- Made available online as an Accepted Preprint 3 February 2011
Local control of thyroid hormone action: role of type 2 deiodinase
Deiodinases: the balance of thyroid hormone
- Molecular Endocrinology Group, Department of Medicine and Medical Research Council Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, Commonwealth Building 7th Floor, Du Cane Road, London W12 0NN, UK
- (Correspondence should be addressed to G R Williams; Email: graham.williams{at}imperial.ac.uk)
Abstract
The thyroid gland predominantly secretes the pro-hormone thyroxine (T4) that is converted to the active hormone 3,5,3′-l-triiodothyronine (T3) in target cells. Conversion of T4 to T3 is catalyzed by the type 2 iodothyronine deiodinase enzyme (DIO2), and T3 action in target tissues is determined by DIO2-regulated local availability of T3 to its nuclear receptors, TRα and TRβ. Studies of Dio2 knockout mice have revealed new and important roles for the enzyme during development and in adulthood in diverse tissues including the cochlea, skeleton, brown fat, pituitary, and hypothalamus. In this review, we discuss the molecular mechanisms by which DIO2 controls intracellular T3 availability and action.
- Received in final form 20 January 2011
- Accepted 3 February 2011
- © 2011 Society for Endocrinology
