Dataset Information

Hypoxia-induced reprogramming of the cardiac phenotype in American alligators (Alligator mississippiensis) revealed by quantitative proteomics

ABSTRACT: Hypoxic exposure during development can have a profound influence on offspring physiology, including cardiac dysfunction, yet many reptile embryos naturally experience periods of hypoxia in buried nests. American alligators experimentally exposed to developmental hypoxia demonstrate morphological and functional changes to the heart that persist into later life stages; however, the molecular bases of these changes remain unknown. We tested if targeted and persistent changes in steady-state protein expression underlie this hypoxic heart phenotype, using isobaric tags for relative and absolute quantitation (iTRAQ) proteomics. Alligator eggs were reared under normoxia or 10% hypoxia, then either sampled (embryo) or returned to normoxia for 2 years (juvenile). Three salient findings emerge from the integrated analysis of the 145 differentially expressed proteins in hypoxia-reared animals: (1) significant protein-protein interaction networks were identified only in up-regulated, indicating that the effects of developmental hypoxia are stimulatory and directed; (2) the up-regulated proteins substantially enriched processes related to protein turnover, cellular organization, and metabolic pathways, supporting increased resource allocation towards building and maintaining a higher functioning heart; and (3) the juvenile cardiac proteome retained many of the signature changes observed in embryonic hearts, supporting long-term reprogramming of cardiac myocytes induced by hypoxia during critical periods of development.

INSTRUMENT(S): QE-HF-X

ORGANISM(S): Alligator Mississippiensis (ncbitaxon:8496)

SUBMITTER: Sarah Alderman

PROVIDER: MSV000083838 | MassIVE | Wed May 22 10:01:00 BST 2019

SECONDARY ACCESSION(S): PXD013974

REPOSITORIES: MassIVE

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Publications

Growing up gator: a proteomic perspective on cardiac maturation in an oviparous reptile, the American alligator (Alligator mississippiensis).

Alderman Sarah L SL Crossley Dane A DA Elsey Ruth M RM Gillis Todd E TE

Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology 20200122 2

We recently described lasting changes in the cardiac proteome of American alligators (Alligator mississippiensis) reared under hypoxic conditions, that resemble what embryos encounter in natural nests. While these changes were consistent with functional differences in cardiac performance induced by developmental hypoxia, the magnitude of this response was dwarfed by a much greater effect of development alone (76% of the total differentially abundant proteins). This means that substantial differe ...[more]

PMID: 31970485

Publication: 1/2

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