RNA editing: a mechanism for gRNA-specified uridylate insertion into precursor mRNA.
In the mitochondria of trypanosomatid protozoa the precursors of messenger RNAs (pre-mRNAs) have their coding information remodeled by the site-specific insertion and deletion of uridylate (U) residues. Small trans-acting guide RNAs (gRNAs) supply the genetic information for this RNA editing. An in vitro system was developed to study the mechanism of U insertion into pre-mRNA. U-insertion editing occurs through a series of enzymatic steps that begin with gRNA-directed pre-mRNA cleavage. Inserted U's are derived from free uridine triphosphate and are added to the 3' terminus of a 5' pre-mRNA cleavage product. gRNA specifies edited RNA sequence at the subsequent ligation step by base pairing-mediated juxtaposition of the 3' cleavage product and the processed 5' cleavage product. gRNA/pre-mRNA chimeras, purported intermediates, seem to be abortive end products of the same reaction.
Kable
M L
ML
Seattle Biomedical Research Institute, Seattle, WA 98109, USA.
Seiwert
S D
SD
Heidmann
S
S
Stuart
K
K
D000818:Animals; D001483:Base Sequence; D016831:Crithidia fasciculata / Q000235:genetics / Q000378:metabolism; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D008957:Models, Genetic; D008969:Molecular Sequence Data; D012313:RNA / Q000378:metabolism; D017393:RNA Editing; D012322:RNA Precursors / Q000378:metabolism*; D017394:RNA, Guide, Kinetoplastida / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D000077278:RNA, Mitochondrial; D016053:RNA, Protozoan / Q000378:metabolism; D014346:Trypanosoma brucei brucei / Q000235:genetics / Q000378:metabolism; D014351:Trypanosomatina / Q000235:genetics* / Q000378:metabolism; D014542:Uridine Monophosphate / Q000378:metabolism*; D014544:Uridine Triphosphate / Q000378:metabolism
D012322:RNA Precursors; D012333:RNA, Messenger; D000077278:RNA, Mitochondrial; D016053:RNA, Protozoan; D012313:RNA; D014542:Uridine Monophosphate; D014544:Uridine Triphosphate; D017394:RNA, Guide, Kinetoplastida