Recombinant Human Thyroxine Binding Globulin Protein Standard (His tag)

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

Thyroxine Binding Globulin (TBG) also called globulin 23 is a glycoprotein that binds thyroid hormones primarily thyroxine (T4) and triiodothyronine (T3). It facilitates the transport of these hormones through the bloodstream to various tissues. This binding globulin has a molecular weight of approximately 54 kDa. TBG is predominantly expressed in the liver and is an essential component within the circulatory system for hormone regulation. Although there is no substance called 'globulin green' TBG plays an important role in maintaining the systemic balance of thyroid hormones.

Biological function summary

The thyroxine-binding globulin helps maintain adequate levels of thyroid hormones in circulation ensuring a ready reserve supply to target tissues. TBG acts as a carrier protein and does not form part of a larger complex. It provides stability to the hormones and prevents their premature clearance from the bloodstream. Without it the availability and functionality of thyroid hormones within the body would be compromised affecting metabolic and growth functions.

Pathways

Thyroxine-binding globulin is critical in the thyroid hormone signaling pathway. This pathway regulates metabolism growth and development through the action of thyroid hormones. TBG is closely related to other hormone-binding proteins such as transthyretin and albumin which also participate in thyroid hormone transport albeit with different affinities. Its presence ensures that these hormones remain available for cellular uptake and action within various tissues influencing energy expenditure and developmental processes.

The function and levels of thyroxine-binding globulin have significant implications in conditions like hypothyroidism and hyperthyroidism. Altered TBG levels either due to genetic variations or external factors can lead to abnormal blood concentrations of thyroid hormones affecting growth and metabolism. In such disorders the interaction between TBG and thyroid hormones becomes critical. TBG levels can be influenced by other proteins like sex hormone-binding globulin (SHBG) which may reflect changes in the hormone-binding protein landscape during disease states contributing to dysregulated hormonal balance.