Mitochondrial T3 receptor and targets.
The demonstration that TRα1 mRNA encodes a nuclear thyroid hormone receptor and two proteins imported into mitochondria with molecular masses of 43 and 28 kDa has brought new clues to better understand the pleiotropic influence of iodinated hormones. If p28 activity remains unknown, p43 binds to T3 responsive elements occurring in the organelle genome, and, in the T3 presence, stimulates mitochondrial transcription and the subsequent synthesis of mitochondrial encoded proteins. This influence increases mitochondrial activity and through changes in the mitochondrial/nuclear cross talk affects important nuclear target genes regulating cell proliferation and differentiation, oncogenesis, or apoptosis. In addition, this pathway influences muscle metabolic and contractile phenotype, as well as glycaemia regulation. Interestingly, according to the process considered, p43 exerts opposite or cooperative effects with the well-known T3 pathway, thus allowing a fine tuning of the physiological influence of this hormone.
INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France; Université de Montpellier, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France. Electronic address: chantal.cabello@inra.fr.
Chantal
C
Wrutniak-Cabello
INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France; Université de Montpellier, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France.
François
F
Casas
INRA, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France; Université de Montpellier, UMR 866 Dynamique Musculaire et Métabolisme, 34060 Montpellier, France.
Gérard
G
Cabello
D000818:Animals; D017209:Apoptosis; D063646:Carcinogenesis / Q000378:metabolism; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D049109:Cell Proliferation; D053263:Gene Regulatory Networks; D006801:Humans; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism*; D008970:Molecular Weight; D020033:Protein Isoforms / Q000378:metabolism; D011988:Receptors, Thyroid Hormone / Q000235:genetics* / Q000378:metabolism; D037021:Thyroid Hormone Receptors alpha / Q000235:genetics / Q000378:metabolism*
D020033:Protein Isoforms; D011988:Receptors, Thyroid Hormone; D037021:Thyroid Hormone Receptors alpha
Glucose regulation; Mitochondria; Mitochondrial T3 receptor; Mitochondrial/nuclear crosstalk; Muscle development