The nematode worm Caenorhabditis elegans was first studied in the laboratory by Victor Nigon and Ellsworth Dougherty in the 1940s, but came to prominence after being adopted by Sydney Brenner in 1963 as a model organism for the study of developmental biology using genetics. In 1974, Brenner published the results of his first genetic screen, which isolated hundreds of mutants with morphological and functional phenotypes, such as being uncoordinated. In the 1980s, John Sulston and co-workers identified the lineage of all 959 cells in the adult hermaphrodite, the first genes were cloned, and the physical map began to be constructed. In 1998, the worm became the first multi-cellular organism to have its genome sequenced. [1] [2] Notable research using C. elegans includes the discoveries of caspases, RNA interference, and microRNAs. Eight scientists have won the Nobel Prize for their work on C. elegans.
C. elegans was first described in 1900 by Émile Maupas, who isolated it from soil in Algeria. [3] Ellsworth Dougherty proposed in 1948 that free-living nematodes of the sub-order Rhabditina might be useful for genetic study, noting their relative structural simplicity and invariant cell lineage (eutely). [4] Dougherty and Victor Nigon obtained the first mutant, from a laboratory culture of the closely related nematode Caenorhabditis briggsae . [5] However much of the early laboratory work on Caenorhabditis nematodes was directed towards the establishment of a defined axenic culture medium. [6]
By the early 1960s, Sydney Brenner had made several important contributions to molecular biology, notably a demonstration (with Francis Crick and other colleagues) that the genetic code is triplet in nature. [7] In June 1963, he wrote to Max Perutz, then the head of the MRC Laboratory of Molecular Biology, Cambridge, proposing future research:
It is now widely realized that nearly all the 'classical' problems of molecular biology have either been solved or will be solved in the next decade...Because of this, I have long felt that the future of molecular biology lies in the extension of research to other fields of biology, notably development and the nervous system...I would like to tame a small metazoan organism to study development directly. My ideas on this are still fluid and I cannot specify this in greater detail at the present time.
— Letter to Max Perutz, 5 June 1963 [8]
By the end of that year, his thoughts were more concrete:
Part of the success of molecular genetics was due to the use of extremely simple organisms which could be handled in large numbers...We should like to attack the problem of cellular development in a similar fashion, choosing the simplest possible differentiated organism and subjecting it to the analytical methods of microbial genetics...We think we have a good candidate in the form of a small nematode worm, Caenorhabditis briggsiae...To start with we propose to identify every cell in the worm and trace lineages. We shall also investigate the constancy of development and study its genetic control by looking for mutants.
Brenner obtained C. elegans from Dougherty and began to study them in the laboratory by December 1963. [9]
C. elegans is amenable to transgenesis, the process of introducing foreign genetic material into the genome. [10] The most frequent method for generating transgenic worms is to inject exogenous DNA into the syncytial germ line; biolistic transformation can also be used. [10]
Caenorhabditis elegans is a free-living transparent nematode about 1 mm in length that lives in temperate soil environments. It is the type species of its genus. The name is a blend of the Greek caeno- (recent), rhabditis (rod-like) and Latin elegans (elegant). In 1900, Maupas initially named it Rhabditides elegans. Osche placed it in the subgenus Caenorhabditis in 1952, and in 1955, Dougherty raised Caenorhabditis to the status of genus.
Sydney Brenner was a South African biologist. In 2002, he shared the Nobel Prize in Physiology or Medicine with H. Robert Horvitz and Sir John E. Sulston. Brenner made significant contributions to work on the genetic code, and other areas of molecular biology while working in the Medical Research Council (MRC) Laboratory of Molecular Biology in Cambridge, England. He established the roundworm Caenorhabditis elegans as a model organism for the investigation of developmental biology, and founded the Molecular Sciences Institute in Berkeley, California, United States.
Howard Robert Horvitz ForMemRS NAS AAA&S APS NAM is an American biologist whose research on the nematode worm Caenorhabditis elegans, was awarded the 2002 Nobel Prize in Physiology or Medicine, together with Sydney Brenner and John E. Sulston, whose "seminal discoveries concerning the genetic regulation of organ development and programmed cell death" were "important for medical research and have shed new light on the pathogenesis of many diseases".
Sir John Edward Sulston was a British biologist and academic who won the Nobel Prize in Physiology or Medicine for his work on the cell lineage and genome of the worm Caenorhabditis elegans in 2002 with his colleagues Sydney Brenner and Robert Horvitz at the MRC Laboratory of Molecular Biology. He was a leader in human genome research and Chair of the Institute for Science, Ethics and Innovation at the University of Manchester. Sulston was in favour of science in the public interest, such as free public access of scientific information and against the patenting of genes and the privatisation of genetic technologies.
WormBook is an open access, comprehensive collection of original, peer-reviewed chapters covering topics related to the biology of the nematode worm Caenorhabditis elegans . WormBook also includes WormMethods, an up-to-date collection of methods and protocols for C. elegans researchers.
