Wolffe A P
Department of Embryology, Carnegie Institution of Washington, Baltimore, MD 21210.
EMBO J. 1988 Apr;7(4):1071-9. doi: 10.1002/j.1460-2075.1988.tb02915.x.
An extract of whole oocytes (oocyte S150) differentially transcribes Xenopus oocyte and somatic 5S RNA genes. In the oocyte S150, transcription complexes with different stabilities are assembled onto oocyte and somatic 5S DNA. The stability of the transcription complex is dependent on activities present in a fraction containing transcription factor TFIIIC. This fraction stabilizes the binding of the positive transcription factor TFIIIA to a somatic 5S RNA gene much more efficiently than it does to an oocyte gene. The oocyte S150 transcription extract is deficient in TFIIIC such that supplementation with a fraction enriched in this transcription factor selectively stimulates oocyte 5S DNA transcription. Previously it has been shown that an egg extract deficient in TFIIIA selectively transcribes somatic 5S RNA genes. Thus under conditions where there is differential stability of transcription complexes, limitation of either TFIIIA or TFIIIC may exaggerate the differential expression of two genes.
完整卵母细胞提取物（卵母细胞S150）可差异转录非洲爪蟾卵母细胞和体细胞5S RNA基因。在卵母细胞S150中，具有不同稳定性的转录复合物被组装到卵母细胞和体细胞5S DNA上。转录复合物的稳定性取决于含有转录因子TFIIIC的组分中的活性。该组分比其对卵母细胞基因更有效地稳定正转录因子TFIIIA与体细胞5S RNA基因的结合。卵母细胞S150转录提取物缺乏TFIIIC，因此补充富含该转录因子的组分可选择性地刺激卵母细胞5S DNA转录。先前已表明，缺乏TFIIIA的卵提取物可选择性转录体细胞5S RNA基因。因此，在转录复合物稳定性存在差异的条件下，TFIIIA或TFIIIC的限制可能会夸大两个基因的差异表达。
