Difference between revisions of "What is a C. elegans?"
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− | <p><em><strong>Caenorhabditis elegans</strong></em> (pronounced <span title="Pronunciation in the International Phonetic Alphabet (IPA) | + | <p><font color="#000000"><em><strong>Caenorhabditis elegans</strong></em> (pronounced <span class="IPA" title="Pronunciation in the International Phonetic Alphabet (IPA)">/ˌsiːnoʊræbˈdaɪt<s>ɪ</s>s ˈɛl<s>ɪ</s>gænz/</span>) is a free-living, transparent nematode (roundworm), about 1 mm in length, which lives in temperate soil environments. Research into the molecular and developmental biology of <em>C. elegans</em> was begun in 1974 by Sydney Brenner and it has since been used extensively as a model organism.<sup class="reference" id="cite_ref-0"><span>[</span>1<span>]</span></sup></font></p> |
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− | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Biology</font></span></h2> | |
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− | <div style=" | + | <div class="thumbinner" style="WIDTH: 182px"><font color="#000000"><img class="thumbimage" height="95" alt="" width="180" border="0" src="http://upload.wikimedia.org/wikipedia/commons/b/be/CrawlingCelegans.gif" /> </font> |
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− | Movement of | + | <font color="#000000">Movement of Wild-type <em>C. elegans</em></font></div> |
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− | <p><em>C. elegans</em> is | + | <p><font color="#000000"><em>C. elegans</em> is unsegmented, vermiform, bilaterally symmetrical, with a cuticle integument, four main epidermal cords and a fluid-filled pseudocoelomate cavity. Members of the species have many of the same organ systems as other animals. In the wild, they feed on bacteria that develop on decaying vegetable matter. Individuals of <em>C. elegans</em> are almost all hermaphrodite, with males comprising just 0.05% of the total population on average. The basic anatomy of <em>C. elegans</em> includes a mouth, pharynx, intestine, gonad, and collagenous cuticle. Males have a single-lobed gonad, vas deferens, and a tail specialized for mating. Hermaphrodites have two ovaries, oviducts, spermatheca, and a single uterus.</font></p> |
− | <p><em>C. elegans</em> eggs are laid by the hermaphrodite. After hatching, they | + | <p><font color="#000000"><em>C. elegans</em> eggs are laid by the hermaphrodite. After hatching, they pass through four larval stages (L1-L4). When crowded or in the absence of food, <em>C. elegans</em> can enter an alternative third larval stage called the dauer state. Dauer larvae are stress-resistant and do not age. Hermaphrodites produce all their sperm in the L4 stage (150 sperm per gonadal arm) and then switch over to producing oocytes. The sperm are stored in the same area of the gonad as the oocytes until the first oocyte pushes the sperm into the spermatheca (a kind of chamber where the oocytes become fertilized by the sperm).<sup class="reference" id="cite_ref-1"><span>[</span>2<span>]</span></sup> The male can inseminate the hermaphrodite, which will use male sperm preferentially (both types of sperm are stored in the spermatheca). When self-inseminated the wild-type worm will lay approximately 300 eggs. When inseminated by a male, the number of progeny can exceed 1,000. At 20°C, the laboratory strain of <em>C. elegans</em> has an average life span of approximately 2–3 weeks and a generation time of approximately 4 days. Hermaphrodites can mate with males or self-fertilize.</font></p> |
− | <p><em>C. elegans</em> has five pairs of | + | <p><font color="#000000"><em>C. elegans</em> has five pairs of autosomes and one pair of sex chromosomes. Sex in <em>C. elegans</em> is based on an X0 sex-determination system. Hermaphrodite <em>C. elegans</em> have a matched pair of sex chromosomes (XX); the rare males have only one sex chromosome (X0).</font></p> |
− | <p>It is interesting to note that <em>C. elegans</em> is one of the only forms of | + | <p><font color="#000000">It is interesting to note that <em>C. elegans</em> is one of the only forms of life not known to have a natural virus.<sup class="reference" id="cite_ref-2"><span>[</span>3<span>]</span></sup></font></p> |
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− | <div style=" | + | <div class="thumbinner" style="WIDTH: 502px"><font color="#000000"><img class="thumbimage" height="94" alt="" width="500" border="0" src="http://upload.wikimedia.org/wikipedia/commons/thumb/8/88/C_elegans_anatomy.png/500px-C_elegans_anatomy.png" /> </font> |
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− | Longitudinal | + | <font color="#000000">Longitudinal section through the hermaphrodite <em>C. elegans.</em></font></div> |
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− | <p>< | + | <p><font color="#000000"></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">Laboratory uses</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000">Laboratory uses</font></span></h2> |
− | <p><em>C. elegans</em> is studied as a | + | <p><font color="#000000"><em>C. elegans</em> is studied as a model organism for a variety of reasons. Strains are cheap to breed and can be frozen. When subsequently thawed they remain viable, allowing long-term storage. Because the complete cell lineage of the species has been determined, <em>C. elegans</em> has proven especially useful for studying cellular differentiation.</font></p> |
− | <p>From a research perspective, <em>C. elegans</em> has the advantage of being a | + | <p><font color="#000000">From a research perspective, <em>C. elegans</em> has the advantage of being a multicellular eukaryotic organism that is simple enough to be studied in great detail. In addition, it is transparent facilitating the study of developmental processes in the intact organism. The developmental fate of every single somatic cell (959 in the adult hermaphrodite; 1031 in the adult male) has been mapped out. These patterns of cell lineage are largely invariant between individuals, in contrast to mammals where cell development from the embryo is more largely dependent on cellular cues. In both sexes, a large number of additional cells (131 in the hermaphrodite, most of which would otherwise become neurons), are eliminated by programmed cell death (apoptosis).</font></p> |
