Thyroglobulin is a large, complex protein that is primarily produced in the thyroid gland. It contains two main types of proteins - thyroid peroxidase and thyroglobulin itself. Thyroglobulin plays an important role in the production of thyroid hormones by binding to iodine atoms, which are then incorporated into the hormones T3 (triiodothyronine) and T4 (thyroxine). These hormones regulate metabolism, growth, and development throughout the body.