Identification of Hammerhead Ribozymes in All Domains of Life Reveals Novel Structural Variations
Figure 7
Two conserved human hammerhead ribozymes.
(A) Hammerhead from human C10orf118 intron with nucleotide substitutions and insertions occurring in pig shown in green. Variations observed in other mammals are in gray. Guanosine residues depicted in lowercase were added to facilitate transcription in vitro. (B) Hammerhead from human RECK intron with nucleotide variations observed in other mammals and birds in gray. Sequence with pink background highlights identical nucleotides between C10 and RECK hammerhead sequences. Other notations are as in Figure 2. (C) Self-cleavage during transcription in vitro of RECK and C10orf118 hammerhead ribozyme sequences from human and pig. The pig and human RECK hammerhead ribozymes are identical. Expected nucleotide lengths of RNA precursors and 5′ cleavage products are shown. First and last five nucleotides of RECK in (B) are depicted to illustrate boundaries of conservation, but are not part of the transcript. (D) and (E) Genetic contexts of the human hammerheads. Untranslated region (UTR) is colored in gray and coding sequence (CDS) in blue. Gene organization is not to scale, size of hammerhead-containing introns is according to NCBI annotation (build 37).