Endocrinology Journal Article

Thrb Enhancer Mutations

March 14, 2023
 

Hong Liu, Ailing Lu, Kevin A Kelley, Douglas Forrest
Endocrinology, Volume 164, Issue 3, March 2023, bqad006
https://doi.org/10.1210/endocr/bqad006

Abstract

The function of a hormone receptor requires mechanisms to control precisely where, when, and at what level the receptor gene is expressed. An intriguing case concerns the selective induction of thyroid hormone receptor β2 (TRβ2), encoded by Thrb, in the pituitary and also in cone photoreceptors, in which it critically regulates expression of the opsin photopigments that mediate color vision. Here, we investigate the physiological significance of a candidate enhancer for induction of TRβ2 by mutagenesis of a conserved intron region in its natural context in the endogenous Thrb gene in mice. Mutation of e-box sites for bHLH (basic-helix-loop-helix) transcription factors preferentially impairs TRβ2 expression in cones whereas mutation of nearby sequences preferentially impairs expression in pituitary. A deletion encompassing all sites impairs expression in both tissues, indicating bifunctional activity. In cones, the e-box mutations disrupt chromatin acetylation, blunt the developmental induction of TRβ2, and ultimately impair cone opsin expression and sensitivity to longer wavelengths of light. These results demonstrate the necessity of studying an enhancer in its natural chromosomal context for defining biological relevance and reveal surprisingly critical nuances of level and timing of enhancer function. Our findings illustrate the influence of noncoding sequences over thyroid hormone functions.

Read the article

 

You may also like...

Publishing Benefits

Author Resource Center

We provide our journal authors with a variety of resources for increasing the discoverability and citation of their published work. Use these tools and tips to broaden the impact of your article.
Publishing Benefits

Author Resource Center

We provide our journal authors with a variety of resources for increasing the discoverability and citation of their published work. Use these tools and tips to broaden the impact of your article.

Thematic Issue

Latest Thematic Issue

immuno-endocrinology
Read our special collections of Endocrine Society journal articles, curated by topic, Altmetric Attention Scores, and Featured Article designations.

Read our special collections of Endocrine Society journal articles, curated by topic, Altmetric Attention Scores, and Featured Article designations.

Back to top

Who We Are

For 100 years, the Endocrine Society has been at the forefront of hormone science and public health. Read about our history and how we continue to serve the endocrine community.