Questions, Feedback & Help
Send us an email and we'll get back to you ASAP. Or you can read our Frequently Asked Questions.
  • page settings
  • hide sidebar
  • show empty fields
  • layout
  • (too narrow)
  • open all
  • close all
Resources » Paper

Craig P Hunter et al. (2003) International Worm Meeting "Genetic and biochemical analysis of systemic RNAi."

  • History

  • Referenced

  • Tree Display

  • My Favorites

  • My Library

  • Comments on Craig P Hunter et al. (2003) International Worm Meeting "Genetic and biochemical analysis of systemic RNAi." (0)

  • Overview

    Status:
    Publication type:
    Meeting_abstract
    WormBase ID:
    WBPaper00019033

    Craig P Hunter, William Winston, Marie Sutherlin, Evan Feinberg, Christina Molodowitch, & Frances Chu (2003). Genetic and biochemical analysis of systemic RNAi presented in International Worm Meeting. Unpublished information; cite only with author permission.

    RNAi in C. elegans, whether induced by ingestion or injection of double-stranded RNA (dsRNA), spreads throughout the organism and is transmitted to the progeny. We are investigating how gene-specific RNAi silencing information, most likely dsRNA, is transmitted between cells. Our initial genetic screen isolated over 200 mutants in at least five SID genes (Systemic RNAi Defective). We have identified two of these, SID-1 and SID-2, whose structure, subcellular localization, and expression pattern have been informative for how double-stranded RNA may be transported into and between cells (Science 295: 2456 and in preparation). sid-1 is required for spreading of RNAi between and within all tested cells and tissues. sid-1 encodes a protein with 11 predicted transmembrane domains and a large extracellular domain, suggesting that it may function as a channel for transport of dsRNA into cells. Experimental analysis is consistent with this hypothesis. By mosaic analysis and RNAi in cultured embryonic cells, sid-1 is required cell autonomously for uptake of silencing information. Furthermore, functional analysis of SID-1 expressed in Drosophila S2 cells shows that it is sufficient to mediate uptake of silencing information from the culture media (see abstract by Feinberg & Hunter). Proteins homologous to SID-1 are present in mouse and human, and the prevalence of these homologs in mouse and human EST collections suggest that they are widely expressed, but it is still to be determined whether these homologous proteins can transport dsRNA or whether RNAi is systemic in mammals. sid-2, unlike sid-1, is required for ingestion (or soaking) mediated RNAi only. SID-2 is a novel transmembrane protein expressed strongly in the intestine and localized to the apical membrane, lining the lumen. This suggests that sid-2 may function as a receptor for import of dsRNA. Interestingly, SID-2::GFP expression levels respond to environmental conditions, and tests are in progress to determine whether this correlates with sensitivity to feeding or soaking RNAi.


    Tip: Seeing your name marked red? Please help us identify you.