of frugivorous bats. Phosphoenolpyruvate carboxykinase 1 (PEPCK1, encoded by the Pck1 gene) is the rate-limiting enzyme in gluconeogenesis and is largely responsible for the maintenance of glucose homeostasis during fasting in fruit-eating bats. To test whether Pck1 has experienced adaptive evolution in frugivorous bats, we obtained Pck1 coding sequence from 20 species of bats, including five Old World fruit bats (OWFBs) (Pteropodidae) and two New World fruit bats (NWFBs) (Phyllostomidae). Our molecular evolutionary analyses of these sequences revealed that Pck1 was under purifying selection in both Old World and New World fruit bats with no evidence of positive selection detected in either ancestral branch leading to fruit bats. Interestingly, however, six specific amino acid substitutions were detected on the ancestral lineage of OWFBs. In addition, we found considerable evidence for parallel evolution, at the amino acid level, between the PEPCK1 sequences of Old World fruit bats and New World fruit bats. Test for parallel evolution showed that four parallel substitutions (Q276R, R503H, I558V and Q593R) were driven by natural selection. Our study provides evidence that Pck1 underwent parallel evolution between Old World and New World fruit bats, two lineages of mammals that feed on a carbohydrate-rich diet and experience regular periods of fasting as part of their life cycle.
    Schlagwörter Medicine ; R ; Science ; Q
    Thema/Rubrik (Code) 590
    Sprache Englisch
    Erscheinungsdatum 2015-01-01T00:00:00Z
    Verlag Public Library of Science (PLoS)
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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