Wasylyk B, Imler J L, Chatton B, Schatz C, Wasylyk C
Laboratoire de Génétique Moléculaire des Eucaryotes, l'Institut National de la Santé et de la Recherche Medicale, Faculté de Médecine, Strasbourg, France.
Proc Natl Acad Sci U S A. 1988 Nov;85(21):7952-6. doi: 10.1073/pnas.85.21.7952.
The host range of polyoma virus is dependent upon the activity of its enhancer, which is inactive in undifferentiated embryonal carcinoma cells, such as F9 cells, and is active after their differentiation. We show here that the activity of the alpha domain of the polyoma virus enhancer displays a similar cell-specificity and inducibility as does the whole enhancer. We present evidence to show that its activity is determined by the balance between the activities of two factors, PEA2, a labile repressor, and PEA1, an inducible positive factor that we have characterized previously. Changes in repressor activity help account for the increase in alpha-domain activity after differentiation of F9 cells. These results suggest that PEA2 is crucial in the regulation of viral gene expression and perhaps more generally in the control of gene expression during differentiation.
多瘤病毒的宿主范围取决于其增强子的活性，该增强子在未分化的胚胎癌细胞（如F9细胞）中无活性，而在其分化后具有活性。我们在此表明，多瘤病毒增强子α结构域的活性与整个增强子一样，表现出相似的细胞特异性和可诱导性。我们提供证据表明，其活性由两个因子活性之间的平衡决定，即不稳定的阻遏因子PEA2和我们之前已鉴定的可诱导的正因子PEA1。阻遏因子活性的变化有助于解释F9细胞分化后α结构域活性的增加。这些结果表明，PEA2在病毒基因表达的调控中至关重要，或许在更广泛的分化过程中基因表达的控制中也起着关键作用。
