RNA transcription of isolated nuclei and chromatin with exogenous RNA polymerases during mitotic cycle and encystment ofPhysarum polycephalum.
Wilehm Roux Arch Dev Biol
; 187(3): 195-209, 1979 Sep.
Article
en En
| MEDLINE
| ID: mdl-28305077
Nuclei have been isolated from plasmodia ofPhysarum. Chromatin has been prepared from these nuclei by lysing them gently with lysolecithin. Both nuclei and chromatin contain endogenous activities of RNA polymerases A and C but not of RNA polymerase B under the conditions specifiied. RNA synthesis of chromatin and nuclei can be stimulated by the addition of purified RNA polymerases. RNA polymerase B is significantly more active than A or the bacterial RNA polymerase fromEscherichia coli. Experiments with specific inhibitors indicate that this additional RNA transcription is due to initiation by exogenously supplied RNA polymerase B. Large RNA products (up to 30 S when analysed under denaturating conditions) are transcribed on chromatin.The template activity of nuclei or chromatin, measured using saturating amounts of added RNA polymerase B, correlates with the in vivo RNA synthesis in three well defined situations. It decreases during starvation when the plasmodium prepares for encystment and is very low during mitosis, however, it is very high during the S-phase of the mitotic cycle when the highest activity of poly(A) + RNA synthesis is detected.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Wilehm Roux Arch Dev Biol
Año:
1979
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Alemania