Grouse L D, Schrier B K, Letendre C H, Zubairi M Y, Nelson P G
J Biol Chem. 1980 May 10;255(9):3871-7.
The cholinergic mouse neuroblastoma cell line NS20Y was adapted to undifferentiated growth in suspension culture. When suspension cells were transferred to surface culture and treated with dibutyryl cyclic AMP, the cells underwent differentiation as assessed by biochemical, morphological, and physiological criteria. Differentiated NS20Y cells in co-culture with mouse muscle cells had the capacity to form functional neuromuscular junctions with the muscle cells. The sequence complexities of the poly(A)-containing messenger RNA (poly(A)+ mRNA) of the differentiated, process-forming cells (P-cells) and undifferentiated cells in suspension culture (S-cells) were measured by analysis of the kinetics of hybridization of the mRNAs with their complementary DNAs (cDNAs). There were less than 100 high abundance and approximately 8000 low abundance poly(A)+ mRNAs in both differentiation states. Heterologous hybridization reactions and recycling of the cDNA probes revealed that 9.7% and 6.8% of the messages in P- and S-cells, respectively, were specific to those differentiation states. The P-cell-specific sequences included approximately 3 high abundance and 320 low abundance poly(A)+ mRNAs. The S-cell-specific sequences included approximately 3 high abundance and 250 low abundance poly(A)+ mRNAs. We conclude that the increment in NS20Y differentiation results in both the disappearance of old, and the appearance of new mRNAs in polyribosomes.
胆碱能小鼠神经母细胞瘤细胞系NS20Y被改造以适应悬浮培养中的未分化生长。当悬浮细胞转移至贴壁培养并用二丁酰环磷腺苷处理时，通过生化、形态学和生理学标准评估，细胞发生了分化。与小鼠肌肉细胞共培养的分化型NS20Y细胞有能力与肌肉细胞形成功能性神经肌肉接头。通过分析分化型、有突起形成的细胞（P细胞）和悬浮培养的未分化细胞（S细胞）中含聚腺苷酸的信使核糖核酸（聚腺苷酸+ mRNA）的杂交动力学，测量了它们的序列复杂性。在两种分化状态下，高丰度的聚腺苷酸+ mRNA均少于100种，低丰度的约有8000种。异源杂交反应和cDNA探针的循环利用表明，P细胞和S细胞中分别有9.7%和6.8%的信息是这些分化状态所特有的。P细胞特异性序列包括约3种高丰度和320种低丰度的聚腺苷酸+ mRNA。S细胞特异性序列包括约3种高丰度和250种低丰度的聚腺苷酸+ mRNA。我们得出结论，NS20Y分化的增加导致多核糖体中旧mRNA的消失和新mRNA的出现。