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− | <div style=" | + | <div class="thumbinner" style="WIDTH: 252px"><font color="#000000"><img class="thumbimage" height="345" alt="" width="250" border="0" src="http://upload.wikimedia.org/wikipedia/commons/thumb/7/77/C_elegans_stained.jpg/250px-C_elegans_stained.jpg" /> </font> |
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− | <div class="magnify">< | + | <div class="magnify"><font color="#000000"><img height="11" alt="" width="15" src="/skins-1.5/common/images/magnify-clip.png" /></font></div> |
− | Wild-type | + | <font color="#000000">Wild-type <em>C. elegans</em> hermaphrodite stained to highlight the nuclei of all cells</font></div> |
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− | <p>In addition, <em>C. elegans</em> is one of the simplest organisms with a | + | <p><font color="#000000">In addition, <em>C. elegans</em> is one of the simplest organisms with a nervous system. In the hermaphrodite, this comprises 302 neurons whose pattern of connectivity has been completely mapped out, and shown to be a small-world network.<sup class="reference" id="cite_ref-3"><span>[</span>4<span>]</span></sup> Research has explored the neural mechanisms responsible for several of the more interesting behaviors shown by <em>C. elegans</em>, including chemotaxis, thermotaxis, mechanotransduction, and male mating behavior.</font></p> |
− | + | <p><font color="#000000">A useful feature of <em>C. elegans</em> is that it is relatively straightforward to disrupt the function of specific genes by RNA interference (RNAi). Silencing the function of a gene in this way can sometimes allow a researcher to infer what the function of that gene may be. The nematode can either be soaked in (or injected with) a solution of double stranded RNA, the sequence of which is complementary to the sequence of the gene that the researcher wishes to disable. Alternatively, worms can be fed on genetically transformed bacteria which express the double stranded RNA of interest.</font></p> | |
− | + | <p><font color="#000000"><em>C. elegans</em> has also been useful in the study of meiosis. As sperm and egg nuclei move down the length of the gonad, they undergo a temporal progression through meiotic events. This progression means that every nucleus at a given position in the gonad will be at roughly the same step in meiosis, eliminating the difficulties of heterogeneous populations of cells.</font></p> | |
− | <p>The organism has also been identified as a model for | + | <p><font color="#000000">The organism has also been identified as a model for nicotine dependence as it has been found to experience the same symptoms humans experience when they quit smoking.<sup class="reference" id="cite_ref-4"><span>[</span>5<span>]</span></sup></font></p> |
− | <p>As for most model organisms, there is a dedicated online database for the | + | <p><font color="#000000">As for most model organisms, there is a dedicated online database for the species that is actively curated by scientists working in this field. The WormBase database attempts to collate all published information on <em>C. elegans</em> and other related nematodes. A reward of $5000 has been advertised on their website, for the finder of a new species of closely related nematode.<sup class="reference" id="cite_ref-5"><span>[</span>6<span>]</span></sup> Such a discovery would broaden research opportunities with the worm.<sup class="reference" id="cite_ref-6"><span>[</span>7<span>]</span></sup></font></p> |
− | <p>< | + | <p><font color="#000000"></font></p> |
− | <h2><span class=" | + | <h2><span class="mw-headline"><font color="#000000">C. elegans Genome</font></span></h2> |
− | <p>< | + | <p><font color="#000000"><em>C. elegans</em> was the first multicellular organism to have its genome completely sequenced. The finished genome sequence was published in 1998,<sup class="reference" id="cite_ref-7"><span>[</span>8<span>]</span></sup> although a number of small gaps were present (the last gap was finished by October 2002). The <em>C. elegans</em> genome sequence is approximately 100 million base pairs long and contains approximately 20,000 genes. The vast majority of these genes encode for proteins but there are likely to be as many as 1,000 RNA genes. Scientific curators continue to appraise the set of known genes, such that new gene predictions continue to be added and incorrect ones modified or removed.</font></p> |
− | <p>In 2003, the genome sequence of the related nematode <em>< | + | <p><font color="#000000">In 2003, the genome sequence of the related nematode <em>C. briggsae</em> was also determined, allowing researchers to study the comparative genomics of these two organisms.<sup class="reference" id="cite_ref-8"><span>[</span>9<span>]</span></sup> Work is now ongoing to determine the genome sequences of more nematodes from the same genus such as <em>C. remanei</em>,<sup class="reference" id="cite_ref-9"><span>[</span>10<span>]</span></sup> <em>C. japonica</em><sup class="reference" id="cite_ref-10"><span>[</span>11<span>]</span></sup> and <em>C. brenneri</em>.<sup class="reference" id="cite_ref-11"><span>[</span>12<span>]</span></sup> These newer genome sequences are being determined by using the whole genome shotgun technique which means that the resulting genome sequences are likely to not be as complete or accurate as <em>C. elegans</em> (which was sequenced using the 'hierarchical' or clone-by-clone approach).</font></p> |
