Molecular Histo-cytochemical Analysis of Gene Transcription Factors Reflecting in the Regulation of Functional Differentiation of the Cell

1. 在妊娠期，胎盘的毛囊细胞分化为表达催乳素家族蛋白基因的绒毛细胞。为了弄清增强基因表达的转录因子Pit-1的细胞分布差异是否反映了分化细胞的状态，我们进行了西南组织化学，该方法定位了dna结合转录因子。在妊娠后期的大鼠胎盘中，具有核内Pit-1的绒毛细胞似乎与细胞质中表达催乳素家族蛋白基因的绒毛细胞相同。为了进一步了解分化细胞中核成分与转录因子核内状态的关系，我们在超微结构水平上进行了西南组织化学。dna结合坑1定位于表达催乳素家族蛋白基因的绒毛膜绒毛细胞和表达催乳素基因的垂体前叶细胞的细胞核的正染色质上。这表明，dna结合转录因子在常染色质中的定位对细胞的功能分化至关重要。为了分析dna结合转录因子与基因组dna或转录本之间的核内位点关系，作为模型，对两种不同的核酸进行了超微结构定位。由于45S rRNA与18S rRNA和28S rRNA进行了化学对称剪接，我们使用不同大小的胶体金颗粒在原位杂交的后包埋方法中检测了这两种rRNA在小鼠睾丸组织切片中的同时定位。电镜原位杂交显示，这些rna在支持细胞核仁中的分布存在差异。我们的研究结果表明，通过该方法可以定量地显示核中具有不同代谢的核物质，如rrna以及转录因子和转录本的相互分布。少

1. During the gestation, the ehorionie cells of placentas differentiate into the villous cells which express the prolactin family protein gene. To clarify whether difference of cellular distribution of a transcription factor, Pit-1, which enhances expression of the gene reflects the state of the differentiating cells, we performed Southwestern histochemistry of which method localizes DNA-binding transcription factors. In rat placentas at the late gestational days, the villous cells possessing intranuclear Pit-1 seemed to be identical to the villous cells expressing the prolactin family protein genes in their cytoplasm.2. To understand further the relationship between nuclear components and intranuclear state of transcription factors in differentiating cells, Southwestern histochemistry was performed at ultrastruetural level. The DNA-binding Pit 1 was localized in the euchroraatin of nuclei both of the chorionic villous cells which express prolactin family protein genes and of anterior … More pituitary cells which express prolactin gene. It is suggested that the localization of DNA-binding transcription factors in euchromatin in which the active chromatins are located would be essential for functional differentiation of the cells.3. To analyze a relationship of intranuclear sites between DNA-binding transcription factors and the genomic DNAs or the transcripts, as a model, two different nucleic acids were ultrastructurally localized. Since 45S rRNA is stoichyometrically spliced to 18S rRNA and 28S rRNA, we examined simultaneous localization of both rRNAs in mouse testicular tissue sections using different sized colloidal gold particles in post-embedding method of in situ hybridization. Electron microscopic in situ hybridization revealed that different distribution between these rRNAs was seen in the nucleoli of Sertoli cells. Our findings suggest that the mutual distribution of nuclear substances with different metabolisms, such as the rRNAs as well as the transcription factors and the transcripts, would be quantitatively demonstrated in the nuclei by the method. Less