title: In vitro RNA editing-like activity in a mitochondrial extract from Leishmania tarentolae.
abstract: A mitochondrial extract from Leishmania tarentolae directs the incorporation of uridylate (U) residues within the pre-edited domain of synthetic cytochrome b (CYb) and NADH dehydrogenase subunit 7 mRNA. This has several characteristics of an in vitro RNA editing activity, but no direct evidence for involvement of guide RNAs was obtained. Inhibition by micrococcal nuclease suggests a requirement for some type of endogenous RNA. The limitation of internal U-incorporation to the pre-edited region in the CYb mRNA and the inhibition by deletion or substitution of both mRNA anchor sequences for CYb gRNA-I and -II could be consistent either with a gRNA-mediated process or a secondary structure-mediated process. A low level of incorporation of [alpha-32P]CTP occurs at the same sites as UTP. Internal U-incorporation activity is selectively inhibited by heterologous RNAs, suggesting an involvement of low affinity RNA-binding proteins which can be competed by the added RNA.
authors: Department of Biology, University of California, Los Angeles 90024.
authors: G C
authors: GC
authors: Frech
authors: N
authors: N
authors: Bakalara
authors: L
authors: L
authors: Simpson
authors: A M
authors: AM
authors: Simpson
mesh_terms: D000818:Animals; D001483:Base Sequence; D002474:Cell-Free System; D003570:Cytidine Triphosphate / Q000378:metabolism; D003573:Cytochrome b Group / Q000235:genetics; D003839:Deoxyadenosines / Q000378:metabolism; D007891:Leishmania / Q000235:genetics* / Q000378:metabolism; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009245:NADH Dehydrogenase / Q000235:genetics; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis; D011062:Polynucleotide Adenylyltransferase / Q000378:metabolism; D017393:RNA Editing / Q000235:genetics*; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016914:Ribonuclease H / Q000378:metabolism; D013379:Substrate Specificity; D014544:Uridine Triphosphate / Q000378:metabolism
chemical_list: D003573:Cytochrome b Group; D003839:Deoxyadenosines; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D003570:Cytidine Triphosphate; D009245:NADH Dehydrogenase; D011062:Polynucleotide Adenylyltransferase; D016914:Ribonuclease H; C058120:cordycepin; D014544:Uridine Triphosphate