Tscheudschilsuren G, Küchenhoff A, Klonisch T, Tetens F, Fischer B
Department of Anatomy and Cell Biology, Martin Luther University Faculty of Medicine, Halle (Saale), D-06097, Germany.
Toxicol Appl Pharmacol. 1999 Jun 1;157(2):125-33. doi: 10.1006/taap.1999.8667.
The arylhydrocarbon receptor (AhR) is a ligand-activated transcription factor and mediates carcinogenic, teratogenic, and toxic effects of xenobiotics such as dioxin and coplanar polychlorinated biphenyls. The AhR nuclear translocator (ARNT) is involved in AhR signal transduction. We have analyzed the expression of AhR and ARNT mRNA and AhR protein in Day 3 pc (postcoitum) rabbit morulae and Days 4 and 6 pc blastocysts using RT-PCR, nested PCR, whole mount in situ hybridization, and whole mount immunohistochemistry with subsequent confocal laser scanning analysis. AhR and ARNT transcripts were detected in all stages investigated, indicating coexpression of both transcription factors. AhR protein was localized in the cytoplasm. It was detected in Day 3 pc morulae and in blastocysts. In Day 4 pc blastocysts, only trophoblast cells but not embryoblast cells were immunopositive. However, at Day 6 pc, the embryoblast cells also expressed AhR protein and this expression was correlated with the degeneration of Rauber's trophoblast layer.
芳基烃受体（AhR）是一种配体激活的转录因子，介导诸如二恶英和共平面多氯联苯等外源性物质的致癌、致畸和毒性作用。AhR核转运蛋白（ARNT）参与AhR信号转导。我们使用逆转录聚合酶链反应（RT-PCR）、巢式PCR、全胚胎原位杂交以及全胚胎免疫组织化学并随后进行共聚焦激光扫描分析，分析了妊娠3天（合子后）兔桑椹胚以及妊娠4天和6天囊胚中AhR和ARNT mRNA及AhR蛋白的表达。在所研究的所有阶段均检测到AhR和ARNT转录本，表明这两种转录因子共表达。AhR蛋白定位于细胞质中。在妊娠3天的桑椹胚和囊胚中均检测到该蛋白。在妊娠4天的囊胚中，只有滋养层细胞呈免疫阳性，而内细胞团细胞则否。然而，在妊娠6天，内细胞团细胞也表达AhR蛋白，且这种表达与朗汉斯滋养层的退化相关。
