This family includes transthyretin that is a thyroid hormone-binding protein that transports thyroxine from the bloodstream to the brain. However, most of the sequences listed in this family do not bind thyroid hormones. They are actually enzymes of ...
This family includes transthyretin that is a thyroid hormone-binding protein that transports thyroxine from the bloodstream to the brain. However, most of the sequences listed in this family do not bind thyroid hormones. They are actually enzymes of the purine catabolism that catalyse the conversion of 5-hydroxyisourate (HIU) to OHCU [2,3]. HIU hydrolysis is the original function of the family and is conserved from bacteria to mammals; transthyretins arose by gene duplications in the vertebrate lineage [4]. HIUases are distinguished in the alignment from the conserved C-terminal YRGS sequence.