− | <p> | + | <p><font color="#000000">The official version of the <em>C. elegans</em> genome sequence continues to change as and when new evidence reveals errors in the original sequencing (DNA sequencing is not an error-free process). Most changes are minor, adding or removing only a few base pairs (bp) of DNA. E.g. the WS169 release of WormBase (December 2006) lists a net gain of 6 bp to the genome sequence.<sup class="reference" id="cite_ref-WS169_12-0"><span>[</span>13<span>]</span></sup> Occasionally more extensive changes are made, e.g. the WS159 release of May 2006 added over 300 bp to the sequence.<sup class="reference" id="cite_ref-WS159_13-0"><span>[</span>14<span>]</span></sup></font></p> |
− | <p><a | + | <p><font color="#000000"><a id="Evolution" name="Evolution"></a></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline"> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Evolution</font></span></h2> |
− | <p>It has been shown that a small number of conserved < | + | <p><font color="#000000">It has been shown that a small number of conserved protein sequences from sponges are more similar to humans than to <em>C. elegans</em>.<sup class="reference" id="cite_ref-14"><span>[</span>15<span>]</span></sup> This suggests that there has been an accelerated rate of evolution in the <em>C. elegans</em> lineage. The same study found that several phylogenetically ancient genes are not present in <em>C. elegans</em>.</font></p> |
− | + | <p><font color="#000000"><a id="Scientific_community" name="Scientific_community"></a></font></p> | |
− | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Scientific community</font></span></h2> | |
− | < | + | <p><font color="#000000">In 2002, the Nobel Prize in Physiology or Medicine was awarded to Sydney Brenner, H. Robert Horvitz and John Sulston for their work on the genetics of organ development and programmed cell death (PCD) in <em>C. elegans</em>. The 2006 Nobel Prize in Physiology or Medicine was awarded to Andrew Fire and Craig C. Mello, for their discovery of RNA interference in <em>C. elegans</em>.<sup class="reference" id="cite_ref-15"><span>[</span>16<span>]</span></sup>. In 2008 Martin Chalfie shared a Nobel Prize in Chemistry for his work on green fluorescent protein (GFP) in <em>C. elegans</em>.</font></p> |
− | + | <p><font color="#000000">Because all research into <em>C. elegans</em> essentially started with Sydney Brenner in the 1970s, many scientists working in this field share a close connection to Brenner (they either worked as a post-doctoral or post-graduate researcher in Brenner's lab or in the lab of someone who previously worked with Brenner). Because most people who worked in his lab went on to establish their own worm research labs, there is now a fairly well documented 'lineage' of <em>C. elegans</em> scientists. This lineage was recorded in some detail at the 2003 International Worm Meeting and the results were stored in the Wormbase database.</font></p> | |
− | + | <p><font color="#000000"><a id="In_the_media" name="In_the_media"></a></font></p> | |
− | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>In the media</font></span></h2> | |
− | + | <p><font color="#000000"><em>C. elegans</em> made news when it was discovered that specimens had survived the Space Shuttle <em>Columbia</em> disaster in February 2003.<sup class="reference" id="cite_ref-16"><span>[</span>17<span>]</span></sup> Later, in January 2009, it was announced that live samples of C.elegans from the University of Nottingham will spend two weeks on the International Space Station as part of a project to explore the effects of zero gravity on muscle development and its physiology. The emphasis of the research will be on the genetic basis of muscle atrophy. This has relevance to space travel, but also to individuals who are bed-ridden, geriatric or diabetic.<sup class="reference" id="cite_ref-17"><span>[</span>18<span>]</span></sup></font></p> | |
− | + | <p><font color="#000000"><a id="See_also" name="See_also"></a></font></p> | |
− | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000">See also about <span class="mw-headline"><font color="#000000">C. elegans </font></span></font></span></h2> | |
<ul> | <ul> | ||
− | <li>< | + | <li><font color="#000000">Animal testing on invertebrates </font></li> |
</ul> | </ul> | ||
− | <p><a | + | <p><font color="#000000"><a id="References" name="References"></a></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">References</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>References</font></span></h2> |
<div class="references-small"> | <div class="references-small"> | ||
<ol class="references"> | <ol class="references"> | ||
− | <li id="cite_note-0">< | + | <li id="cite_note-0"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFBrenner.2C_S.1974" style="FONT-STYLE: normal">Brenner, S. (May 1974). "The Genetics of <em>Caenorhabditis elegans</em>" (PDF). <em>Genetics</em> <strong>77</strong>: 71–94<span class="printonly">. http://dev.wormbase.org/papers/31_Brenner74.pdf</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=The+Genetics+of+%27%27Caenorhabditis+elegans%27%27&rft.jtitle=%5B%5BGenetics+%28journal%29%7CGenetics%5D%5D&rft.aulast=Brenner%2C+S.&rft.au=Brenner%2C+S.&rft.date=May+1974&rft.volume=77&rft.pages=71%E2%80%9394&rft_id=http%3A%2F%2Fdev.wormbase.org%2Fpapers%2F31_Brenner74.pdf&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
