Benbow R M, Ford C C
Proc Natl Acad Sci U S A. 1975 Jun;72(6):2437-41. doi: 10.1073/pnas.72.6.2437.
Nuclei isolated from nondividing cells were induced to synthesize DNA by incubation with cytoplasm from early embryos of Xenopus laevis. Numerous replication eyes were formed in the nuclear DNA molecules, and high levels of [3-H]dTTP were incorporated. With this assay a protein(s) which appears to initiate DNA synthesis was found at high levels in the cytoplasm of eggs, blastulae, or gastrulae, but only at low levels in the cytoplasm of oocytes, hatched embryos, or adult tissues.
从非分裂细胞中分离出的细胞核，通过与非洲爪蟾早期胚胎的细胞质一起孵育，被诱导合成DNA。在核DNA分子中形成了许多复制眼，并且掺入了高水平的[3-H]dTTP。通过该测定法发现，一种似乎启动DNA合成的蛋白质在卵、囊胚或原肠胚的细胞质中含量很高，但在卵母细胞、孵化后的胚胎或成体组织的细胞质中含量很低。
