Ursus americanus
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ABSTRACT:
PROVIDER: PRJNA263797 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P < 0.01 and fold change > 0.5) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment analysis showed an elevated proportion in hibernating bears of over-expressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development and bone biosynthesis. Apoptosis genes demonstrated a tendency for down regulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, c- Fos) were significantly under expressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation. Black bears sampled during winter hibernation were compared with the animals sampled during summer. Bone RNA were hybridized on a custom 12,800 cDNA probe nylon membrane microarray platform . Six hibernating and six summer active bears were studied in this experiments.
2012-02-15 | E-GEOD-35796 | biostudies-arrayexpress
Project description:Physical inactivity reduces mechanical load on the skeleton, which leads to losses of bone mass and strength in non hibernating mammalian species. Although bears are largely inactive during hibernation, they show no loss in bone mass and strength. To obtain insight into molecular mechanisms preventing disuse bone loss, we conducted a large-scale screen of transcriptional changes in trabecular bone comparing winter hibernating and summer non hibernating black bears using a custom 12,800 probe cDNA microarray. A total of 241 genes were differentially expressed (P < 0.01 and fold change > 0.5) in the ilium bone of bears between winter and summer. The Gene Ontology and Gene Set Enrichment analysis showed an elevated proportion in hibernating bears of over-expressed genes in six functional sets of genes involved in anabolic processes of tissue morphogenesis and development including skeletal development, cartilage development and bone biosynthesis. Apoptosis genes demonstrated a tendency for down regulation during hibernation. No coordinated directional changes were detected for genes involved in bone resorption, although some genes responsible for osteoclast formation and differentiation (Ostf1, Rab9a, c- Fos) were significantly under expressed in bone of hibernating bears. Elevated expression of multiple anabolic genes without induction of bone resorption genes, and the down regulation of apoptosis related genes, likely contribute to the adaptive mechanism that preserves bone mass and structure through prolonged periods of immobility during hibernation.
2012-02-15 | GSE35796 | GEO
Project description:Hibernation is energy saving adaptation involving suppression of activity to survive in highly seasonal environments. Immobility and disuse generate muscle loss in most mammalian species. In contrast to other mammals, bears and ground squirrels demonstrate limited muscle atrophy over the physical inactivity of winter hibernation. This suggests that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional program underlying molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screening in hind limb muscles comparing hibernating and summer active black bears and arctic ground squirrels by the use of custom 9,600 probe cDNA microarrays. The molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during hibernation that implies induction of translation at different hibernation states. The induction of protein biosynthesis likely contributes to attenuation of disuse muscle atrophy through prolonged periods of immobility and starvation. This adaptive mechanism allows hibernating mammals to maintain full musculoskeletal function and preserve mobility during and immediately after hibernation, thus promoting survival. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction of multiply genes involved in oxidation reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation. Black bears sampled during winter hibernation were compared with the animals sampled during summer. Muscle tissue were hybridized on a custom 12,800 cDNA probe nylon membrane microarray platform . Six hibernating and six summer active bears were studied in the experiment.
2014-10-16 | E-GEOD-62220 | biostudies-arrayexpress
Project description:We analyzed gene expression in the American black bear, Ursus americanus, using a custom 12,800 cDNA probe (BA02) microarray to detect differences in expression that occur in heart and liver during winter hibernation in comparison to summer active animals. We identified 245 genes in heart and 319 genes in liver that were differentially expressed between winter and summer. The expression of 24 genes was significantly elevated during hibernation in both heart and liver. These genes are mostly involved in lipid catabolism and protein biosynthesis and include RNA binding protein motif 3 (Rbm3), which enhances protein synthesis at mildly hypothermic temperatures. Elevated expression of protein biosynthesis genes suggests induction of translation that may be related to adaptive mechanisms reducing cardiac and muscle atrophies over extended periods of low metabolism and immobility during hibernation in bears. Coordinated reduction of transcription of genes involved in amino acid catabolism suggests redirection of amino acids from catabolic pathways to protein biosynthesis. We identify common for black bears and small mammalian hibernators transcriptional changes in the liver that include induction of genes responsible for fatty acid β oxidation and carbohydrate synthesis and depression of genes involved in lipid biosynthesis, carbohydrate catabolism, cellular respiration and detoxification pathways. Our findings show that modulation of gene expression during winter hibernation represents molecular mechanism of adaptation to extreme environments. Black bears sampled during winter hibernation were compared with the animals sampled during summer. Two tissue types, liver and heart, were hybridized on a custom 12,800 cDNA probe nylon membrane microarray platform . Six hibernating and five summer active bears were studied in experiments with liver tissue, six hibernating and five summer active animals were tested with heart tissue.
