The synthesis of thyroglobulin involves several steps. Initially, it is synthesized in the rough endoplasmic reticulum of the thyroid follicular cells. It is then glycosylated in the Golgi apparatus before being secreted into the follicular lumen.
In the follicular lumen, thyroglobulin undergoes iodination, a process that involves the addition of iodine molecules to tyrosine residues within the thyroglobulin molecule. This iodination is facilitated by the enzyme thyroid peroxidase. Once iodinated, the thyroglobulin is stored in the colloid until the thyroid gland is stimulated to produce thyroid hormones.
