Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 1991 Feb 1;88(3):1039-43.
doi: 10.1073/pnas.88.3.1039.

Cloning by differential screening of a Xenopus cDNA coding for a protein highly homologous to cdc2

J Paris  1 , R Le Guellec, A Couturier, K Le Guellec, F Omilli, J Camonis, S MacNeill, M Philippe
Affiliations
Comparative Study

Cloning by differential screening of a Xenopus cDNA coding for a protein highly homologous to cdc2

J Paris et al. Proc Natl Acad Sci U S A. .

Abstract

Fertilization of Xenopus laevis eggs triggers a period of rapid cell division comprising 12 nearly synchronous mitoses. Protein synthesis is required for these divisions, and new proteins appear after fertilization. Others proteins however, which are synthesized in the unfertilized egg, are no longer made in the early embryo. To identify such proteins, a differential screen of an egg cDNA library gave nine clones corresponding to mRNAs that are deadenylylated soon after fertilization. The sequence of one of these clones (Eg1) revealed a high homology to p34cdc2, the kinase subunit of maturation-promoting factor. Only 12 amino acids in the deduced amino acid sequence were unique to Eg1 when its sequence was compared to all other known examples of cdc2. Despite this strong similarity, however, Eg1 was unable to complement a yeast cdc2- mutant in Schizosaccharomyces pombe or a cdc28 mutant of Saccharomyces cerevisiae. Four Eg1 transcripts, two major and two minor, were found in Xenopus oocytes and early embryos. These RNAs appeared very early (stage I) in oogenesis and their level remained constant until the midblastula transition, at which time they declined. Eg1 RNA is found in the poly(A)+ fraction of oocytes only between the time of meiotic maturation and fertilization--that is to say, in the unfertilized egg. At fertilization the RNA loses its poly(A) tail and at the same time leaves the polyribosomes.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Gene. 1984 Nov;31(1-3):129-34 - PubMed
    1. Mol Gen Genet. 1976 Jul 23;146(2):167-78 - PubMed
    1. Proc Natl Acad Sci U S A. 1990 Aug;87(15):5697-701 - PubMed
    1. Nature. 1990 Apr 5;344(6266):503-8 - PubMed
    1. Dev Biol. 1990 Jul;140(1):221-4 - PubMed

Publication types

MeSH terms

LinkOut - more resources