title: Evidence for RNA-RNA cross-link formation in Escherichia coli ribosomes.
abstract: Evidence is presented in three separate cases for the formation of RNA-RNA cross-links in intact E. coli ribosomes and ribosomal subunits. The first case is a cross-link between the 18S and 13S regions of the 23S RNA, induced by ultraviolet irradiation. The second is a cross-link at the subunit interface, generated by the bifunctional reagent bis-(2-chloroethyl)-amine. The third example is a cross-link between sections O'-D and P-A of the 16S RNA, induced as in the first case by ultraviolet irradiation. The RNA-RNA cross-links can be identified as such, despite the complications introduced by concomitant RNA-protein cross-linking reactions. The experiments represent a first attempt to introduce RNA-RNA cross-linking into studies of the topographical organization of the RNA within the ribosome.
mesh_terms: D004926:Escherichia coli / Q000648:ultrastructure; D008466:Mechlorethamine; D008970:Molecular Weight; D012335:RNA, Ribosomal / Q000528:radiation effects; D012270:Ribosomes / Q000648:ultrastructure*; D014466:Ultraviolet Rays
chemical_list: D012335:RNA, Ribosomal; D008466:Mechlorethamine