The nematode worm ''
Caenorhabditis elegans'' was first studied in the laboratory by
Victor Nigon
Victor Marc Nigon (born 11 October 1920 in Metz, France, died 5 July 2015) was a biologist who was first to study the nematode worm ''Caenorhabditis elegans'' in the laboratory, with Ellsworth Dougherty, in the 1940s.
Jean-Louis Brun, a student of ...
and
Ellsworth Dougherty in the 1940s, but came to prominence after being adopted by
Sydney Brenner
Sydney Brenner (13 January 1927 – 5 April 2019) 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 ...
in 1963 as a
model organism for the study of
developmental biology using
genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar wor ...
. In 1974, Brenner published the results of his first
genetic screen
A genetic screen or mutagenesis screen is an experimental technique used to identify and select individuals who possess a phenotype of interest in a mutagenized population. Hence a genetic screen is a type of phenotypic screen. Genetic screens c ...
, which isolated hundreds of
mutants
In biology, and especially in genetics, a mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism. It ...
with morphological and functional
phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological pr ...
s, such as being
uncoordinated. In the 1980s,
John Sulston
Sir John Edward Sulston (27 March 1942 – 6 March 2018) 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 ...
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
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding g ...
sequenced.
Notable research using ''C. elegans'' includes the discoveries of
caspases,
RNA interference
RNA interference (RNAi) is a biological process in which RNA molecules are involved in sequence-specific suppression of gene expression by double-stranded RNA, through translational or transcriptional repression. Historically, RNAi was known by ...
, and
microRNAs
MicroRNA (miRNA) are small, single-stranded, non-coding RNA molecules containing 21 to 23 nucleotides. Found in plants, animals and some viruses, miRNAs are involved in RNA silencing and post-transcriptional regulation of gene expression. miR ...
. Six scientists have won the
Nobel prize
The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...
for their work on ''C. elegans''.
Early research
''C. elegans'' was first described in 1900 by
Émile Maupas
François Émile Maupas (2 July 1842 in Vaudry – 18 October 1916 in Algiers) was a French librarian, protozoologist, cytologist, and botanist. Maupas contributed to ideas on the life cycle and reproduction of the ciliates. He founded the ...
, who isolated it from soil in
Algeria
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, relig ...
. Ellsworth Dougherty proposed in 1948 that free-living nematodes of the sub-order
Rhabditina
Subclass Rhabditia is mostly composed of parasitic nematodes (particularly in the Strongylida), though there are some free-living species as well (particularly in the Rhabditida). Phasmids (posterior sensory structures) are well-developed, whil ...
might be useful for genetic study, noting their relative structural simplicity and invariant cell lineage (
eutely Eutelic organisms have a fixed number of somatic cells when they reach maturity, the exact number being relatively constant for any one species. This phenomenon is also referred to as cell constancy. Development proceeds by cell division until matur ...
). Dougherty and Victor Nigon obtained the first
mutant
In biology, and especially in genetics, a mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism. It ...
, from a laboratory culture of the closely related nematode ''
Caenorhabditis briggsae
''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 di ...
''. However much of the early laboratory work on ''Caenorhabditis'' nematodes was directed towards the establishment of a defined
axenic
In biology, axenic (, ) describes the state of a culture in which only a single species, variety, or strain of organism is present and entirely free of all other contaminating organisms. The earliest axenic cultures were of bacteria or unicellul ...
culture medium.
Brenner's search for a new model system
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.
In June 1963, he wrote to
Max Perutz
Max Ferdinand Perutz (19 May 1914 – 6 February 2002) was an Austrian-born British molecular biologist, who shared the 1962 Nobel Prize for Chemistry with John Kendrew, for their studies of the structures of haemoglobin and myoglobin. He went ...
, then the head of the
MRC Laboratory of Molecular Biology
The Medical Research Council (MRC) Laboratory of Molecular Biology (LMB) is a research institute in Cambridge, England, involved in the revolution in molecular biology which occurred in the 1950–60s. Since then it has remained a major medical r ...
, Cambridge, proposing future research:
By the end of that year, his thoughts were more concrete:
Brenner obtained ''C. elegans'' from Dougherty and began to study them in the laboratory by December 1963.
Transgenesis
''C. elegans'' is amenable to
transgenesis
Gene delivery is the process of introducing foreign genetic material, such as DNA or RNA, into host cells. Gene delivery must reach the genome of the host cell to induce gene expression. Successful gene delivery requires the foreign gene deli ...
, the process of introducing foreign genetic material into the genome.
The most frequent method for generating transgenic worms is to
inject exogenous DNA into the syncytial germ line;
biolistic transformation can also be used.
See also
*
History of model organisms
The history of model organisms began with the idea that certain organisms can be studied and used to gain knowledge of other organisms or as a control (ideal) for other organisms of the same species. Model organisms offer standards that serve as ...
References
Caenohabditis elegans
Caenorhabditis elegans
{{Rhabditida-stub