Risek B, Klier F G, Phillips A, Hahn D W, Gilula N B
Department of Cell Biology, Scripps Research Institute, La Jolla, CA 92037, USA.
J Cell Sci. 1995 Mar;108 ( Pt 3):1017-32. doi: 10.1242/jcs.108.3.1017.
The effects of estrogen (E2) and progesterone (P) were examined on the expression levels of multiple gap junction (GJ) gene products (alpha 1 = Cx43, beta 1 = Cx32, beta 2 = Cx26) in the uterus and ovaries of immature rats by immunohistochemistry, electron microscopy and northern blot analysis. E2 induced the expression of alpha 1 connexin in the uterus (specifically in the myometrium and in endometrial stroma proximal to luminal epithelium) and ovaries. The E2-induced alpha 1 expression was completely suppressed by P in the uterus, but only partly in ovaries. Steroid hormones also modulated the quantity, size, and distribution of beta 1 and beta 2 containing junctional plaques along lateral cell borders in polarized luminal and glandular uterine epithelia. Small GJs were detected at basolateral regions in proliferative luminal epithelium following administration of E2. In contrast, large GJs were localized at subapical-lateral cell borders of the secretory epithelium following P-treatment. The co-administration of E2 + P had a synergistic effect on beta 1 and beta 2 expression in the luminal epithelium, but an inhibitory effect on beta 2 expression in glandular epithelium. Myometrial GJs were detected in freeze-fracture replicas as aggregates containing regularly arranged particles with particle free zones. In contrast, GJs in secretory epithelium contained particles which were arranged in a non-crystalline fashion. These GJs contained domains of mixed and segregated beta 1 and beta 2 antigens within a single plaque as revealed by laser scanning confocal microscopy analysis of immuno-double-labeled secretory epithelium. The demonstration of segregated antigens within a single GJ plaque indicates the possibility of multiple channel populations formed by homo-oligomeric connexons. These results suggest that different connexins can be differentially regulated by steroid hormones in different cell types, and that the same steroid hormone can have different effects on the same connexin in different cell types.
通过免疫组织化学、电子显微镜和Northern印迹分析，研究了雌激素（E2）和孕酮（P）对未成熟大鼠子宫和卵巢中多种缝隙连接（GJ）基因产物（α1 = Cx43，β1 = Cx32，β2 = Cx26）表达水平的影响。E2诱导子宫（特别是子宫肌层和靠近腔上皮的子宫内膜基质）和卵巢中α1连接蛋白的表达。E2诱导的α1表达在子宫中被P完全抑制，但在卵巢中仅部分被抑制。类固醇激素还调节了极化的腔和腺性子宫上皮细胞侧面边界处含β1和β2的连接斑的数量、大小和分布。给予E2后，在增殖性腔上皮的基底外侧区域检测到小的GJ。相反，P处理后，大的GJ位于分泌上皮的顶端下外侧细胞边界。E2 + P联合给药对腔上皮中β1和β2的表达有协同作用，但对腺上皮中β2的表达有抑制作用。在冷冻断裂复制品中，子宫肌层的GJ表现为含有规则排列颗粒且有颗粒-free区的聚集体。相反，分泌上皮中的GJ含有以非晶体方式排列的颗粒。如免疫双标记分泌上皮的激光扫描共聚焦显微镜分析所示，这些GJ在单个斑块内含有混合和分离的β1和β2抗原结构域。单个GJ斑块内分离抗原的证明表明了由同型寡聚连接子形成多个通道群体的可能性。这些结果表明，不同的连接蛋白在不同细胞类型中可受到类固醇激素的差异调节，并且相同的类固醇激素在不同细胞类型中对相同的连接蛋白可产生不同的影响。
