Zandvliet D W, Hanby A M, Austin C A, Marsh K L, Clark I B, Wright N A, Poulsom R
ICRF Histopathology Unit, London, UK.
Biochim Biophys Acta. 1996 Jun 7;1307(2):239-47. doi: 10.1016/0167-4781(96)00063-2.
We present the first analysis of the sites of expression of DNA topoisomerase II alpha and II beta mRNAs in human foetal tissues by in situ hybridisation, using 35S-radiolabelled probes. This revealed differential localisation of topoisomerase II alpha and II beta mRNAs in a range of foetal organs, including foetal kidney (developing structures within the neogenic zone), brain (cortical layers), small intestine (crypt epithelium and muscle), liver (hepatocytes), lung (smooth muscle, and epithelium in the lining of primitive lung buds) and placenta (trophoblastic epithelium). The intensity of expression of topoisomerase II alpha mRNA appeared higher than that of topoisomerase II beta, although topoisomerase II beta mRNA was expressed in a broader range of cell types. The distinct patterns of expression of topoisomerase II alpha and beta mRNAs indicate differential regulation of these genes, suggesting that the two isoforms may play important but different roles in foetal development, with topoisomerase II alpha being expressed most strongly in zones of proliferation.
我们使用35S放射性标记探针，通过原位杂交技术首次分析了人胎儿组织中DNA拓扑异构酶IIα和IIβ mRNA的表达位点。这揭示了拓扑异构酶IIα和IIβ mRNA在一系列胎儿器官中的差异定位，包括胎儿肾脏（新生区的发育结构）、大脑（皮质层）、小肠（隐窝上皮和肌肉）、肝脏（肝细胞）、肺（平滑肌和原始肺芽内衬的上皮）和胎盘（滋养层上皮）。尽管拓扑异构酶IIβ mRNA在更广泛的细胞类型中表达，但拓扑异构酶IIα mRNA的表达强度似乎高于拓扑异构酶IIβ。拓扑异构酶IIα和β mRNA的不同表达模式表明这些基因受到差异调控，这表明这两种同工型可能在胎儿发育中发挥重要但不同的作用，其中拓扑异构酶IIα在增殖区域表达最强。
