Number of nascent RNA chains per HeLa cell

Range total ~90,000: active pol I complexes ~15,000: active pol II/III complexes 75,000 complexes/cell
Organism Human Homo sapiens
Reference Jackson DA, Pombo A, Iborra F. The balance sheet for transcription: an analysis of nuclear RNA metabolism in mammalian cells. FASEB J. 2000 Feb14(2):242-54. p.244 left column 2nd paragraphPubMed ID10657981
Primary Source [20] Jackson, D. A., Iborra, F. J., Manders, E. M. M., and Cook, P. R. (1998) Numbers and organization of RNA polymerases, nascent transcripts, and transcription units in HeLa nuclei. Mol. Biol. Cell 9, 1523–1536 [36] Pombo, A., Jackson D. A, Hollinshead, M., Wang, Z., Roeder, R. G., and Cook, P. R. (1999) Regional specialization in human nuclei: visualization of discrete sites of transcription by RNA polymerase III. EMBO J. 18, 2241–2253PubMed ID9614191, 10205177
Method "Most of the problems can be minimized if cells are simply permeabilized using mild detergents, washed to remove endogenous pools, and transcription performed under conditions that mimic those found in vivo (primary source 20). This preserves active polymerase complexes and allows the number of active polymerases/cell to be determined, providing the number of nucleotides incorporated into each RNA can be established."
Comments "In HeLa cells, this approach [see measurement method] gives ~90,000 nascent RNA chains per cell, with ~15,000 active pol I and 75,000 active pol II/III complexes, ~10% of which are pol III (primary Sources)."
Entered by Uri M
ID 111166