1 / 10

RRF-1

RRF-1. Ruchira Ranaweera. Clone summary. What is the function of “rrf-1”?. RNA-directed RNA Polymerase Amplifies RNAi silencing Only required for RNAi in somatic cells, NOT germline. What is an RNA-directed RNA Polymerase?. Different from RNA polymerase used in transcription

beryl
Download Presentation

RRF-1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. RRF-1 Ruchira Ranaweera

  2. Clone summary

  3. What is the function of “rrf-1”? • RNA-directed RNA Polymerase • Amplifies RNAi silencing • Only required for RNAi in somatic cells, NOT germline

  4. What is an RNA-directed RNA Polymerase? • Different from RNA polymerase used in transcription • RdRp uses RNA as a template to create an RNA copy, or a cRNA • Involved in RNAi amplification causing transitive RNA interference

  5. Blast-n search results • Shows 78% sequence similarity in C. elegans cosmid F26A3 • Best matching ORF was rrf-1 coding region • Chromosome I , +2.23 • exons 12 and 13 • Related gene ego-1, also an RdRP is downstream of rrf-1 in genome

  6. Protein Homology • Putative Conserved RdRp domain found • Extensive homology in nematodes (C. remanei vs. C. elegans, C. briggsae) • Also homologous to other RdRp in plant species (Arabidopsis thaliana, Oryza Sativa)

  7. Protein Sequence Alignment • Highly conserved sequence matches with other RdRp homologs in C. elegans • Conserved across region with RdRp domain

  8. RNA interference • RdRp amplifies siRNA-directed silencing • Produces more copies of long dsRNA using trigger siRNA as a primer which can then be cleaved by Dicer • The new siRNAs have unique specificities • Amplified response allows for degradation of a large amount of dsRNA www.pnas.orgcgidoi10.1073pnas.1232238100 Dillin, A. “The specifics of small interfering RNA specificity”

  9. Why have RNAi? • First line of defense against viruses and transposons • RdRp helps send immune response signal to other cells in organism • Propagates a good adaptive immunity • Vertebrates may have evolved past need for RdRp

  10. Future of RdRp and RNAi • Mutants of rrf-1 • Study selective silencing of genes in germline • Research • Study gene expression and regulation without need for complete gene knockouts • RNAi therapy • Treat genetic diseases where genes have been incorrectly activated

More Related