Determination and synchronisation of G1-phase of the cell cycle in 2- and 4-cell mouse embryos

Yuansong Yu, Ping Xia, Shufent Li, Yunqin Yan, Jinghe Tan

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


Incorporation of [3H]thymidine at different concentrations into mouse embryos at early developmental stages was determined by autoradiography. Methods to synchronise the G1-phase of mouse 2- and 4-cell embryos were also investigated. The results showed that the ability of embryos to incorporate [3H]thymidine increased with development. Embryos at the 4-cell stage were not labelled when the concentration of [3H]thymidine was lower than 5 μCi/ml, whereas the nuclei of embryos at morula and blastocyst stages began to show silver grains at a concentration of 0.1 μCi/ml of [3H]thymidine. After 2- and 4-cell mouse embryos were synchronised at the onset of G1-phase by treatment with low temperature or nocodazole, and DNA synthesis was detected by autoradiography, the duration of G1-phase was estimated. The result showed that 43% of the 2-cell embryos had a G1-phase of < 1 h, 22% had a G1-phase of < 2 h, 22% had a G1-phase of < 3 h and 13% had a G1-phase of < 4 h. The G1-phase in 85% of the 4-cell embryos was < 3 h, that in 8% of embryos was < 4 h and that in 7% of embryos was < 5 h. The toxicity of nocodazole on mouse embryo development was assessed based on both blastocyst formation and the number of blastomeres, and the results indicated that the effect of nocodazole on embryo development and cell cycle block was dose-dependent. The minimum concentration of nocodazole for metaphase block of mouse late 2-cell embryos was 0.05 μM, and the appropriate concentrations which did not impair development were 0.05-0.5 μM.

Original languageEnglish (US)
Pages (from-to)245-251
Number of pages7
Issue number3
StatePublished - Aug 2002
Externally publishedYes


  • DNA synthesis
  • Embryos
  • G1-phase
  • Mouse
  • Nocodazole

ASJC Scopus subject areas

  • Developmental Biology
  • Cell Biology


Dive into the research topics of 'Determination and synchronisation of G1-phase of the cell cycle in 2- and 4-cell mouse embryos'. Together they form a unique fingerprint.

Cite this