Moscinski L C, Prystowsky M B
Department of Pathology, University of Pennsylvania, Philadelphia 19104.
Oncogene. 1990 Jan;5(1):31-7.
The production of terminally differentiated granulocytes and monocytes occurs by a program of orderly and sequential gene expression. This genetic program can be studied in vitro utilizing granulocyte-monocyte colony stimulating factor (GM-CSF) to stimulate proliferation and myeloid cell maturation. We have identified a series of genes expressed during early myeloid differentiation by differential screening of a cDNA library prepared from GM-CSF stimulated murine progenitor cells. From 72 potential early myeloid specific clones, three (B9, C9, C15) were characterized further. The time course of RNA accumulation during GM-CSF stimulated maturation demonstrated a unique pattern for each clone. B9 was expressed predominantly on day 3, and followed a pattern of accumulation similar to that for myeloperoxidase. (Jaffe et al. (1988), Oncogene, 2, 167-174). C9 expression increased gradually to a maximum level on day 3 and then plateaued; it appeared to be equally expressed in granulocytes and monocytes. C15 was expressed at a consistently high level in unstimulated cells and at 1-3 days post GM-CSF stimulation. It then decreased to undetectable levels. Hybridization of these clones to a panel of murine tissue RNAs demonstrated restricted expression of B9 to bone marrow, while C9 was present in most murine tissues, including thymus. C15 expression was relatively restricted to ovary/uterus, liver and adrenal, in addition to bone marrow. Partial DNA sequence analysis suggested that B9 was a novel sequence not previously identified. C9 was identified as thymosin beta-4, and C15 showed extensive homology to lactotransferrin. Thus, screening a bone marrow cDNA library by differential hybridization has successfully yielded a series of DNA sequences regulated during murine myelopoiesis. These include novel sequences (B9), genes previously known to be regulated during myelopoiesis (C15), as well as sequences not recognized previously as being associated with myeloid differentiation (C9).
终末分化的粒细胞和单核细胞的产生是通过有序且连续的基因表达程序实现的。这个遗传程序可以在体外利用粒细胞 - 单核细胞集落刺激因子（GM - CSF）来刺激增殖和髓样细胞成熟进行研究。我们通过对从GM - CSF刺激的小鼠祖细胞制备的cDNA文库进行差异筛选，鉴定出了一系列在早期髓样分化过程中表达的基因。从72个潜在的早期髓样特异性克隆中，进一步对三个克隆（B9、C9、C15）进行了表征。GM - CSF刺激成熟过程中RNA积累的时间进程显示每个克隆都有独特的模式。B9主要在第3天表达，其积累模式与髓过氧化物酶相似。（贾菲等人（1988年），《癌基因》，2，167 - 174）。C9的表达在第3天逐渐增加到最高水平，然后趋于平稳；它似乎在粒细胞和单核细胞中表达水平相当。C15在未刺激的细胞中以及GM - CSF刺激后1 - 3天持续高水平表达。然后它下降到检测不到的水平。这些克隆与一组小鼠组织RNA的杂交表明，B9仅在骨髓中表达，而C9存在于大多数小鼠组织中，包括胸腺。除了骨髓外，C15的表达相对局限于卵巢/子宫、肝脏和肾上腺。部分DNA序列分析表明B9是一个以前未鉴定的新序列。C9被鉴定为胸腺素β - 4，C15与乳铁传递蛋白有广泛的同源性。因此，通过差异杂交筛选骨髓cDNA文库成功获得了一系列在小鼠骨髓生成过程中受调控的DNA序列。这些包括新序列（B9）、以前已知在骨髓生成过程中受调控的基因（C15），以及以前未被认为与髓样分化相关的序列（C9）。
