Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution
Elemental stoichiometry defines a critical understanding of the relationship between nutrient availability and usage throughout different levels of the biological community. We found there is a link between available phosphorus (P), cellular phosphorus, and nematode development as postulated by the...
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ftbrighamyoung:oai:scholarsarchive.byu.edu:etd-8422 2023-07-23T04:14:13+02:00 Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution Xue, Xia 2018-06-01T07:00:00Z application/pdf https://scholarsarchive.byu.edu/etd/7422 https://scholarsarchive.byu.edu/context/etd/article/8422/viewcontent/etd10062.pdf unknown BYU ScholarsArchive https://scholarsarchive.byu.edu/etd/7422 https://scholarsarchive.byu.edu/context/etd/article/8422/viewcontent/etd10062.pdf http://lib.byu.edu/about/copyright/ Theses and Dissertations Antarctic nematodes Caenorhabditis elegans genome evolution growth rate hypothesis Plectus murrayi Scottnema lindsayae transcriptome Life Sciences text 2018 ftbrighamyoung 2023-07-03T22:42:50Z Elemental stoichiometry defines a critical understanding of the relationship between nutrient availability and usage throughout different levels of the biological community. We found there is a link between available phosphorus (P), cellular phosphorus, and nematode development as postulated by the growth rate hypothesis (GRH). I predicted that in a P-poor environment, cellular RNA concentrations would be lower than they are in P-rich environment, and thus the 18s rRNA expression level will have reduced. To most efficiently regulate the uptake of limited P, I predicted that nematodes in P-poor environments would decrease the number of copies of the 18s rRNA gene in their genome. I measured life history traits as well as rRNA gene expression and gene copy number. We found that elemental stoichiometry predicts evolutionary changes consistent with the Growth Rate Hypothesis. We sequenced and assembled a draft genome of P. murrayi. Although we expected to find genes responsible for stress tolerance, we hypothesized that in response to strong selection pressure associated with living in a simplified ecosystem, over time the genome of P. murrayi should have undergone significant decay (gene loss) relative to species in ecosystems structured more strongly by biotic interactions. We found significantly fewer genes in P. murrayi. To compare patterns of gene expression between two highly divergent Antarctic nematode species, we sequenced and assembled the transcriptomes of S. lindsayae and P. murrayi. Under laboratory conditions at 4˚C, S. lindsayae had significantly lower rates of gene expression but expressed a significantly larger number of genes. We speculate that the differences in gene expression are correlated with life history traits (developmental rates) while the differences in the number of genes expressed can be explained by their different genetic systems (S. lindsayae is amphimictic, P. murrayi is parthenogenic) and the soil environments to which they are adapted. Since we previously showed that differences ... Text Antarc* Antarctic Brigham Young University (BYU): ScholarsArchive Antarctic |
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Brigham Young University (BYU): ScholarsArchive |
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ftbrighamyoung |
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Antarctic nematodes Caenorhabditis elegans genome evolution growth rate hypothesis Plectus murrayi Scottnema lindsayae transcriptome Life Sciences |
spellingShingle |
Antarctic nematodes Caenorhabditis elegans genome evolution growth rate hypothesis Plectus murrayi Scottnema lindsayae transcriptome Life Sciences Xue, Xia Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
topic_facet |
Antarctic nematodes Caenorhabditis elegans genome evolution growth rate hypothesis Plectus murrayi Scottnema lindsayae transcriptome Life Sciences |
description |
Elemental stoichiometry defines a critical understanding of the relationship between nutrient availability and usage throughout different levels of the biological community. We found there is a link between available phosphorus (P), cellular phosphorus, and nematode development as postulated by the growth rate hypothesis (GRH). I predicted that in a P-poor environment, cellular RNA concentrations would be lower than they are in P-rich environment, and thus the 18s rRNA expression level will have reduced. To most efficiently regulate the uptake of limited P, I predicted that nematodes in P-poor environments would decrease the number of copies of the 18s rRNA gene in their genome. I measured life history traits as well as rRNA gene expression and gene copy number. We found that elemental stoichiometry predicts evolutionary changes consistent with the Growth Rate Hypothesis. We sequenced and assembled a draft genome of P. murrayi. Although we expected to find genes responsible for stress tolerance, we hypothesized that in response to strong selection pressure associated with living in a simplified ecosystem, over time the genome of P. murrayi should have undergone significant decay (gene loss) relative to species in ecosystems structured more strongly by biotic interactions. We found significantly fewer genes in P. murrayi. To compare patterns of gene expression between two highly divergent Antarctic nematode species, we sequenced and assembled the transcriptomes of S. lindsayae and P. murrayi. Under laboratory conditions at 4˚C, S. lindsayae had significantly lower rates of gene expression but expressed a significantly larger number of genes. We speculate that the differences in gene expression are correlated with life history traits (developmental rates) while the differences in the number of genes expressed can be explained by their different genetic systems (S. lindsayae is amphimictic, P. murrayi is parthenogenic) and the soil environments to which they are adapted. Since we previously showed that differences ... |
format |
Text |
author |
Xue, Xia |
author_facet |
Xue, Xia |
author_sort |
Xue, Xia |
title |
Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
title_short |
Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
title_full |
Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
title_fullStr |
Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
title_full_unstemmed |
Genomics and Transcriptomics of Antarctic Nematodes Reveal Drivers of Life History Evolution and Genome Evolution |
title_sort |
genomics and transcriptomics of antarctic nematodes reveal drivers of life history evolution and genome evolution |
publisher |
BYU ScholarsArchive |
publishDate |
2018 |
url |
https://scholarsarchive.byu.edu/etd/7422 https://scholarsarchive.byu.edu/context/etd/article/8422/viewcontent/etd10062.pdf |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Theses and Dissertations |
op_relation |
https://scholarsarchive.byu.edu/etd/7422 https://scholarsarchive.byu.edu/context/etd/article/8422/viewcontent/etd10062.pdf |
op_rights |
http://lib.byu.edu/about/copyright/ |
_version_ |
1772183534054670336 |