Editing Caenorhabditis elegans (section)

=== RNA interference and gene silencing ===
[[File:C elegans stained.jpg|thumb|right|Wild-type ''C. elegans'' hermaphrodite stained with the fluorescent dye [[Texas Red]] to highlight the nuclei of all cells]]

[[RNA interference]] (RNAi) is a relatively straightforward method of disrupting the function of specific genes. [[Gene silencing|Silencing]] the function of a gene can sometimes allow a researcher to infer its possible function. The nematode can be soaked in, injected with,<ref>{{Cite web|url=https://www.youtube.com/watch?v=Wam-kw4xwZc| archive-url=https://ghostarchive.org/varchive/youtube/20211117/Wam-kw4xwZc| archive-date=2021-11-17 | url-status=live|title=Injection of C. elegans Gonads|last=NIDDK|first=National Institute of Diabetes and Digestive and Kidney Diseases|website=YouTube|date=March 5, 2015|access-date=March 21, 2020}}{{cbignore}}</ref> or fed with genetically [[Transformation (genetics)|transformed]] bacteria that [[gene expression|express]] the double-stranded RNA of interest, the sequence of which complements the sequence of the gene that the researcher wishes to disable.<ref>
{{cite journal | vauthors = Kamath RS, Fraser AG, Dong Y, Poulin G, Durbin R, Gotta M, Kanapin A, Le Bot N, Moreno S, Sohrmann M, Welchman DP, Zipperlen P, Ahringer J | title = Systematic functional analysis of the Caenorhabditis elegans genome using RNAi | journal = Nature | volume = 421 | issue = 6920 | pages = 231–7 | date = January 2003 | pmid = 12529635 | doi = 10.1038/nature01278 | bibcode = 2003Natur.421..231K | hdl = 10261/63159 | s2cid = 15745225 }}</ref>
RNAi has emerged as a powerful tool in the study of functional genomics. ''C. elegans'' has been used to analyse gene functions and claim the promise of future findings in the systematic genetic interactions.<ref>{{cite journal | vauthors = Fortunato A, Fraser AG | title = Uncover genetic interactions in Caenorhabditis elegans by RNA interference | journal = Bioscience Reports | volume = 25 | issue = 5–6 | pages = 299–307 | date = 2005 | pmid = 16307378 | doi = 10.1007/s10540-005-2892-7 | s2cid = 6983519  }}</ref>

Environmental RNAi uptake is much worse in other species of worms in the genus ''Caenorhabditis''. Although injecting RNA into the body cavity of the animal induces [[gene silencing]] in most species, only ''C. elegans'' and a few other distantly related nematodes can take up RNA from the bacteria they eat for RNAi.<ref>
{{cite journal | vauthors = Félix MA | title = RNA interference in nematodes and the chance that favored Sydney Brenner | journal = Journal of Biology | volume = 7 | issue = 9 | pages = 34 | date = November 2008 | pmid = 19014674 | pmc = 2776389 | doi = 10.1186/jbiol97 | doi-access = free }}</ref> This ability has been mapped down to a single gene, ''sid-2'', which, when inserted as a [[transgene]] in other species, allows them to take up RNA for RNAi as ''C. elegans'' does.<ref>
{{cite journal | vauthors = Winston WM, Sutherlin M, Wright AJ, Feinberg EH, Hunter CP | title = Caenorhabditis elegans SID-2 is required for environmental RNA interference | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 104 | issue = 25 | pages = 10565–70 | date = June 2007 | pmid = 17563372 | pmc = 1965553 | doi = 10.1073/pnas.0611282104 | bibcode = 2007PNAS..10410565W | doi-access = free }}</ref>