Transformation of metabolism with age and lifestyle in Antarctic seals: a case study of systems biology approach to cross-species microarray experiment

Colorado State University Department of Biology, Fort Collins, CO 80523, USA.
BMC Systems Biology (Impact Factor: 2.44). 09/2010; 4(1):133. DOI: 10.1186/1752-0509-4-133
Source: PubMed


The metabolic transformation that changes Weddell seal pups born on land into aquatic animals is not only interesting for the study of general biology, but it also provides a model for the acquired and congenital muscle disorders which are associated with oxygen metabolism in skeletal muscle. However, the analysis of gene expression in seals is hampered by the lack of specific microarrays and the very limited annotation of known Weddell seal (Leptonychotes weddellii) genes.
Muscle samples from newborn, juvenile, and adult Weddell seals were collected during an Antarctic expedition. Extracted RNA was hybridized on Affymetrix Human Expression chips. Preliminary studies showed a detectable signal from at least 7000 probe sets present in all samples and replicates. Relative expression levels for these genes was used for further analysis of the biological pathways implicated in the metabolism transformation which occurs in the transition from newborn, to juvenile, to adult seals. Cytoskeletal remodeling, WNT signaling, FAK signaling, hypoxia-induced HIF1 activation, and insulin regulation were identified as being among the most important biological pathways involved in transformation.
In spite of certain losses in specificity and sensitivity, the cross-species application of gene expression microarrays is capable of solving challenging puzzles in biology. A Systems Biology approach based on gene interaction patterns can compensate adequately for the lack of species-specific genomics information.

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Available from: Andrey Ptitsyn,
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    • "In terms of skeletal muscle development, the cessation of weaning and commencement of diving in Weddell seals induces developmental changes in muscle physiology that parallel changes in activity. Preliminary microarray results indicate differential expression of RNA transcripts associated with various ontogenic signaling pathways, in addition to differences in transcripts associated with lipid metabolism, among age classes (Kanatous et al., 2008b; Ptitsyn et al., 2010). These previous findings mirrored results describing significant changes in the lipid composition and potential utilization of fatty acids in skeletal muscle during these developmental stages (Trumble et al., 2010). "
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