CLEAVAGE ARREST IN XENOPUS EMBRYOS INJECTED WITH A HUMAN C-MYC GENE

The c-myc protein has been implicated in cell proliferation and differentiation of various cell lines, but its function in early embryos of Xenopus is obscure. We introduced the c-myc gene into embryos using a pcDL- SR(α) plasmid with an efficient promoter of the gene. It was found that fertilized eggs injected with the c-myc gene were arrested at the 4-cell stage within 1 h of the injection, when the plasmid that carried c-myc gene but not the plasmid that carried defective c-myc gene was injected. These results also suggest that Xenopus embryos already have the ability to transcribe an exogenously injected c-myc gene at the 4-cell stage. © 1993 Academic Press, Inc.