Caenorhabditis briggsae is a small nematode, closely related to Caenorhabditis elegans. The differences between the two species are subtle. The male tail in C. briggsae has a slightly different morphology from C. elegans. Other differences include changes in vulval precursor competence and the placement of the excretory duct opening. C. briggsae is frequently used to study the differences between it and the more intimately understood C. elegans, especially at the DNA and protein sequence level. Several mutant strains of C. briggsae have also been isolated that facilitate genetic analysis of this organism. C. briggsae, like C. elegans, is a hermaphrodite. The genome sequence for C. briggsae was determined in 2003.
Cynthia Jane Kenyon is an American molecular biologist and biogerontologist known for her genetic dissection of aging in a widely used model organism, the roundworm Caenorhabditis elegans. She is the vice president of aging research at Calico Research Labs, and emeritus professor of biochemistry and biophysics at the University of California, San Francisco (UCSF).
Caenorhabditis is a genus of nematodes which live in bacteria-rich environments like compost piles, decaying dead animals and rotting fruit. The name comes from Greek: caeno- ; rhabditis = rod-like.
John Graham White is an Emeritus Professor of Anatomy and Molecular Biology at the University of Wisconsin–Madison. His research interests are in the biology of the model organism Caenorhabditis elegans and laser microscopy.
Most animal testing involves invertebrates, especially Drosophila melanogaster, a fruit fly, and Caenorhabditis elegans, a nematode. These animals offer scientists many advantages over vertebrates, including their short life cycle, simple anatomy and the ease with which large numbers of individuals may be studied. Invertebrates are often cost-effective, as thousands of flies or nematodes can be housed in a single room.
DAF-16 is the sole ortholog of the FOXO family of transcription factors in the nematode Caenorhabditis elegans. It is responsible for activating genes involved in longevity, lipogenesis, heat shock survival and oxidative stress responses. It also protects C.elegans during food deprivation, causing it to transform into a hibernation - like state, known as a Dauer. DAF-16 is notable for being the primary transcription factor required for the profound lifespan extension observed upon mutation of the insulin-like receptor DAF-2. The gene has played a large role in research into longevity and the insulin signalling pathway as it is located in C. elegans, a successful ageing model organism.
Jonathan Alan Hodgkin is a British biochemist. He is the Professor of Genetics at the University of Oxford and an emeritus fellow of Keble College, Oxford.
Caenorhabditis elegans- microbe interactions are defined as any interaction that encompasses the association with microbes that temporarily or permanently live in or on the nematode C. elegans. The microbes can engage in a commensal, mutualistic or pathogenic interaction with the host. These include bacterial, viral, unicellular eukaryotic, and fungal interactions. In nature C. elegans harbours a diverse set of microbes. In contrast, C. elegans strains that are cultivated in laboratories for research purposes have lost the natural associated microbial communities and are commonly maintained on a single bacterial strain, Escherichia coli OP50. However, E. coli OP50 does not allow for reverse genetic screens because RNAi libraries have only been generated in strain HT115. This limits the ability to study bacterial effects on host phenotypes. The host microbe interactions of C. elegans are closely studied because of their orthologs in humans. Therefore, the better we understand the host interactions of C. elegans the better we can understand the host interactions within the human body.
Caenorhabditis nigoni is a male-female species in the Elegans group of the genus Caenorhabditis, first identified and described as "Caenorhabditis species 9" or "C. sp. 9" before being renamed as "C. nigoni". The specific epithet is a tribute to Victor Nigon who first studied Caenorhabditis elegans in the laboratory with Ellsworth Dougherty in the 1940s. Isolates come from the Democratic Republic of the Congo and Kerala, India.
Caenorhabditis doughertyi is a species of nematodes in the genus Caenorhabditis. Prior to 2014, it was referred to as C. sp. 10
Victor Marc Nigon was a biologist who was first to study the nematode worm Caenorhabditis elegans in the laboratory, with Ellsworth Dougherty, in the 1940s.
Ellsworth C. Dougherty was a biologist who was first to study the nematode worm Caenorhabditis elegans in the laboratory, with Victor Nigon, in the 1940s. He did most of his studies and medical work in California.
Worm bagging is a form of vivipary observed in nematodes, namely Caenorhabditis elegans. The process is characterized by eggs hatching within the parent and the larvae proceeding to consume and emerge from the parent.
Eileen Southgate is a British biologist who mapped the complete nervous system of the roundworm Caenorhabditis elegans, together with John White, Nichol Thomson, and Sydney Brenner. The work, done largely by hand-tracing thousands of serial section electron micrographs, was the first complete nervous system map of any animal and it helped establish C. elegans as a model organism. Among other projects carried out as a laboratory assistant at the Medical Research Council Laboratory of Molecular Biology (MRC-LMB), Southgate contributed to work on solving the structure of hemoglobin with Max Perutz and John Kendrew, and investigating the causes of sickle cell disease with Vernon Ingram.
Warwick Llewellyn Nicholas (1926–2010) was an Australian zoologist known as a pioneer in the field of nematology. He was a foundational member of the Australian Society for Parasitology (ASP) and in 1964, he organised the first ASP meeting. He became President of the Society in 1978, before being an elected Fellow from 1979.