Dataset Information

Xenopus laevis alpha and beta thyroid hormone receptors.

ABSTRACT: The Xenopus laevis genome encodes two genes for the alpha (TR alpha) and two genes for the beta (TR beta) thyroid hormone receptors. The two TR alpha genes closely resemble their rat, human, and chicken counterparts. No alternatively spliced TR alpha cDNA clones were found in the 5' untranslated region (5' UTR). In contrast, complex alternative splicing of TR beta mRNA occurs within the 5' UTR as well as possible alternative transcriptional start sites. As many as eight exons encoding mainly the 5' UTR are alternatively spliced, giving rise to at least two amino termini for each of the two TR beta proteins. The 5' UTR of transcripts from both TR alpha and TR beta genes contain multiple AUG sequences with short open reading frames suggesting translational control mechanisms might play a role in expression of TR genes.

SUBMITTER: Yaoita Y

PROVIDER: S-EPMC54689 | biostudies-other | 1990 Sep

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Xenopus laevis alpha and beta thyroid hormone receptors.

Yaoita Y Y Shi Y B YB Brown D D DD

Proceedings of the National Academy of Sciences of the United States of America 19900901 18

The Xenopus laevis genome encodes two genes for the alpha (TR alpha) and two genes for the beta (TR beta) thyroid hormone receptors. The two TR alpha genes closely resemble their rat, human, and chicken counterparts. No alternatively spliced TR alpha cDNA clones were found in the 5' untranslated region (5' UTR). In contrast, complex alternative splicing of TR beta mRNA occurs within the 5' UTR as well as possible alternative transcriptional start sites. As many as eight exons encoding mainly the ...[more]

PMID: 2402492

Similar Datasets

Project description:INhibitor of Growth (ING) proteins belong to a large family of plant homeodomain finger-containing proteins important in epigenetic regulation and carcinogenesis. We have previously shown that ING1 and ING2 expression is regulated by thyroid hormone (TH) during metamorphosis of the Xenopus laevis tadpole. The present study investigates the possibility that ING proteins modulate TH action.Tadpoles expressing a Xenopus ING2 transgene (Trans(ING2)) were significantly smaller than tadpoles not expressing the transgene (Trans(GFP)). When exposed to 10 nM 3,5,3'-triiodothyronine (T(3)), premetamorphic Trans(ING2) tadpoles exhibited a greater reduction in tail, head, and brain areas, and a protrusion of the lower jaw than T(3)-treated Trans(GFP) tadpoles. Quantitative real time polymerase chain reaction (QPCR) demonstrated elevated TH receptor ? (TR?) and TH/bZIP transcript levels in Trans(ING2) tadpole tails compared to Trans(GFP) tadpoles while TR? mRNAs were unaffected. In contrast, no difference in TR?, TR? or insulin-like growth factor (IGF2) mRNA abundance was observed in the brain between Trans(ING2) and Trans(GFP) tadpoles. All of these transcripts, except for TR? mRNA in the brain, were inducible by the hormone in both tissues. Oocyte transcription assays indicated that ING proteins enhanced TR-dependent, T(3)-induced TR? gene promoter activity. Examination of endogenous T(3)-responsive promoters (TR? and TH/bZIP) in the tail by chromatin immunoprecipitation assays showed that ING proteins were recruited to TRE-containing regions in T(3)-dependent and independent ways, respectively. Moreover, ING and TR proteins coimmunoprecipitated from tail protein homogenates derived from metamorphic climax animals.We show for the first time that ING proteins modulate TH-dependent responses, thus revealing a novel role for ING proteins in hormone signaling. This has important implications for understanding hormone influenced disease states and suggests that the induction of ING proteins may facilitate TR function during metamorphosis in a tissue-specific manner.

Dataset Information

Xenopus laevis alpha and beta thyroid hormone receptors.

Publications

Xenopus laevis alpha and beta thyroid hormone receptors.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets