Related Experiment Video
Updated: Oct 19, 2025
08:33
An Ex vivo Culture System to Study Thyroid Development
Published on: June 6, 2014
11.8K
Primary Cilia Mediate TSH-Regulated Thyroglobulin Endocytic Pathways.
Junguee Lee1, Hae Joung Sul1, Kun-Ho Kim2
1Department of Pathology, Daejeon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
Frontiers in Endocrinology
|September 23, 2021
Summary
Primary cilia are essential for thyroid function, regulating thyroglobulin (Tg) uptake via LRP2/megalin. Impaired cilia reduce Tg levels, highlighting cilia
Area of Science:
- Cell Biology
- Endocrinology
- Molecular Biology
Background:
- Primary cilia act as sensory organelles involved in cellular signaling.
- Thyroglobulin (Tg) exocytosis and endocytosis are vital for thyroid follicular cell function.
- LRP2/megalin is a receptor mediating Tg endocytosis in thyrocytes.
Purpose of the Study:
- To investigate the role of primary cilia in regulating LRP2/megalin expression and thyroglobulin (Tg) endocytosis in the thyroid gland.
- To determine the impact of ciliogenesis on LRP2/megalin localization and function in response to TSH stimulation.
Main Methods:
- Utilized MMI-treated mice to induce hyperthyroidism and ciliogenesis.
- Employed Tg-Cre;Ift88 mice to study the effects of defective primary cilia.
- Assessed LRP2/megalin expression, localization, and serum Tg levels in both mouse models.
Main Results:
- MMI treatment increased ciliogenesis and LRP2/megalin expression in thyroid follicular cells, with LRP2/megalin localized to primary cilia.
- Thyroid glands with defective primary cilia (Tg-Cre;Ift88 mice) showed significantly lower LRP2/megalin levels.
- Serum Tg levels were elevated in MMI-treated mice and reduced in Tg-Cre;Ift88 mice.
Conclusions:
- Primary cilia are crucial for LRP2/megalin expression and localization in thyroid follicular cells.
- Primary cilia play a significant role in TSH-mediated thyroglobulin endocytosis.
- Defective ciliogenesis impairs LRP2/megalin-mediated Tg uptake, affecting thyroid hormone homeostasis.
Related Concept Videos
01:20Synthesis and Regulation of Thyroid Hormones
5.8K
Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
5.8K
01:23The Thyroid Gland
5.0K
The thyroid gland is a small, butterfly-shaped gland located in the neck and covers the anterior surface of the trachea. The gland has two lateral lobes connected by a thin tissue mass called the isthmus. Internally, each lobe comprises many small spherical structures known as thyroid follicles, surrounded by a network of blood vessels.
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
5.0K
01:22Protein Transport to the Thylakoids
2.5K
Thylakoids are membrane-bound sac-like structures within the chloroplast that serve as sites for photosynthesis. Thylakoid lumen contains many electron transport proteins and is enclosed by a thylakoid membrane rich in the light-harvesting complex. Proteins targeted to the thylakoids are transported as precursors and are sorted by the general TOC/TIC import pathway. Once the precursor reaches the stroma, stromal processing peptidases remove their transit signal and expose thylakoid signal...
2.5K
01:18Functions of Thyroid Hormones
3.7K
The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
3.7K
01:28The Early Endosome: Endocytosis of Transferrin
3.8K
Essential proteins such as insulin or low-density lipoprotein (LDL) and micronutrients such as iron enter a eukaryotic cell through receptor-mediated endocytosis. Subsequently, the early endosomes fuse with the vesicles containing such receptor-ligand complexes and play a vital role in sorting the incoming ligands and receptors. While the ligands are either degraded inside the vesicle or released into the cytosol, their receptors are returned to the plasma membrane for further rounds of...
3.8K
01:22Microtubules in Signaling
1.8K
The primary cilium, made up of microtubules, acts as antennae on the cell surfaces for relaying external stimuli into the cells. These fine hair-like structures are present, generally one per cell. These are non-motile cilia in a 9+0 microtubules arrangement, where the central pair of microtubules are absent. The primary cilia arise from the basal body embedded in the cell membrane. Intraflagellar transport (IFT) carries requisite proteins from the cytoplasm to the cilium because the primary...
1.8K