A Kinetic Framework for a Mammalian RNA Polymerase in Vivo

+ See all authors and affiliations

Science  22 Nov 2002:
Vol. 298, Issue 5598, pp. 1623-1626
DOI: 10.1126/science.1076164

You are currently viewing the abstract.

View Full Text


We have analyzed the kinetics of assembly and elongation of the mammalian RNA polymerase I complex on endogenous ribosomal genes in the nuclei of living cells with the use of in vivo microscopy. We show that components of the RNA polymerase I machinery are brought to ribosomal genes as distinct subunits and that assembly occurs via metastable intermediates. With the use of computational modeling of imaging data, we have determined the in vivo elongation time of the polymerase, and measurements of recruitment and incorporation frequencies show that incorporation of components into the assembling polymerase is inefficient. Our data provide a kinetic and mechanistic framework for the function of a mammalian RNA polymerase in living cells.

  • * To whom correspondence should be addressed. E-mail: mistelit{at}

View Full Text

Related Content