Stephanou A, Sarlis N J, Richards R, Handwerger S
Department of Endocrinology, Children's Hospital Medical Center, Cincinnati, OH 45229.
Biochem Biophys Res Commun. 1994 Jul 29;202(2):772-80. doi: 10.1006/bbrc.1994.1997.
An in vitro model of trophoblast cell differentiation has been used to examine the developmental expression of retinoid receptor mRNAs during the differentiation of human placental cytotrophoblast cells to syncytiotrophoblast cells. The levels of RAR alpha, RAR beta, RXR alpha mRNA increased by 12, 7, and 3 fold, respectively, during trophoblast differentiation, while the levels of RAR gamma mRNA remained relatively constant; and the increase in retinoid receptor mRNA expression preceded the increase in the expression of placental lactogen (hPL), a specific marker of syncytiotrophoblast cells. CRABP-II mRNA levels were lower in cytotrophoblast cells than in syncytiotrophoblast cells. Mobility shift assays demonstrated the appearance of a specific band that bound to a labeled DNA probe containing a retinoic acid responsive element (RARE) that was most intense from nuclear extracts from syncytiotrophoblast cells. These results suggest possible roles for these receptors in the regulation of trophoblast differentiation and hPL gene expression.
一种滋养层细胞分化的体外模型已被用于检测视黄酸受体mRNA在人胎盘细胞滋养层细胞向合体滋养层细胞分化过程中的发育表达。在滋养层分化过程中，RARα、RARβ、RXRα mRNA水平分别增加了12倍、7倍和3倍，而RARγ mRNA水平保持相对恒定；视黄酸受体mRNA表达的增加先于胎盘催乳素（hPL）表达的增加，hPL是合体滋养层细胞的一种特异性标志物。细胞滋养层细胞中的CRABP-II mRNA水平低于合体滋养层细胞。凝胶迁移试验证明出现了一条与含有视黄酸反应元件（RARE）的标记DNA探针结合的特异性条带，该条带在合体滋养层细胞核提取物中最为明显。这些结果表明这些受体在滋养层分化和hPL基因表达的调控中可能发挥作用。
