Elba D Carrillo, Juan A Alvarado, Ascención Hernández, Ivonne Lezama, María C García, Jorge A Sánchez
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引用次数: 0
Abstract
Thyroid hormone binds to specific nuclear receptors, regulating the expression of target genes, with major effects on cardiac function. Triiodothyronine (T3) increases the expression of key proteins related to calcium homeostasis, such as the sarcoplasmic reticulum calcium ATPase pump, but the detailed mechanism of gene regulation by T3 in cardiac voltage-gated calcium (Cav1.2) channels remains incompletely explored. Furthermore, the effects of T3 on Cav1.2 auxiliary subunits have not been investigated. We conducted quantitative reverse transcriptase polymerase chain reaction, Western blot, and immunofluorescence experiments in H9c2 cells derived from rat ventricular tissue, examining the effects of T3 on the expression of α1c, the principal subunit of Cav1.2 channels, and Cavβ4, an auxiliary Cav1.2 subunit that regulates gene expression. The translocation of phosphorylated cyclic adenosine monophosphate response element-binding protein (pCREB) by T3 was also examined. We found that T3 has opposite effects on these channel proteins, upregulating α1c and downregulating Cavβ4, and that it increases the nuclear translocation of pCREB while decreasing the translocation of Cavβ4. Finally, we found that overexpression of Cavβ4 represses the mRNA expression of α1c, suggesting that T3 upregulates the expression of the α1c subunit in response to a decrease in Cavβ4 subunit expression.
期刊介绍:
The International Journal of Molecular Sciences (ISSN 1422-0067) provides an advanced forum for chemistry, molecular physics (chemical physics and physical chemistry) and molecular biology. It publishes research articles, reviews, communications and short notes. Our aim is to encourage scientists to publish their theoretical and experimental results in as much detail as possible. Therefore, there is no restriction on the length of the papers or the number of electronics supplementary files. For articles with computational results, the full experimental details must be provided so that the results can be reproduced. Electronic files regarding the full details of the calculation and experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material (including animated pictures, videos, interactive Excel sheets, software executables and others).