Antisense Transcripts Impede Uridylation-induced Exonucleolytic Degradation to Generate Guide RNAs

ABSTRACT: Small non-coding RNA biogenesis typically involves cleavage of structured precursors by RNase III-like endonucleases. However, guide RNAs that direct U-insertion/deletion mRNA editing in mitochondria of trypanosomes maintain 5′ triphosphate characteristic of transcription start site and possess U-tail indicative of 3′ processing and uridylation. Here, we identified a protein complex composed of RET1 TUTase and 3′-5′ DSS1 exonuclease, and three additional subunits. This complex, termed mitochondrial 3′ processome (MPsome), is responsible for primary uridylation of ~800-nt gRNA precursors, their processive degradation to a mature length of 50-60 nt, and secondary U-tail addition. Both strands of gRNA gene are transcribed giving rise to sense and antisense precursors of similar size

ORGANISM(S): Trypanosoma brucei

SUBMITTER: Ruslan Afasizhev 

PROVIDER: E-GEOD-71292 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress