Gene Expression data of Arctic Ground Squirrel during the multiple stages of hibernation
Ontology highlight
ABSTRACT:
ORGANISM(S): Callospermophilus lateralis Ictidomys tridecemlineatus Urocitellus parryii
PROVIDER: GSE5414 | GEO | 2006/08/03
SECONDARY ACCESSION(S): PRJNA96231
REPOSITORIES: GEO
Similar Datasets
Project description:Differential gene expression in a wide range of tissues including brown adipose tissue (BAT), liver, heart, hypothalamus, and skeletal muscle in hibernating arctic ground squirrels during multiple stages in torpor-arousal cycles compared to non-hibernating (post-reproductive) animals with illumina beadarray technology. Arctic Ground Squirrels were sampled at four stages of hibernation: early arousal denoted as EA (1-2 hrs after Tb cross 30¡C, n=4), late arousal denoted as LA (7-8 hrs after Tb cross 30¡C, n=4), early torpor denoted as ET (10-20% of torpid episode, n=4) and late torpor denoted as LT (80-90% of torpid episode, n=5), where Tb is the body temperature and the length of torpid episode is estimated from the previous torpor bout. Post-reproductive animals denoted as PR (n=7) were used as non-hibernating control. Five tissue types: brown adipose tissue (BAT), liver, heart, hypothalamus, and skeletal muscle were hybridized on two customized 700-gene beadarray platforms: 1A and 2A on 96-sample Illumina ArrayMatrix. The data of a pilot study involving brown adipose tissue (BAT), liver, and skeletal muscle on 16-sample Illumina BeadChip denoted as 16chip are also included in this series.
2010-07-01 | E-GEOD-5414 | biostudies-arrayexpress
Project description:Mammalian hibernators display phenotypes similar to physiological conditions in non-hibernating species under conditions of calorie restriction and fasting, hypoxia, hypothermia, ischemia-reperfusion, and sleep. However, whether or how similarities are also reflected on molecular and genetic levels is unclear. We identified molecular signatures of torpor and arousal in hibernation using a new custom-designed cDNA microarray for the arctic ground squirrel (Urocitellus parryii,) and compared them to molecular signatures of selected phenotypes in mouse. Our results show that differential gene expression related to metabolism during torpor is closely related to that during calorie restriction and hypoxia. PPARM-NM-1 is crucial for metabolic remodeling in hibernation. Genes related to the sleep-wake cycle and temperature response genes induced by hypothermia follow the same expression changes as in torpor-arousal cycle. Increased fatty acid metabolism might contribute to the protection against ischemia-reperfusion injury during hibernation. Further, by comparing with thousands of pharmacological signatures, we identified drugs that may induce similar expression patterns in human cell lines as during hibernation. Arctic ground squirrels sampled during winter hibernation were compared with the animals sampled during summer. Liver was hybridized on a custom 9,600 probes nylon membrane microarray platform. Four squirrels in early torpor, five in late torpor, four in early arousal, four in late arousal, and seven in summer active were studied in experiments.
2012-09-01 | E-GEOD-38700 | biostudies-arrayexpress
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:Hibernation is an energy-saving strategy adopted by a wide range of mammals to survive highly seasonal or unpredictable environments. Arctic ground squirrels living in Alaska provide an extreme example, with 6-9 months long hibernation seasons when body temperature alternates between levels near 0 C during torpor and 37 C during arousal episodes. Heat production during hibernation is provided, in part, by non-shivering thermogenesis that occurs in large deposits of brown adipose tissue (BAT). BAT is active at tissue temperatures from 0 to 37 C during rewarming and continuously at near 0 C during torpor in subfreezing conditions. Despite its crucial role in hibernation, the global gene expression patterns in BAT during hibernation compared to the non-hibernation season remain largely unknown. We report a large-scale study of differential gene expression in BAT between winter hibernating and summer active arctic ground squirrels using mouse microarrays. Selected differentially expressed genes identified on the arrays were validated by quantitative real-time PCR using ground squirrel specific primers. Our results show that the mRNA levels of the genes involved in nearly every step of the biochemical pathway leading to non-shivering thermogenesis are significantly increased in BAT during hibernation, whereas those of genes involved in protein biosynthesis are significantly decreased compared to the summer active animals in August. The differentially expressed genes also include those involved in adipose differentiation, substrate transport, and structure remodeling, which may enhance thermogenesis at low tissue temperatures in BAT. Keywords: hibernating animals vs. summer active animals
2005-10-21 | GSE3426 | GEO