− | + | <li id="cite_note-1"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFNayak.2C_S..2C_J._Goree_.26_T._Schedl2004" style="FONT-STYLE: normal">Nayak, S., J. Goree & T. Schedl (2004). "<em>fog-2</em> and the Evolution of Self-Fertile Hermaphroditism in <em>Caenorhabditis</em>". <em>PLoS Biology</em> <strong>3</strong> (1): e6. doi:<span class="neverexpand">10.1371/journal.pbio.0030006</span><span class="printonly">. http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030006</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=%27%27fog-2%27%27+and+the+Evolution+of+Self-Fertile+Hermaphroditism+in+%27%27Caenorhabditis%27%27&rft.jtitle=%5B%5BPLoS+Biology%5D%5D&rft.aulast=Nayak%2C+S.%2C+J.+Goree+%26+T.+Schedl&rft.au=Nayak%2C+S.%2C+J.+Goree+%26+T.+Schedl&rft.date=2004&rft.volume=3&rft.issue=1&rft.pages=e6&rft_id=info:doi/10.1371%2Fjournal.pbio.0030006&rft_id=http%3A%2F%2Fbiology.plosjournals.org%2Fperlserv%2F%3Frequest%3Dget-document%26doi%3D10.1371%2Fjournal.pbio.0030006&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | <li id="cite_note- | + | <li id="cite_note-2"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFShaham_S.2006" style="FONT-STYLE: normal">Shaham S. (March 14 2006). "Worming into the cell: Viral reproduction in Caenorhabditis elegans" (PDF). <em>Proc Natl Acad Sci USA</em> <strong>103</strong> (11): 3955–56. doi:<span class="neverexpand">10.1073/pnas.0600779103</span>. PMID 16537467<span class="printonly">. http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1449626&blobtype=pdf</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Worming+into+the+cell%3A+Viral+reproduction+in+Caenorhabditis+elegans&rft.jtitle=Proc+Natl+Acad+Sci+USA&rft.aulast=Shaham+S.&rft.au=Shaham+S.&rft.date=March+14+2006&rft.volume=103&rft.issue=11&rft.pages=3955%E2%80%9356&rft_id=info:doi/10.1073%2Fpnas.0600779103&rft_id=info:pmid/16537467&rft_id=http%3A%2F%2Fwww.pubmedcentral.nih.gov%2Fpicrender.fcgi%3Fartid%3D1449626%26blobtype%3Dpdf&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
− | + | <li id="cite_note-3"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFWatts_D._J._.26_S._H._Strogatz1998" style="FONT-STYLE: normal">Watts D. J. & S. H. Strogatz (June 1998). "Collective dynamics of 'small-world' networks". <em>Nature</em> <strong>393</strong> (6684): 440–442. doi:<span class="neverexpand">10.1038/30918</span><span class="printonly">. http://www.nature.com/nature/journal/v393/n6684/abs/393440a0.html</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Collective+dynamics+of+%27small-world%27+networks&rft.jtitle=%5B%5BNature+%28journal%29%7CNature%5D%5D&rft.aulast=Watts+D.+J.+%26+S.+H.+Strogatz&rft.au=Watts+D.+J.+%26+S.+H.+Strogatz&rft.date=June+1998&rft.volume=393&rft.issue=6684&rft.pages=440%E2%80%93442&rft_id=info:doi/10.1038%2F30918&rft_id=http%3A%2F%2Fwww.nature.com%2Fnature%2Fjournal%2Fv393%2Fn6684%2Fabs%2F393440a0.html&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | + | <li id="cite_note-4"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFFeng_et_al.2006" style="FONT-STYLE: normal">Feng et al. (November 2006). "A C. elegans Model of Nicotine-Dependent Behavior: Regulation by TRP-Family Channels". <em>Cell</em> <strong>127</strong>: 621–633. doi:<span class="neverexpand">10.1016/j.cell.2006.09.035</span>. PMID 17081982<span class="printonly">. http://www.cell.com/content/article/abstract?uid=PIIS0092867406012955</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=A+C.+elegans+Model+of+Nicotine-Dependent+Behavior%3A+Regulation+by+TRP-Family+Channels&rft.jtitle=%5B%5BCell+%28journal%29%7CCell%5D%5D&rft.aulast=Feng+et+al.&rft.au=Feng+et+al.&rft.date=November+2006&rft.volume=127&rft.pages=621%E2%80%93633&rft_id=info:doi/10.1016%2Fj.cell.2006.09.035&rft_id=info:pmid/17081982&rft_id=http%3A%2F%2Fwww.cell.com%2Fcontent%2Farticle%2Fabstract%3Fuid%3DPIIS0092867406012955&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | <li id="cite_note- | + | <li id="cite_note-5"><font color="#000000"><strong>^</strong> "<em>Caenorhabditis</em> isolation guide". WormBase. Retrieved on 2007-08-30. </font></li> |
− | <li id="cite_note- | + | <li id="cite_note-6"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFDolgin2007" style="FONT-STYLE: normal">Dolgin, Elie (August 2007). "Slime for a dime". <em>Science</em> <strong>317</strong> (5842): 1157. doi:<span class="neverexpand">10.1126/science.317.5842.1157b</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Slime+for+a+dime&rft.jtitle=%5B%5BScience+%28journal%29%7CScience%5D%5D&rft.aulast=Dolgin&rft.aufirst=Elie&rft.au=Dolgin%2C+Elie&rft.date=August+2007&rft.volume=317&rft.issue=5842&rft.pages=1157&rft_id=info:doi/10.1126%2Fscience.317.5842.1157b&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
− | <li id="cite_note- | + | <li id="cite_note-7"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFThe_.27.27C._elegans.27.27_Sequencing_Consortium1998" style="FONT-STYLE: normal">The <em>C. elegans</em> Sequencing Consortium (1998). "Genome sequence of the nematode <em>C. elegans</em>: a platform for investigating biology". <em>Science</em> <strong>282</strong>: 2012–2018. doi:<span class="neverexpand">10.1126/science.282.5396.2012</span>. PMID 9851916<span class="printonly">. http://www.sciencemag.org/cgi/content/abstract/282/5396/2012</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Genome+sequence+of+the+nematode+%27%27C.+elegans%27%27%3A+a+platform+for+investigating+biology&rft.jtitle=%5B%5BScience+%28journal%29%7CScience%5D%5D&rft.aulast=The+%27%27C.+elegans%27%27+Sequencing+Consortium&rft.au=The+%27%27C.+elegans%27%27+Sequencing+Consortium&rft.date=1998&rft.volume=282&rft.pages=2012%E2%80%932018&rft_id=info:doi/10.1126%2Fscience.282.5396.2012&rft_id=info:pmid/9851916&rft_id=http%3A%2F%2Fwww.sciencemag.org%2Fcgi%2Fcontent%2Fabstract%2F282%2F5396%2F2012&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
− | + | <li id="cite_note-8"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFStein.2C_L._D._.27.27et_al..27.272003" style="FONT-STYLE: normal">Stein, L. D. <em>et al.</em> (2003). "The Genome Sequence of <em>Caenorhabditis briggsae</em>: A Platform for Comparative Genomics". <em>PLoS Biology</em> <strong>1</strong>: 166–192. doi:<span class="neverexpand">10.1371/journal.pbio.0000045</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=The+Genome+Sequence+of+%27%27Caenorhabditis+briggsae%27%27%3A+A+Platform+for+Comparative+Genomics&rft.jtitle=%5B%5BPLoS+Biology%5D%5D&rft.aulast=Stein%2C+L.+D.+%27%27et+al.%27%27&rft.au=Stein%2C+L.+D.+%27%27et+al.%27%27&rft.date=2003&rft.volume=1&rft.pages=166%E2%80%93192&rft_id=info:doi/10.1371%2Fjournal.pbio.0000045&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | + | <li id="cite_note-9"><font color="#000000"><strong>^</strong> Genome Sequencing Center. "<em>Caenorhabditis remanei</em>: Background". Washington University School of Medicine. Retrieved on 2008-07-11. </font></li> | |
