par Mariano, Enrique E.E.;Doumont, Angèle 
Référence Biochimica et biophysica acta, N. Nucleic acids and protein synthesis, 103, 4, page (610-622)
Publication Publié, 1965-08
Référence Biochimica et biophysica acta, N. Nucleic acids and protein synthesis, 103, 4, page (610-622)
Publication Publié, 1965-08
Article révisé par les pairs
| Résumé : | The content of RNA per nucleus has been determined in the gastrula and neural plate stages of Xenopus laevis. The experiments show that nuclear RNA increases at the mid-gastrula stage. After incubation of the eggs for 20 min in 32P solution, the specific activity of RNA, determined in embryonic cells at the neural plate stage was 33 times greater in the nuclear than in the cytoplasmic fraction. These results suggest that the major part of the RNA is synthesized in the nuclei. Two RNA fractions were separated when embryonic cells at the gastrula and neurula stages were treated with phenol at 45° and 65°. The study of sedimentation pattern and the base composition of both RNA fractions suggest that the labelled RNA separated at 45° is probably, for the most part, a precursor of ribosomal RNA, whereas the RNA fraction separated at 65° may be messenger RNA. Both fractions, ribosomal precursor and messenger RNA, would appear to be metabolically unstable and the degradation process would be greater at the neurula stages than in gastrulae. © 1965. |
