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The hibernating South American marsupial, Dromiciops gliroides, displays torpor-sensitive microRNA expression patterns.

Hadj-Moussa H, Moggridge JA, Luu BE, Quintero-Galvis JF, Gaitán-Espitia JD, Nespolo RF, Storey KB - Sci Rep (2016)

Bottom Line: Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor.In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms.These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.

ABSTRACT
When faced with adverse environmental conditions, the marsupial Dromiciops gliroides uses either daily or seasonal torpor to support survival and is the only known hibernating mammal in South America. As the sole living representative of the ancient Order Microbiotheria, this species can provide crucial information about the evolutionary origins and biochemical mechanisms of hibernation. Hibernation is a complex energy-saving strategy that involves changes in gene expression that are elicited in part by microRNAs. To better elucidate the role of microRNAs in orchestrating hypometabolism, a modified stem-loop technique and quantitative PCR were used to characterize the relative expression levels of 85 microRNAs in liver and skeletal muscle of control and torpid D. gliroides. Thirty-nine microRNAs were differentially regulated during torpor; of these, 35 were downregulated in liver and 11 were differentially expressed in skeletal muscle. Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor. In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms. These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy.

No MeSH data available.


Related in: MedlinePlus

DIANA mirPath analysis of eleven miRNAs showing torpor-specific expression in D. gliroides skeletal muscle predicted that twelve genes involved in mTOR signalling are targeted by eight miRNAs from this group. Predicted target genes (grey boxes) and their putative miRNA regulators (green bars indicate increased miRNA expression and red bars indicate decreased miRNA expression during torpor) are shown in the context of a simplified Akt/mTOR signalling pathway. Genes in white boxes were not predicted targets of the eleven differentially expressed miRNAs in skeletal muscle.
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f3: DIANA mirPath analysis of eleven miRNAs showing torpor-specific expression in D. gliroides skeletal muscle predicted that twelve genes involved in mTOR signalling are targeted by eight miRNAs from this group. Predicted target genes (grey boxes) and their putative miRNA regulators (green bars indicate increased miRNA expression and red bars indicate decreased miRNA expression during torpor) are shown in the context of a simplified Akt/mTOR signalling pathway. Genes in white boxes were not predicted targets of the eleven differentially expressed miRNAs in skeletal muscle.

Mentions: MicroRNAs with altered expression during torpor in D. gliroides liver and skeletal muscle were subjected to bioinformatic target enrichment analyses using DIANA mirPath v2.0. This program identifies the potential KEGG pathways that are collectively targeted by the query miRNAs. DIANA mirPath indicated that decreased expression of miRNAs in liver of torpid animals were most closely associated with three signalling pathways [1] MAPK signalling (p = 8.09E−25), with 96 genes thought to be targeted by 32 of the 35 down-regulated miRNAs; [2] mTOR signalling (p = 3.09E−20), with 32 genes targeted by 23 of 35 torpor-sensitive miRNAs (Fig. 2); and [3] PI3K/Akt signalling (p = 7.44E−07), with 110 genes targeted by 33 of 35 differentially expressed miRNAs (Table 1, Fig. 2). In skeletal muscle, eleven torpor-associated miRNAs were linked to pathways of [1] focal adhesion (p = 7.44E−07), with 29 genes targeted by seven miRNAs; [2] ErbB signalling (p = 9.60E−06), with sixteen genes targeted by seven miRNAs; and [3] mTOR signalling (p = 1.64E−05), involving twelve genes and eight miRNAs (Table 1 and Fig. 3).


The hibernating South American marsupial, Dromiciops gliroides, displays torpor-sensitive microRNA expression patterns.

Hadj-Moussa H, Moggridge JA, Luu BE, Quintero-Galvis JF, Gaitán-Espitia JD, Nespolo RF, Storey KB - Sci Rep (2016)

DIANA mirPath analysis of eleven miRNAs showing torpor-specific expression in D. gliroides skeletal muscle predicted that twelve genes involved in mTOR signalling are targeted by eight miRNAs from this group. Predicted target genes (grey boxes) and their putative miRNA regulators (green bars indicate increased miRNA expression and red bars indicate decreased miRNA expression during torpor) are shown in the context of a simplified Akt/mTOR signalling pathway. Genes in white boxes were not predicted targets of the eleven differentially expressed miRNAs in skeletal muscle.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4835794&req=5

f3: DIANA mirPath analysis of eleven miRNAs showing torpor-specific expression in D. gliroides skeletal muscle predicted that twelve genes involved in mTOR signalling are targeted by eight miRNAs from this group. Predicted target genes (grey boxes) and their putative miRNA regulators (green bars indicate increased miRNA expression and red bars indicate decreased miRNA expression during torpor) are shown in the context of a simplified Akt/mTOR signalling pathway. Genes in white boxes were not predicted targets of the eleven differentially expressed miRNAs in skeletal muscle.
Mentions: MicroRNAs with altered expression during torpor in D. gliroides liver and skeletal muscle were subjected to bioinformatic target enrichment analyses using DIANA mirPath v2.0. This program identifies the potential KEGG pathways that are collectively targeted by the query miRNAs. DIANA mirPath indicated that decreased expression of miRNAs in liver of torpid animals were most closely associated with three signalling pathways [1] MAPK signalling (p = 8.09E−25), with 96 genes thought to be targeted by 32 of the 35 down-regulated miRNAs; [2] mTOR signalling (p = 3.09E−20), with 32 genes targeted by 23 of 35 torpor-sensitive miRNAs (Fig. 2); and [3] PI3K/Akt signalling (p = 7.44E−07), with 110 genes targeted by 33 of 35 differentially expressed miRNAs (Table 1, Fig. 2). In skeletal muscle, eleven torpor-associated miRNAs were linked to pathways of [1] focal adhesion (p = 7.44E−07), with 29 genes targeted by seven miRNAs; [2] ErbB signalling (p = 9.60E−06), with sixteen genes targeted by seven miRNAs; and [3] mTOR signalling (p = 1.64E−05), involving twelve genes and eight miRNAs (Table 1 and Fig. 3).

Bottom Line: Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor.In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms.These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy.

View Article: PubMed Central - PubMed

Affiliation: Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.

ABSTRACT
When faced with adverse environmental conditions, the marsupial Dromiciops gliroides uses either daily or seasonal torpor to support survival and is the only known hibernating mammal in South America. As the sole living representative of the ancient Order Microbiotheria, this species can provide crucial information about the evolutionary origins and biochemical mechanisms of hibernation. Hibernation is a complex energy-saving strategy that involves changes in gene expression that are elicited in part by microRNAs. To better elucidate the role of microRNAs in orchestrating hypometabolism, a modified stem-loop technique and quantitative PCR were used to characterize the relative expression levels of 85 microRNAs in liver and skeletal muscle of control and torpid D. gliroides. Thirty-nine microRNAs were differentially regulated during torpor; of these, 35 were downregulated in liver and 11 were differentially expressed in skeletal muscle. Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor. In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms. These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy.

No MeSH data available.


Related in: MedlinePlus