− | + | <li id="cite_note-10"><font color="#000000"><strong>^</strong> Genome Sequencing Center. "<em>Caenorhabditis japonica</em>: Background". Washington University School of Medicine. Retrieved on 2008-07-11. </font></li> | |
− | + | <li id="cite_note-11"><font color="#000000"><strong>^</strong> Genome Sequencing Center. "<em>Caenorhabditis brenneri</em>: Background". Washington University School of Medicine. Retrieved on 2008-07-11. </font></li> | |
− | + | <li id="cite_note-WS169-12"><font color="#000000"><strong>^</strong> "WormBaseWiki WS169 release notes". Wormbase. Retrieved on 2007-02-21. </font></li> | |
− | + | <li id="cite_note-WS159-13"><font color="#000000"><strong>^</strong> "WormBaseWiki WS159 release notes". Wormbase. Retrieved on 2007-01-21. </font></li> | |
− | + | <li id="cite_note-14"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFGamulin2000" style="FONT-STYLE: normal">Gamulin, V (December 2000). "Sponge proteins are more similar to those of <em>Homo sapiens</em> than to <em>Caenorhabditis elegans</em>". <em>Biological Journal of the Linnean Society</em> (Academic Press) <strong>71</strong> (4): 821–828.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Sponge+proteins+are+more+similar+to+those+of+%27%27Homo+sapiens%27%27+than+to+%27%27Caenorhabditis+elegans%27%27&rft.jtitle=Biological+Journal+of+the+Linnean+Society&rft.aulast=Gamulin&rft.aufirst=V&rft.au=Gamulin%2C+V&rft.date=December+2000&rft.volume=71&rft.issue=4&rft.pages=821%E2%80%93828&rft.pub=Academic+Press&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | + | <li id="cite_note-15"><font color="#000000"><strong>^</strong> <cite class="Journal" id="CITEREFFire_A.2C_Xu_S.2C_Montgomery_MK.2C_Kostas_SA.2C_Driver_SE.2C_Mello_CC1998" style="FONT-STYLE: normal">Fire A, Xu S, Montgomery MK, Kostas SA, Driver SE, Mello CC (February 1998). "Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans". <em>Nature</em> <strong>391</strong> (6669): 806–11. doi:<span class="neverexpand">10.1038/35888</span>. PMID 9486653.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=Potent+and+specific+genetic+interference+by+double-stranded+RNA+in+Caenorhabditis+elegans&rft.jtitle=Nature&rft.aulast=Fire+A%2C+Xu+S%2C+Montgomery+MK%2C+Kostas+SA%2C+Driver+SE%2C+Mello+CC&rft.au=Fire+A%2C+Xu+S%2C+Montgomery+MK%2C+Kostas+SA%2C+Driver+SE%2C+Mello+CC&rft.date=February+1998&rft.volume=391&rft.issue=6669&rft.pages=806%E2%80%9311&rft_id=info:doi/10.1038%2F35888&rft_id=info:pmid/9486653&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | + | <li id="cite_note-16"><font color="#000000"><strong>^</strong> "Worms survived Columbia disaster", BBC News (2003-05-01)<span class="reference-accessdate">. Retrieved on 11 July 2008</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.type=newspaperArticle&rft.subject=News&rft.title=Worms+survived+Columbia+disaster&rft.identifier=http%3A%2F%2Fnews.bbc.co.uk%2F1%2Fhi%2Fsci%2Ftech%2F2992123.stm&rft.publisher=%5B%5BBBC+News%5D%5D&rft.date=2003-05-01"><span style="DISPLAY: none"> </span></span> </font></li> | |
− | + | <li id="cite_note-17"><font color="#000000"><strong>^</strong> http://news.bbc.co.uk/1/hi/england/nottinghamshire/7835020.stm </font></li> | |
</ol> | </ol> | ||
</div> | </div> | ||
− | <p><a | + | <p><font color="#000000"><a id="Publications" name="Publications"></a></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">Publications</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Publications</font></span></h2> |
<ul> | <ul> | ||
− | <li><cite | + | <li><font color="#000000"><cite class="book" id="CITEREFBird.2C_Jean.3B_Bird.2C_Alan_C.1991" style="FONT-STYLE: normal">Bird, Jean; Bird, Alan C. (1991). <em>The structure of nematodes</em>. Boston: Academic Press. pp. 1, 69–70, 152–153, 165, 224–225. ISBN 0-12-099651-0.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+structure+of+nematodes&rft.aulast=Bird%2C+Jean%3B+Bird%2C+Alan+C.&rft.au=Bird%2C+Jean%3B+Bird%2C+Alan+C.&rft.date=1991&rft.pages=pp.%26nbsp%3B1%2C+69%E2%80%9370%2C+152%E2%80%93153%2C+165%2C+224%E2%80%93225&rft.place=Boston&rft.pub=%5B%5BAcademic+Press%5D%5D&rft.isbn=0-12-099651-0&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
</ul> | </ul> | ||
<ul> | <ul> | ||
− | <li><cite | + | <li><font color="#000000"><cite class="book" id="CITEREFHope.2C_Ian_A.1999" style="FONT-STYLE: normal">Hope, Ian A. (1999). <em>C. elegans: a practical approach</em>. Oxford [Oxfordshire]: Oxford University Press. pp. 1–6. ISBN 0-19-963738-5.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=C.+elegans%3A+a+practical+approach&rft.aulast=Hope%2C+Ian+A.&rft.au=Hope%2C+Ian+A.&rft.date=1999&rft.pages=pp.%26nbsp%3B1%E2%80%936&rft.place=Oxford+%5BOxfordshire%5D&rft.pub=%5B%5BOxford+University+Press%5D%5D&rft.isbn=0-19-963738-5&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
</ul> | </ul> | ||
<ul> | <ul> | ||
− | <li><cite | + | <li><font color="#000000"><cite class="book" id="CITEREFRiddle.2C_D.L..2C_T._Blumenthal.2C_R._J._Meyer_.26_J._R._Priess1997" style="FONT-STYLE: normal">Riddle, D.L., T. Blumenthal, R. J. Meyer & J. R. Priess (1997). <em>C. elegans <em>II</em></em>. Cold Spring Harbor Laboratory Press, New York. pp. 1–4, 679–683. ISBN 0-87969-532-3<span class="printonly">. http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=ce2</span>.</cite><span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=%27%27C.+elegans%27%27+II&rft.aulast=Riddle%2C+D.L.%2C+T.+Blumenthal%2C+R.+J.+Meyer+%26+J.+R.+Priess&rft.au=Riddle%2C+D.L.%2C+T.+Blumenthal%2C+R.+J.+Meyer+%26+J.+R.+Priess&rft.date=1997&rft.pages=pp.%26nbsp%3B1%E2%80%934%2C+679%E2%80%93683&rft.pub=Cold+Spring+Harbor+Laboratory+Press%2C+New+York&rft.isbn=0-87969-532-3&rft_id=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fbooks%2Fbv.fcgi%3Frid%3Dce2&rfr_id=info:sid/en.wikipedia.org:Caenorhabditis_elegans"><span style="DISPLAY: none"> </span></span> </font></li> |
</ul> | </ul> | ||
