title: Expression profiles of novel thyroid hormone-responsive genes and proteins in the tail of Xenopus laevis tadpoles undergoing precocious metamorphosis.
abstract: Thyroid hormones (THs) are critical for the growth, development, and homeostasis of many organisms and are necessary for metamorphosis of Xenopus laevis tadpoles. TH-induced metamorphosis requires alterations in the transcriptome and the proteome. However, only a few of the molecular components of this developmental program have been identified and their interrelationship remains unclear. Using a cDNA array comprised of 420 known anuran genes and quantitative PCR, we have identified 93 TH-responsive genes in the tail of premetamorphic tadpoles after exogenous administration of T3. Fifty-three of these mRNA transcripts have not previously been characterized as TH responsive in any species. The gene expression profiles show distinctive temporal patterns with most transcript steady-state levels increasing after induction of metamorphosis. Two-dimensional gel electrophoresis of total protein extracts from the tail shows changes in steady-state levels of many proteins after T3 treatment. Of the up-regulated proteins, 10 were identified by peptide mass mapping. These data identify potential components involved in the regulation of Xenopus tail regression by T3 and begin to address a critical question regarding the interrelationship between the transcriptome and the proteome in TH-dependent developmental processes.
authors.affiliation: Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada V8W 3P6. chelbing@uvic.ca
authors.forename: Caren C
authors.initials: CC
authors.lastname: Helbing
authors.forename: Kate
authors.initials: K
authors.lastname: Werry
authors.forename: Doug
authors.initials: D
authors.lastname: Crump
authors.forename: Dominik
authors.initials: D
authors.lastname: Domanski
authors.forename: Nik
authors.initials: N
authors.lastname: Veldhoen
authors.forename: Carmen M
authors.initials: CM
authors.lastname: Bailey
mesh_terms: D000818:Animals; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D007814:Larva; D008668:Metallothionein / Q000187:drug effects / Q000235:genetics; D008675:Metamorphosis, Biological / Q000235:genetics*; D005810:Multigene Family; D020411:Oligonucleotide Array Sequence Analysis; D011988:Receptors, Thyroid Hormone / Q000187:drug effects / Q000235:genetics; D013623:Tail; D013963:Thyroid Hormones / Q000494:pharmacology* / Q000502:physiology; D014284:Triiodothyronine / Q000494:pharmacology; D014982:Xenopus laevis / Q000235:genetics* / Q000254:growth & development
chemical_list: D011988:Receptors, Thyroid Hormone; D013963:Thyroid Hormones; D014284:Triiodothyronine; D008668:Metallothionein