Ollo R, Maniatis T
Proc Natl Acad Sci U S A. 1987 Aug;84(16):5700-4. doi: 10.1073/pnas.84.16.5700.
The product of the Drosophila segmentation gene Krüppel was produced in cultured insect cells using the baculovirus expression system. When a cloned Krüppel cDNA sequence was inserted into the viral genome downstream from the promoter of the polyhedrin gene, a polypeptide with an apparent molecular weight of approximately equal to 72,000 was observed in the nuclei of infected cells. Antibodies were raised against this protein and used to detect Krüppel in Drosophila embryos. Characterization of the Krüppel protein extracted from infected cells showed that it is tightly bound to the nucleus, it binds to calf thymus DNA-cellulose, and it is phosphorylated. These results support the hypothesis that Krüppel is a regulatory protein that acts by binding DNA.
利用杆状病毒表达系统在培养的昆虫细胞中产生了果蝇分节基因Krüppel的产物。当将克隆的Krüppel cDNA序列插入多角体蛋白基因启动子下游的病毒基因组中时，在受感染细胞的细胞核中观察到一种表观分子量约为72,000的多肽。制备了针对该蛋白的抗体，并用于检测果蝇胚胎中的Krüppel。对从受感染细胞中提取的Krüppel蛋白的特性分析表明，它与细胞核紧密结合，能与小牛胸腺DNA-纤维素结合，并且被磷酸化。这些结果支持了Krüppel是一种通过结合DNA发挥作用的调节蛋白这一假说。