− | <p><a | + | <p><font color="#000000"><a id="Online_resources" name="Online_resources"></a></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">Online resources</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Online resources</font></span></h2> |
<ul> | <ul> | ||
− | <li>< | + | <li><font color="#000000">WormBase - an extensive online database covering the biology and genomics of <em>C. elegans</em> and other nematodes </font></li> |
− | <li>< | + | <li><font color="#000000">WormBook - a free online compendium of all aspects of <em>C. elegans</em> biology, including laboratory protocols </font></li> |
− | <li>< | + | <li><font color="#000000">Wormatlas - an online database for behavioral and structural anatomy of <em>C. elegans</em> </font></li> |
− | <li>< | + | <li><font color="#000000">Wellcome Trust Sanger Institute <em>C. elegans</em> page - half of the genome sequence is still maintained by this institute </font></li> |
− | <li>< | + | <li><font color="#000000">WashU Genome Sequencing Center <em>C. elegans</em> page - the institute maintaining the other half of the genome </font></li> |
− | <li>< | + | <li><font color="#000000">AceView WormGenes - another genome database for <em>C. elegans</em>, maintained at the NCBI </font></li> |
− | <li>< | + | <li><font color="#000000">TCNJ Worm Lab - Easy to follow protocols and pictures for <em>C. elegans</em> research. Made by undergrads for undergrads. </font></li> |
− | <li>< | + | <li><font color="#000000">Worm Classroom - An education portal for <em>C. elegans</em> </font></li> |
− | <li>< | + | <li><font color="#000000">Textpresso - WormBase search engine </font></li> |
− | <li>< | + | <li><font color="#000000"><em>C. elegans</em> movies - Timelapse films made by <em>C. elegans</em> researchers worldwide </font></li> |
− | <li>< | + | <li><font color="#000000"><em>C. elegans</em> II - a free online textbook. </font></li> |
− | <li>< | + | <li><font color="#000000">Silencing Genomes RNA interference (RNAi) experiments and bioinformatics in <em>C. elegans</em> for education. From the Dolan DNA Learning Center of Cold Spring Harbor Laboratory. </font></li> |
− | <li>< | + | <li><font color="#000000">C.elegans 3D model by the Ewbank Lab - Videos and photos that explain the basic anatomy of <em>C. elegans</em> </font></li> |
− | <li>< | + | <li><font color="#000000">WormTracker </font></li> |
</ul> | </ul> | ||
− | <p><a | + | <p><font color="#000000"><a id="Nobel_lectures" name="Nobel_lectures"></a></font></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">Nobel lectures</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><font color="#000000"><span class="mw-headline"><font color="#000000">C. elegans </font></span>Nobel lectures</font></span></h2> |
<ul> | <ul> | ||
− | <li>Brenner S (2002) Nature's Gift to Science. In. <a | + | <li>Brenner S (2002) Nature's Gift to Science. In. <a class="external free" title="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/brenner-lecture.pdf" rel="nofollow" href="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/brenner-lecture.pdf">http://nobelprize.org/nobel_prizes/medicine/laureates/2002/brenner-lecture.pdf</a> </li> |
− | <li>Horvitz HR (2002) Worms, Life and Death. In. <a | + | <li>Horvitz HR (2002) Worms, Life and Death. In. <a class="external free" title="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/horvitz-lecture.pdf" rel="nofollow" href="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/horvitz-lecture.pdf">http://nobelprize.org/nobel_prizes/medicine/laureates/2002/horvitz-lecture.pdf</a> </li> |
− | <li>Sulston JE (2002) The Cell Lineage and Beyond. In. <a | + | <li>Sulston JE (2002) The Cell Lineage and Beyond. In. <a class="external free" title="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/sulston-lecture.pdf" rel="nofollow" href="http://nobelprize.org/nobel_prizes/medicine/laureates/2002/sulston-lecture.pdf">http://nobelprize.org/nobel_prizes/medicine/laureates/2002/sulston-lecture.pdf</a> </li> |
</ul> | </ul> | ||
− | <p><a | + | <p><a id="External_links" name="External_links"></a></p> |
− | <h2><span class="editsection"></span><span class="mw-headline">External links</span></h2> | + | <h2><span class="editsection"></span><span class="mw-headline"><span class="mw-headline"><font color="#000000">C. elegans </font></span>External links</span></h2> |
<ul> | <ul> | ||
− | <li><a | + | <li><a class="external text" title="http://www.nytimes.com/2006/11/21/science/21find.html" rel="nofollow" href="http://www.nytimes.com/2006/11/21/science/21find.html">Nematodes With a Craving for Nicotine</a> </li> |
</ul> | </ul> |
Revision as of 04:25, 25 January 2009
Caenorhabditis elegans (pronounced /ˌsiːnoʊræbˈdaɪtɪs ˈɛlɪgænz/) is a free-living, transparent nematode (roundworm), about 1 mm in length, which lives in temperate soil environments. Research into the molecular and developmental biology of C. elegans was begun in 1974 by Sydney Brenner and it has since been used extensively as a model organism.[1]
Contents
- 1 C. elegans Biology
- 2 Laboratory uses
- 3 C. elegans Genome
- 4 C. elegans Evolution
- 5 C. elegans Scientific community
- 6 C. elegans In the media
- 7 See also about C. elegans
- 8 C. elegans References
- 9 C. elegans Publications
- 10 C. elegans Online resources
- 11 C. elegans Nobel lectures
- 12 C. elegans External links
C. elegans Biology
C. elegans is unsegmented, vermiform, bilaterally symmetrical, with a cuticle integument, four main epidermal cords and a fluid-filled pseudocoelomate cavity. Members of the species have many of the same organ systems as other animals. In the wild, they feed on bacteria that develop on decaying vegetable matter. Individuals of C. elegans are almost all hermaphrodite, with males comprising just 0.05% of the total population on average. The basic anatomy of C. elegans includes a mouth, pharynx, intestine, gonad, and collagenous cuticle. Males have a single-lobed gonad, vas deferens, and a tail specialized for mating. Hermaphrodites have two ovaries, oviducts, spermatheca, and a single uterus.
