Obiettivo Thyroid hormone (T3) acts via thyroid hormone receptors alpha (TRa) and beta (TRb), and is essential for skeletal development and bone mineralisation. T3 excess is associated with an increased risk of osteoporotic fracture and is an important contributor to the morbid and financial burden of disease, although the role of T3 in bone formation and turnover is poorly characterised. The syndrome of resistance to thyroid hormone (RTH) is an autosomal dominant condition that results from dominant negative mutant TRb proteins. Short stature and abnormal skeletal development are prominent features in human RTH. In contrast, TRa mutations have not been described in man and are postulated to be lethal or cause no phenotype. To investigate the mechanisms of T3 action in bone, we will examine bone development in mice with an RTH mutation (PV) targeted to TRb or TRa1 by homologous recombination.Our initial work has shown that TRbPV mice recapitulate human RTH but display skeletal thyrotoxicosis, whilst TRa1PV mice exhibit miled thyroid failure, normal circulating hormone concentrations and skeletal hypothyroidism. Thus, TRa1 and TRb PV mutant mice afford a unique opportunity to characterise T3 action in skeletal cells. In this Outgoing International Fellowship, I will work in two world-leading laboratories in the USA and UK to i) identify skeletal T3-targel genes by RNA microarray analysis and subtraction hybridisation, ii) identify T3-reponse elements in the promoter regions of target genes, iii) characterise the molecular interactions of wild-type and PV mutant TRs at target gene promoters by chromatin immunoprecipitation and iv) analyse the expression of new skeletal T3-target genes in TRa1 and TRb wild-type and mutant mice during development and in response to alterations in thyroid status. The successful achievement of these objectives is dependent on mobility outside Europe and this Fellowship will clearly strengthen and diversify EU scientific excellence. Campo scientifico natural sciencesbiological sciencesbiochemistrybiomoleculesproteinsnatural sciencesbiological sciencesgeneticsmutationnatural sciencesbiological sciencesgeneticsRNA Programma(i) FP6-MOBILITY - Human resources and Mobility in the specific programme for research, technological development and demonstration "Structuring the European Research Area" under the Sixth Framework Programme 2002-2006 Argomento(i) MOBILITY-2.2 - Marie Curie Outgoing International Fellowships (OIF) Invito a presentare proposte FP6-2002-MOBILITY-6 Vedi altri progetti per questo bando Meccanismo di finanziamento OIF - Marie Curie actions-Outgoing International Fellowships Coordinatore IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY AND MEDICINE Contributo UE Nessun dato Indirizzo South Kensington Campus LONDON Regno Unito Mostra sulla mappa Costo totale Nessun dato