Project description:The serum hormone levels including T3 and T4 were dramatically decreased in Glis3-null mice due to reduced production of thyroid hormones in thyroid. Gene expression profile and EdU incorporation analysis between WT and Glis3-null mice showed that the cell proliferation was greatly reduced in Glis3-null thyroid. Goitergenic diet (low iodine diet; LID) dramatically enhanced serum TSH levels in both WT and Glis3-null mice, however thyroid goiter was observed in WT mice but not in Glis3-null mice. A subset of genes associated with thyroid hormone production including Pendrin (Slc26a4), Nis (Na+/I– symporter, Slc5a5), Duoxa2 (dualoxidase A2), Tpo (thyroperoxidase), and Dio1 (Deiodinase1) was significantly induced in WT but not in Glis3-null mice by LID feeding.
Project description:Deficiency in Krüppel-like zinc finger transcription factor, GLI-Similar 3 (GLIS3) in humans is associated with the development of congenital hypothyroidism. However, the functions of GLIS3 in the thyroid gland and by what mechanism GLIS3-dysfunction causes hypothyroidism are unknown. In this study, we demonstrate that GLIS3 acts downstream of thyroid stimulating hormone (TSH)/TSHR and is indispensable for TSH/TSHR-mediated induction of thyroid follicular cell proliferation and thyroid hormone biosynthesis. ChIP-Seq and promoter analysis revealed that GLIS3 is critical for the transcriptional activation of several genes required for thyroid hormone biosynthesis, including the iodide transporters Nis and Pds, indicating that these genes are directly regulated by GLIS3. The repression of cell proliferation regulatory genes is due to the inhibition of TSH-mediated activation of the mTORC1/RPS6 pathway as well as direct transcriptional regulation of several cell division-related genes by GLIS3. Consequently, GLIS3-deficiency prevents the development of goiter as well as the induction of inflammatory and fibrotic genes during chronic elevation of circulating TSH. Our study identifies GLIS3 as a new and key regulator of TSH/TSHR-mediated thyroid hormone biosynthesis and proliferation of thyroid follicular cells, and uncovers a mechanism by which GLIS3-deficiency causes congenital hypothyroidism and prevents goiter development.
Project description:Comparison of cistromes from PAX8, NKX2.1, and FOXE1 ChIP-Seq analysis using mouse thyroid gland and rat thyrocyte PCCl3 cells revealed that there is a significant overlap between GLIS3 binding regions and those of PAX8, NKX2.1, and FOXE1 in genes associated with thyroid hormone biosynthesis.
Project description:The importance of unanchored Ub in innate immunity has been shown only for a limited number of unanchored Ub-interactors. We investigated what additional cellular factors interact with unanchored Ub and whether unanchored Ub plays a broader role in innate immunity. To identify unanchored Ub-interacting factors from murine lungs, we used His-tagged recombinant poly-Ub chains as bait. These chains were mixed with lung tissue lysates and protein complexes were isolated with Ni-NTA beads. Sample elutions were subjected to mass spectrometry (LC-MSMS) analysis.