C. elegans eggs are laid by the hermaphrodite. After hatching, they pass through four larval stages (L1-L4). When crowded or in the absence of food, C. elegans can enter an alternative third larval stage called the dauer state. Dauer larvae are stress-resistant and do not age. Hermaphrodites produce all their sperm in the L4 stage (150 sperm per gonadal arm) and then switch over to producing oocytes. The sperm are stored in the same area of the gonad as the oocytes until the first oocyte pushes the sperm into the spermatheca (a kind of chamber where the oocytes become fertilized by the sperm).[2] The male can inseminate the hermaphrodite, which will use male sperm preferentially (both types of sperm are stored in the spermatheca). When self-inseminated the wild-type worm will lay approximately 300 eggs. When inseminated by a male, the number of progeny can exceed 1,000. At 20°C, the laboratory strain of C. elegans has an average life span of approximately 2–3 weeks and a generation time of approximately 4 days. Hermaphrodites can mate with males or self-fertilize.
C. elegans has five pairs of autosomes and one pair of sex chromosomes. Sex in C. elegans is based on an X0 sex-determination system. Hermaphrodite C. elegans have a matched pair of sex chromosomes (XX); the rare males have only one sex chromosome (X0).
It is interesting to note that C. elegans is one of the only forms of life not known to have a natural virus.[3]
Laboratory uses
C. elegans is studied as a model organism for a variety of reasons. Strains are cheap to breed and can be frozen. When subsequently thawed they remain viable, allowing long-term storage. Because the complete cell lineage of the species has been determined, C. elegans has proven especially useful for studying cellular differentiation.
From a research perspective, C. elegans has the advantage of being a multicellular eukaryotic organism that is simple enough to be studied in great detail. In addition, it is transparent facilitating the study of developmental processes in the intact organism. The developmental fate of every single somatic cell (959 in the adult hermaphrodite; 1031 in the adult male) has been mapped out. These patterns of cell lineage are largely invariant between individuals, in contrast to mammals where cell development from the embryo is more largely dependent on cellular cues. In both sexes, a large number of additional cells (131 in the hermaphrodite, most of which would otherwise become neurons), are eliminated by programmed cell death (apoptosis).
In addition, C. elegans is one of the simplest organisms with a nervous system. In the hermaphrodite, this comprises 302 neurons whose pattern of connectivity has been completely mapped out, and shown to be a small-world network.[4] Research has explored the neural mechanisms responsible for several of the more interesting behaviors shown by C. elegans, including chemotaxis, thermotaxis, mechanotransduction, and male mating behavior.
A useful feature of C. elegans is that it is relatively straightforward to disrupt the function of specific genes by RNA interference (RNAi). Silencing the function of a gene in this way can sometimes allow a researcher to infer what the function of that gene may be. The nematode can either be soaked in (or injected with) a solution of double stranded RNA, the sequence of which is complementary to the sequence of the gene that the researcher wishes to disable. Alternatively, worms can be fed on genetically transformed bacteria which express the double stranded RNA of interest.
C. elegans has also been useful in the study of meiosis. As sperm and egg nuclei move down the length of the gonad, they undergo a temporal progression through meiotic events. This progression means that every nucleus at a given position in the gonad will be at roughly the same step in meiosis, eliminating the difficulties of heterogeneous populations of cells.
The organism has also been identified as a model for nicotine dependence as it has been found to experience the same symptoms humans experience when they quit smoking.[5]
As for most model organisms, there is a dedicated online database for the species that is actively curated by scientists working in this field. The WormBase database attempts to collate all published information on C. elegans and other related nematodes. A reward of $5000 has been advertised on their website, for the finder of a new species of closely related nematode.[6] Such a discovery would broaden research opportunities with the worm.[7]
C. elegans Genome
C. elegans was the first multicellular organism to have its genome completely sequenced. The finished genome sequence was published in 1998,[8] although a number of small gaps were present (the last gap was finished by October 2002). The C. elegans genome sequence is approximately 100 million base pairs long and contains approximately 20,000 genes. The vast majority of these genes encode for proteins but there are likely to be as many as 1,000 RNA genes. Scientific curators continue to appraise the set of known genes, such that new gene predictions continue to be added and incorrect ones modified or removed.
In 2003, the genome sequence of the related nematode C. briggsae was also determined, allowing researchers to study the comparative genomics of these two organisms.[9] Work is now ongoing to determine the genome sequences of more nematodes from the same genus such as C. remanei,[10] C. japonica[11] and C. brenneri.[12] These newer genome sequences are being determined by using the whole genome shotgun technique which means that the resulting genome sequences are likely to not be as complete or accurate as C. elegans (which was sequenced using the 'hierarchical' or clone-by-clone approach).
The official version of the C. elegans genome sequence continues to change as and when new evidence reveals errors in the original sequencing (DNA sequencing is not an error-free process). Most changes are minor, adding or removing only a few base pairs (bp) of DNA. E.g. the WS169 release of WormBase (December 2006) lists a net gain of 6 bp to the genome sequence.[13] Occasionally more extensive changes are made, e.g. the WS159 release of May 2006 added over 300 bp to the sequence.[14]
C. elegans Evolution
It has been shown that a small number of conserved protein sequences from sponges are more similar to humans than to C. elegans.[15] This suggests that there has been an accelerated rate of evolution in the C. elegans lineage. The same study found that several phylogenetically ancient genes are not present in C. elegans.
C. elegans Scientific community
In 2002, the Nobel Prize in Physiology or Medicine was awarded to Sydney Brenner, H. Robert Horvitz and John Sulston for their work on the genetics of organ development and programmed cell death (PCD) in C. elegans. The 2006 Nobel Prize in Physiology or Medicine was awarded to Andrew Fire and Craig C. Mello, for their discovery of RNA interference in C. elegans.[16]. In 2008 Martin Chalfie shared a Nobel Prize in Chemistry for his work on green fluorescent protein (GFP) in C. elegans.
Because all research into C. elegans essentially started with Sydney Brenner in the 1970s, many scientists working in this field share a close connection to Brenner (they either worked as a post-doctoral or post-graduate researcher in Brenner's lab or in the lab of someone who previously worked with Brenner). Because most people who worked in his lab went on to establish their own worm research labs, there is now a fairly well documented 'lineage' of C. elegans scientists. This lineage was recorded in some detail at the 2003 International Worm Meeting and the results were stored in the Wormbase database.
