Any process that stops, prevents, or reduces the frequency, rate or extent of transcription mediated by RNA polymerase II.

The synthesis of RNA from a DNA template by RNA polymerase I (RNAP I), originating at an RNAP I promoter.

The process in which the synthesis of an RNA molecule by RNA polymerase I using a DNA template is completed. RNAP I termination requires binding of a terminator protein so specific sequences downstream of the transcription unit.

The synthesis of the large ribosomal RNA (rRNA) transcript which encodes several rRNAs, e.g. in mammals 28S, 18S and 5.8S, from a nuclear DNA template transcribed by RNA polymerase I.

RNA polymerase I, one of three nuclear DNA-directed RNA polymerases found in all eukaryotes, is a multisubunit complex; typically it produces rRNAs. Two large subunits comprise the most conserved portion including the catalytic site and share similarity with other eukaryotic and bacterial multisubunit RNA polymerases. The remainder of the complex is composed of smaller subunits (generally ten or more), some of which are also found in RNA polymerase III and others of which are also found in RNA polymerases II and III. Although the core is competent to mediate ribonucleic acid synthesis, it requires additional factors to select the appropriate template.