Figure 1.

Assembly map of 50S ribosomal subunit with all nonuniversal protein omitted. The map was derived from Nierhaus (2001) and is a slightly modified version of that presented previously Fox and Naik (2004). Each protein is indicated by a numbered box with the 23S rRNA indicated at the top. Lines with arrows indicate order in assembly with darker lines representing stronger dependencies. Thus L4 and L24 bind directly to the RNA and work together to facilitate the incorporation of L22. Boxes are colored with regard to the similarity of their position in assembly. For example, yellow indicates terminal proteins, which are not required for addition of any other universal protein.