C. elegans In the media
C. elegans made news when it was discovered that specimens had survived the Space Shuttle Columbia disaster in February 2003.[17] Later, in January 2009, it was announced that live samples of C.elegans from the University of Nottingham will spend two weeks on the International Space Station as part of a project to explore the effects of zero gravity on muscle development and its physiology. The emphasis of the research will be on the genetic basis of muscle atrophy. This has relevance to space travel, but also to individuals who are bed-ridden, geriatric or diabetic.[18]
See also about C. elegans
- Animal testing on invertebrates
C. elegans References
- ^ Brenner, S. (May 1974). "The Genetics of Caenorhabditis elegans" (PDF). Genetics 77: 71–94. http://dev.wormbase.org/papers/31_Brenner74.pdf.
- ^ Nayak, S., J. Goree & T. Schedl (2004). "fog-2 and the Evolution of Self-Fertile Hermaphroditism in Caenorhabditis". PLoS Biology 3 (1): e6. doi:. http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030006.
- ^ Shaham S. (March 14 2006). "Worming into the cell: Viral reproduction in Caenorhabditis elegans" (PDF). Proc Natl Acad Sci USA 103 (11): 3955–56. doi:. http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1449626&blobtype=pdf. . PMID 16537467
- ^ Watts D. J. & S. H. Strogatz (June 1998). "Collective dynamics of 'small-world' networks". Nature 393 (6684): 440–442. doi:. http://www.nature.com/nature/journal/v393/n6684/abs/393440a0.html.
- ^ Feng et al. (November 2006). "A C. elegans Model of Nicotine-Dependent Behavior: Regulation by TRP-Family Channels". Cell 127: 621–633. doi:. http://www.cell.com/content/article/abstract?uid=PIIS0092867406012955. . PMID 17081982
- ^ "Caenorhabditis isolation guide". WormBase. Retrieved on 2007-08-30.
- ^ Dolgin, Elie (August 2007). "Slime for a dime". Science 317 (5842): 1157. doi: .
- ^ The C. elegans Sequencing Consortium (1998). "Genome sequence of the nematode C. elegans: a platform for investigating biology". Science 282: 2012–2018. doi:. http://www.sciencemag.org/cgi/content/abstract/282/5396/2012. . PMID 9851916
- ^ Stein, L. D. et al. (2003). "The Genome Sequence of Caenorhabditis briggsae: A Platform for Comparative Genomics". PLoS Biology 1: 166–192. doi: .
- ^ Genome Sequencing Center. "Caenorhabditis remanei: Background". Washington University School of Medicine. Retrieved on 2008-07-11.
- ^ Genome Sequencing Center. "Caenorhabditis japonica: Background". Washington University School of Medicine. Retrieved on 2008-07-11.
- ^ Genome Sequencing Center. "Caenorhabditis brenneri: Background". Washington University School of Medicine. Retrieved on 2008-07-11.
- ^ "WormBaseWiki WS169 release notes". Wormbase. Retrieved on 2007-02-21.
- ^ "WormBaseWiki WS159 release notes". Wormbase. Retrieved on 2007-01-21.
- ^ Gamulin, V (December 2000). "Sponge proteins are more similar to those of Homo sapiens than to Caenorhabditis elegans". Biological Journal of the Linnean Society (Academic Press) 71 (4): 821–828.
- ^ Fire A, Xu S, Montgomery MK, Kostas SA, Driver SE, Mello CC (February 1998). "Potent and specific genetic interference by double-stranded RNA in Caenorhabditis elegans". Nature 391 (6669): 806–11. doi: . PMID 9486653.
- ^ "Worms survived Columbia disaster", BBC News (2003-05-01). Retrieved on 11 July 2008.
- ^ http://news.bbc.co.uk/1/hi/england/nottinghamshire/7835020.stm
C. elegans Publications
- Bird, Jean; Bird, Alan C. (1991). The structure of nematodes. Boston: Academic Press. pp. 1, 69–70, 152–153, 165, 224–225. ISBN 0-12-099651-0.
- Hope, Ian A. (1999). C. elegans: a practical approach. Oxford [Oxfordshire]: Oxford University Press. pp. 1–6. ISBN 0-19-963738-5.
- Riddle, D.L., T. Blumenthal, R. J. Meyer & J. R. Priess (1997). C. elegans II. Cold Spring Harbor Laboratory Press, New York. pp. 1–4, 679–683. ISBN 0-87969-532-3. http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=ce2.
C. elegans Online resources
- WormBase - an extensive online database covering the biology and genomics of C. elegans and other nematodes
- WormBook - a free online compendium of all aspects of C. elegans biology, including laboratory protocols
- Wormatlas - an online database for behavioral and structural anatomy of C. elegans
- Wellcome Trust Sanger Institute C. elegans page - half of the genome sequence is still maintained by this institute
- WashU Genome Sequencing Center C. elegans page - the institute maintaining the other half of the genome
- AceView WormGenes - another genome database for C. elegans, maintained at the NCBI
- TCNJ Worm Lab - Easy to follow protocols and pictures for C. elegans research. Made by undergrads for undergrads.
- Worm Classroom - An education portal for C. elegans
- Textpresso - WormBase search engine
- C. elegans movies - Timelapse films made by C. elegans researchers worldwide
- C. elegans II - a free online textbook.
- Silencing Genomes RNA interference (RNAi) experiments and bioinformatics in C. elegans for education. From the Dolan DNA Learning Center of Cold Spring Harbor Laboratory.
- C.elegans 3D model by the Ewbank Lab - Videos and photos that explain the basic anatomy of C. elegans
- WormTracker
C. elegans Nobel lectures
- Brenner S (2002) Nature's Gift to Science. In. http://nobelprize.org/nobel_prizes/medicine/laureates/2002/brenner-lecture.pdf
- Horvitz HR (2002) Worms, Life and Death. In. http://nobelprize.org/nobel_prizes/medicine/laureates/2002/horvitz-lecture.pdf
- Sulston JE (2002) The Cell Lineage and Beyond. In. http://nobelprize.org/nobel_prizes/medicine/laureates/2002/sulston-lecture.pdf