2011-05-10 | E-GEOD-27875 | biostudies-arrayexpress
Project description:Gene Expression Data of Hibernating and Summer Active Black Bears
| PRJNA114885 | ENA
Project description:Hibernation is energy saving adaptation involving suppression of activity to survive in highly seasonal environments. Immobility and disuse generate muscle loss in most mammalian species. In contrast to other mammals, bears and ground squirrels demonstrate limited muscle atrophy over the physical inactivity of winter hibernation. This suggests that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional program underlying molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screening in hind limb muscles comparing hibernating and summer active black bears and arctic ground squirrels by the use of custom 9,600 probe cDNA microarrays. The molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during hibernation that implies induction of translation at different hibernation states. The induction of protein biosynthesis likely contributes to attenuation of disuse muscle atrophy through prolonged periods of immobility and starvation. This adaptive mechanism allows hibernating mammals to maintain full musculoskeletal function and preserve mobility during and immediately after hibernation, thus promoting survival. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction of multiply genes involved in oxidation reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation. Arctic ground squirrels sampled during winter hibernation were compared with the animals sampled during summer. Muscle was hybridized on a custom 9,600 probes nylon membrane microarray platform. Ten in late torpor, four in early arousal, then in late arousal were studied in experiments.
2014-10-16 | E-GEOD-62377 | biostudies-arrayexpress
Project description:Modulation of gene expression in heart and liver of hibernating black bears (Ursus americanus)
| PRJNA138223 | ENA
Project description:Hibernation is energy saving adaptation involving suppression of activity to survive in highly seasonal environments. Immobility and disuse generate muscle loss in most mammalian species. In contrast to other mammals, bears and ground squirrels demonstrate limited muscle atrophy over the physical inactivity of winter hibernation. This suggests that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional program underlying molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screening in hind limb muscles comparing hibernating and summer active black bears and arctic ground squirrels by the use of custom 9,600 probe cDNA microarrays. The molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during hibernation that implies induction of translation at different hibernation states. The induction of protein biosynthesis likely contributes to attenuation of disuse muscle atrophy through prolonged periods of immobility and starvation. This adaptive mechanism allows hibernating mammals to maintain full musculoskeletal function and preserve mobility during and immediately after hibernation, thus promoting survival. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction of multiply genes involved in oxidation reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation.
2014-10-16 | GSE62220 | GEO
Project description:Hibernation is energy saving adaptation involving suppression of activity to survive in highly seasonal environments. Immobility and disuse generate muscle loss in most mammalian species. In contrast to other mammals, bears and ground squirrels demonstrate limited muscle atrophy over the physical inactivity of winter hibernation. This suggests that hibernating mammals have adaptive mechanisms to prevent disuse muscle atrophy. To identify common transcriptional program underlying molecular mechanisms preventing muscle loss, we conducted a large-scale gene expression screening in hind limb muscles comparing hibernating and summer active black bears and arctic ground squirrels by the use of custom 9,600 probe cDNA microarrays. The molecular pathway analysis showed an elevated proportion of overexpressed genes involved in all stages of protein biosynthesis and ribosome biogenesis in muscle of both species during hibernation that implies induction of translation at different hibernation states. The induction of protein biosynthesis likely contributes to attenuation of disuse muscle atrophy through prolonged periods of immobility and starvation. This adaptive mechanism allows hibernating mammals to maintain full musculoskeletal function and preserve mobility during and immediately after hibernation, thus promoting survival. The lack of directional changes in genes of protein catabolic pathways does not support the importance of metabolic suppression for preserving muscle mass during winter. Coordinated reduction of multiply genes involved in oxidation reduction and glucose metabolism detected in both species is consistent with metabolic suppression and lower energy demand in skeletal muscle during inactivity of hibernation.
2014-10-16 | GSE62377 | GEO
Project description:Preservation of bone mass and structure in hibernating black bears (Ursus americanus) through elevated expression of anabolic genes
| PRJNA152193 | ENA