Corticosteroids are critical for development and for mediating stress responses across diverse vertebrate taxa. Study of frog metamorphosis has made significant breakthroughs in our understanding of corticosteroid signaling during development in non-mammalian vertebrate species. However, lack of adequate corticosterone (CORT) response genes in tadpoles make identification and quantification of CORT responses challenging. Here, we characterized a CORT-response gene
- Award ID(s):
- 2035732
- NSF-PAR ID:
- 10385255
- Date Published:
- Journal Name:
- Endocrinology
- Volume:
- 164
- Issue:
- 1
- ISSN:
- 1945-7170
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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frzb (frizzled related protein) previously identified inXenopus tropicalis tadpole tail skin by an RNA-seq study. We validated the RNA-seq results that CORT and not thyroid hormone inducesfrzb in the tails using quantitative PCR. Further, maximumfrzb expression was achieved by 100-250 nM CORT within 12-24 hours.frzb is not significantly induced in the liver and brain in response to 100 nM CORT. We also found no change infrzb expression across natural metamorphosis when endogenous CORT levels peak. Surprisingly,frzb is only induced by CORT inX. tropicalis tails and not inXenopus laevis tails. The exact downstream function of increasedfrzb expression in tails in response to CORT is not known, but the specificity of hormone response and its high mRNA expression levels in the tail renderfrzb a useful marker of exogenous CORT-response independent of thyroid hormone for exogenous hormone treatments andin-vivo endocrine disruption studies. -
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