[Molecular mechanism of thyroid hormone action].
Thyroid hormones (TH) are involved in normal differentiation, growth, and metabolism in several tissues of all vertebrates. Their actions are mediated by the TH receptors (TRs), members of the nuclear hormone receptor superfamily. These receptors are transcription factors that bind to DNA on specific sequences, the TR response element (TREs), in promoters of target genes. Two genes encode TRs, alpha e beta, located in chromosomes 17 and 3, respectively. These isoforms show different functions and exhibit a tissue specific expression. TRs function as monomers, homodimers or heterodimers with retinoid X receptor (RXR) and modulate transcription activity (repression or activation) by interacting with co-repressor and co-activators, which associate with TR in the absence or presence of T3, respectively. Understanding the molecular mechanism of TR action and the definition of its crystallographic structure will provide new insights into transcription mechanisms and will facilitate the design of new drugs with greater therapeutic value.
Barra
Gustavo B
GB
Laboratório de Farmacologia Molecular, Departamento de Ciências Farmacêuticas, Faculdade de Ciências da Saúde, Universidade de Brasília, Brasília, DF.
Velasco
Lara F R
LF
Pessanha
Rutnéia P
RP
Campos
Alessandra M
AM
Moura
Fanny N
FN
Dias
Sandra M G
SM
Polikarpov
Igor
I
Ribeiro
Ralff C J
RC
Simeoni
Luiz Alberto
LA
Neves
Francisco A R
FA
D000818:Animals; D003461:Crystallography; D005786:Gene Expression Regulation; D006801:Humans; D017434:Protein Structure, Tertiary; D011988:Receptors, Thyroid Hormone / Q000502:physiology; D013963:Thyroid Hormones / Q000235:genetics / Q000502:physiology*
D011988:Receptors, Thyroid Hormone; D013963:Thyroid Hormones