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The assumption is that nERII binding to subunits of RNA polymerase I, followed by nERII mediated tyrosine phosphorylation of those subunits results in the dissociation of the subunits from the enzyme along with the rRNA, remaining bound to nERII. The rRNAnERII-RNA polymerase I subunit complex is shown here as forming an integral part of the 40S subunit of the ribosome.

I wish to speculate here that the subunits dissociated form the RNA polymerases following phosphorylation by nERII could continue their association with nERII and find their involvement in splicing reactions, nucleocytoplasmic transport of RNA and eventually, in translation. If this assumption is correct, future studies on ribosomal subunits should be able to confirm the presence of RNA polymerase I and III subunits in 40S ribosomes. It should also be possible to confirm whether the RNA polymerase II subunits are present in spliceosomes.
