title: Base-pairing in conserved 3' end of 18 S rRNA as determined by psoralen photoreaction and RNase sensitivity.
abstract: Wheat and rabbit 18 rRNAs radiolabeled at the 3' end with [5'-32P]pCp were analyzed by polyacrylamide gel electrophoresis after chemical cleavage or partial enzymatic digestion under nondenaturing conditions. rRNA was similarly analyzed after photoreaction with 4'-aminomethyl-4,5',8-trimethylpsoralen and photoreversal of the resulting pyrimidine cross-links. The digestion patterns indicated the presence of a base-paired structure within a conserved 3'-terminal sequence. This structure corresponds to the 3'-proximal hairpin configuration suggested previously for the small subunit rRNAs of Escherichia coli, yeast, rat, and silkworm on the basis of their nucleotide sequences.
mesh_terms: D000818:Animals; D001482:Base Composition; D001483:Base Sequence; D011564:Furocoumarins / Q000031:analogs & derivatives; D009690:Nucleic Acid Conformation; D010944:Plants / Q000032:analysis; D012335:RNA, Ribosomal / Q000097:blood; D011817:Rabbits; D012156:Reticulocytes / Q000032:analysis; D012260:Ribonucleases; D014307:Trioxsalen / Q000031:analogs & derivatives; D014908:Triticum / Q000032:analysis
chemical_list: D011564:Furocoumarins; D012335:RNA, Ribosomal; C018822:aminomethyltrioxsalen; D012260:Ribonucleases; D014307:Trioxsalen