FIG 7.

Dbp4 is required for SSU processome formation. (A) Electron micrographs of rRNA genes from the GAL::DBP4-HA strain. Examples of genes from 0 h (nondepleted) and from 5-h, 6-h, and 12-h depletions are displayed. Small arrows indicate SSU processomes, and large arrows indicate transcripts that have been cotranscriptionally cleaved. (B) Interpretive line tracings of the genes. (C) Maps of the genes with the following features highlighted: 5′ external transcribed spacer particles (small and light gray), SSU processomes (larger and black), and LSU particles beginning to form on the control gene only, i.e., transcripts 62, 68, and 71 (small and light gray with a black center) (16).