Project description:Thirteen-lined ground squirrels (Ictidomys tridecemlineatus) hibernate for several months each winter without access to water, but the mechanisms that maintain fluid homeostasis during hibernation are poorly understood. In torpor, when body temperature (TB) reaches 4°C, squirrels decrease metabolism, slow heart rate, and reduce plasma levels of the antidiuretic hormones arginine vasopressin (AVP) and oxytocin (OXT). Squirrels spontaneously undergo interbout arousal (IBA) every 2 weeks, temporarily recovering an active-like metabolism and a TB of 37°C for up to 48 h. Despite the low levels of AVP and OXT during torpor, profound increases in blood pressure and heart rate during the torpor-IBA transition are not associated with massive fluid loss, suggesting the existence of a mechanism that protects against diuresis at a low TB. Here, we demonstrate that the antidiuretic hormone release pathway is activated by hypothalamic supraoptic nucleus (SON) neurons early in the torpor-arousal transition. SON neuron activity, dense-core vesicle release from the posterior pituitary, and plasma hormone levels all begin to increase before TB reaches 10°C. In vivo fiber photometry of SON neurons from hibernating squirrels, together with RNA sequencing and c-FOS immunohistochemistry, confirms that SON is electrically, transcriptionally, and translationally active to monitor blood osmolality throughout the dynamic torpor-arousal transition. Our work emphasizes the importance of the antidiuretic pathway during the torpor-arousal transition and reveals that the neurophysiological mechanism that coordinates the hormonal response to retain fluid is active at an extremely low TB, which is prohibitive for these processes in non-hibernators.
2024-02-05 | GSE231418 | GEO
Project description:Metatranscriptomes of hibernating arctic ground squirrels fed a 9% or 18% protein pre-hibernationdiet
| PRJEB64009 | ENA
Project description:Metatranscriptomes of hibernating arctic ground squirrels fed a 9% or 18% protein pre-hibernationdiet
| PRJEB64010 | ENA
Project description:Mammalian hibernation is characterized by metabolic rate depression and a strong decrease in core body temperature that together create energy savings such that most species do not have to eat over the winter months. Brown adipose tissue (BAT), a thermogenic tissue that uses uncoupled mitochondrial respiration to generate heat instead of ATP, plays a major role in rewarming from deep torpor. The present study used label-free phosphoproteomics to investigate changes in BAT from thirteen-lined ground squirrels (Ictidomys tridecemlineatus), comparing euthermic squirrels with squirrels in deep torpor. Differential expression of mitochondrial proteins was also investigated. Surprisingly, mitochondrial membrane and matrix protein expression in BAT was largely constant between active euthermic squirrels and their hibernating counterparts. Validation by immunoblotting confirmed that the protein levels of mitochondrial respiratory chain complexes were largely unchanged. However, phosphoproteomics showed that pyruvate dehydrogenase (PDH) phosphorylation increased during ground squirrel hibernation, and this was confirmed by immunoblotting with phospho-specific antibodies. PDH phosphorylation leads to its inactivation, which suggests that BAT carbohydrate oxidation is inhibited during hibernation. Phosphorylation of hormone-sensitive lipase (HSL) also increased during hibernation, suggesting that HSL would be in a partly activated state in BAT to produce the fatty acids that are likely the primary fuel for thermogenesis during arousal.
2017-07-11 | PXD004261 | Pride
Project description:Mammalian hibernators display phenotypes similar to physiological conditions in non-hibernating species under conditions of calorie restriction and fasting, hypoxia, hypothermia, ischemia-reperfusion, and sleep. However, whether or how similarities are also reflected on molecular and genetic levels is unclear. We identified molecular signatures of torpor and arousal in hibernation using a new custom-designed cDNA microarray for the arctic ground squirrel (Urocitellus parryii,) and compared them to molecular signatures of selected phenotypes in mouse. Our results show that differential gene expression related to metabolism during torpor is closely related to that during calorie restriction and hypoxia. PPARα is crucial for metabolic remodeling in hibernation. Genes related to the sleep-wake cycle and temperature response genes induced by hypothermia follow the same expression changes as in torpor-arousal cycle. Increased fatty acid metabolism might contribute to the protection against ischemia-reperfusion injury during hibernation. Further, by comparing with thousands of pharmacological signatures, we identified drugs that may induce similar expression patterns in human cell lines as during hibernation.
2012-09-01 | GSE38700 | GEO
Project description:This series represents the heart transcriptome for animals sampled during summer, interbout arousal, and late torpor Keywords = squirrel, heart, hibernation Keywords: other
2004-12-03 | GSE2023 | GEO