Expression of DNA ligases I and II during oogenesis and early development of Xenopus laevis.
We have analyzed the expression of DNA ligase I protein during oogenesis and early development of Xenopus laevis. The protein is already present in stage I oocytes and then accumulates throughout oogenesis to reach a steady state level by stage VI. It remains at this level at least until tadpole stage. In stage VI oocytes DNA ligase I protein is almost exclusively localized in the germinal vesicle. We have partially purified a DNA ligase II activity from stage VI oocytes, unfertilized eggs, and stage 8 embryos. An 80-kDa polypeptide can be specifically adenylated in all three purified extracts. It is not recognized by antibodies directed against DNA ligase I and is active on oligo(dT)-poly(rA) substrate. It could therefore represent DNA ligase II protein. The presence of both DNA ligases I and II in oocytes and embryos is inconsistent with the DNA ligase model that had been previously proposed for amphibia.
Aoufouchi
S
S
Laboratoire de Biologie et Génétique du Développement, URA CNRS 256, Université de Rennes I, France.
Prigent
C
C
Theze
N
N
Philippe
M
M
Thiebaud
P
P
D000818:Animals; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000032:analysis*; D007814:Larva; D009866:Oogenesis / Q000502:physiology*; D014982:Xenopus laevis / Q000196:embryology* / Q000378:metabolism
D011088:DNA Ligases; D000072481:DNA Ligase ATP