Characterization and developmental expression of Xenopus proliferating cell nuclear antigen (PCNA).
Dev Biol
; 141(1): 183-92, 1990 Sep.
Article
em En
| MEDLINE
| ID: mdl-1697269
ABSTRACT
The coding sequence of the proliferating cell nuclear antigen (PCNA) was characterized in the amphibian Xenopus laevis. The deduced protein sequence shares an extensive homology (89%) with the mammalian PCNA coding sequences. Xenopus PCNA is expressed beginning in early oogenesis and reaches a level of 3 X 10(7) transcripts per mature oocyte, whereas proliferative somatic cells contain 3 X 10(2) PCNA transcripts per cell. Most of the PCNA protein is expressed during late oogenesis and one single stage VI oocyte contains the amount of PCNA protein present in 4 X 10(5) somatic cells in culture. Thus most, if not all, of the PCNA required for early development is stored as a maternal gene product. Part of the mRNA stockpile is degraded during the cleavage stage and then new PCNA zygotic expression at the neurula stage maintains a constitutive value of 30 transcripts per cell until the tailbud stage. The maternal protein is maintained at a constant level during embryonic development at least until the swimming tadpole stage. The protein is localized in the nuclei at all stages of oogenesis and development that were examined.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Autoantígenos
/
Xenopus
/
Proteínas Nucleares
Limite:
Animals
Idioma:
En
Revista:
Dev Biol
Ano de publicação:
1990
Tipo de documento:
Article
País de afiliação:
França