Uridine insertion/deletion RNA editing in Trypanosomatids: specific stimulation in vitro of Leishmania tarentolae REL1 RNA ligase activity by the MP63 zinc finger protein.
U-insertion/deletion RNA editing of mitochondrial mRNAs in trypanosome mitochondria is mediated by a core complex (RECC) containing around 16-20 proteins which is linked to several other multiprotein complexes by RNA. There are two known subcomplexes in the RECC: the REL1 subcomplex which contains the REL1 RNA ligase, the MP63 zinc finger-containing protein and the REX2 U-specific 3'-5' exonuclease; and the REL2 subcomplex which contains the REL2 RNA ligase, the RET2 3' TUTase and the MP81 zinc finger-containing protein. In this study we have affinity isolated recombinant TAP-tagged Leishmania major RET2 and Leishmania tarentolae MP63, REL1 and REL2 proteins after expression in baculovirus-infected insect cells. Recombinant MP63 protein was found to stimulate several in vitro activities of recombinant REL1; these activities include autoadenylation, bridged ligation and even pre-cleaved gRNA-mediated U-insertion editing with RET2 which is in the REL2 subcomplex. There was no effect of recombinant MP63 on similar REL2 ligation activities. The specificity for REL1 is consistent with MP63 being a component of the REL1 subcomplex. These results suggest that in vivo the interaction of MP63 with REL1 may play a role in regulating the overall activity of RNA editing.
Department of Cardiodiagnostics, 200 UCLA Medical Plaza, Suite 330, Los Angeles, CA 90095, USA.
Guanghan
G
Gao
Kestrel
K
Rogers
Feng
F
Li
Qiang
Q
Guo
Daren
D
Osato
Sharleen X
SX
Zhou
Arnold M
AM
Falick
Larry
L
Simpson
D000818:Animals; D016367:Baculoviridae; D019729:Carbon-Oxygen Ligases / Q000378:metabolism*; D005822:Genetic Vectors; D007891:Leishmania / Q000201:enzymology / Q000378:metabolism*; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism*; D008954:Models, Biological; D008956:Models, Chemical; D025941:Protein Interaction Mapping; D020836:Protein Structure, Quaternary; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D017393:RNA Editing; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D014529:Uridine / Q000378:metabolism*; D016335:Zinc Fingers
D015800:Protozoan Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D019729:Carbon-Oxygen Ligases; D014529:Uridine