Table 1.
Summary of connexin regulation by nuclear hormone receptor ligands
| Connexin | Nuclear hormone receptor ligand | Effects on connexin gene products | Cell/tissue type |
|---|---|---|---|
| Cx26 | Estrogens progesterone | ↑ (mRNA and protein) | Reproductive tissue |
| ↓ (Protein) | |||
| Progesterone | ↑ (Protein) | Ectopic endometrium | |
| Glucocorticoids | ↑ (mRNA and protein) | Hepatocytes | |
| Retinoic acid | ↑ (mRNA and protein) | Epidermis | |
| Carotenoids | ↑ (Protein) | Embryonic fibroblasts | |
| Cx32 | Estrogens progesterone | ↑ (Protein) | Reproductive tissue |
| ↓ (Protein) | |||
| Estrogens | ↑ (mRNA) | Brain | |
| Androgens | Stabilized localization at PM | Prostate | |
| Glucocorticoids | ↑ (mRNA and protein) | Hepatocytes | |
| Cx36 | Estrogens progesterone | ↑ (mRNA) | Brain |
| ↓ (mRNA) | |||
| Glucocorticoids | ↑ (mRNA) | Pancreas | |
| Cx37 | Progesterone | ↓ (mRNA) | Reproductive tissue |
| Cx40 | T3 | ↑ (mRNA) | Cardiac atria |
| Absence of RARα | ↓ (Protein) | Spermatocytes | |
| Cx43 | Estrogens progesterone | ↑ (mRNA and protein) | Reproductive tissue (contains ERE) |
| ↓ (mRNA and protein) | |||
| Estrogens progesterone | ↑ Localization at PM | Reproductive tissue | |
| ↓ Localization at PM | |||
| Estrogens | ↑ (mRNA) | Brain, cardiac tissue | |
| Androgens | ↑ (Protein) | Testis | |
| Glucocorticoids | ↓ (mRNA) | Pancreas | |
| Glucocorticoids | Phosphorylation via MAPK | Tissue-specific effects | |
| Low levels of aldosterone | ↑ (mRNA and protein) | Ventricular myocytes | |
| T3 | ↑ (Protein) | Cardiomyocytes | |
| T3 | ↑ (mRNA and protein) | Sertoli cells | |
| Vitamin D | Induce differentiation | Bone marrow | |
| RAR | Stimulate promoter activity | Embryonal carcinoma cells (contain RARE) | |
| Retinoic acid | ↑ (mRNA and protein) | Epidermis, embryonic carcinoma cells, canine lens epithelial cells | |
| Absence of RARβ | ↓ (mRNA) | Testis | |
| Carotenoids | ↑ (mRNA) | Fibroblasts | |
| Carotenoids | ↑ (mRNA and protein) | Mammary epithelial cells |
ERE, Estrogen response element; PM, plasma membrane; RARE, retinoic acid response element.