Details

Autor(en) / Beteiligte

• Unuma, T.
• Arendell, J.P.
• Busch, H.

Titel

High resolution autoradiographic studies of the uptake of 3H-5-uridine into condensed and dispersed chromatin of nuclei and granular and fibrillar components of nucleoli of Novikoff hepatoma ascites cells

Ist Teil von

• Experimental cell research, 1968-10, Vol.52 (2), p.429-438

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

1968

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• Novikoff hepatoma cells were incubated in vivo with 3H-5-uridine from 5 min to 6 h to permit a kinetic analysis of the distribution of the isotope over the ultrastructural components of the nucleus and the nucleolus. After a 5 min pulse, 75 per cent of the total grains in the nucleolus were localized over the fibrillar components. The percentage of the grains over the fibrillar components decreased to 30 per cent of the total in the nucleolus after a 60 min pulse. The percentage of the grains over the nucleolar granular components increased from 13 per cent of the total at 5 min to approx. 50 per cent at 1h. The remainder of the grains over the perinucleolar nucleolus-associated chromatin increased from 12 per cent of the total in the nucleoli at 5 min to 24 per cent at 60 min. The overall nuclear dispersed chromatin contained approx. twice as much isotope as the condensed chromatin over the prolonged period of 15 min to 6 h. The greater labeling of the fibrillar components of the nucleoli suggests that initial biosynthetic reactions occur in these regions as suggested by Granboulan and Granboulan [4] and by Geuskens and Bernhard [3]. Earlier kinetic studies from this laboratory [6] indicated that there is rapid transfer of long chain nucleolar elements to granular components.