''Caenorhabditis remanei'' is a species of

nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

found in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

and

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

, and likely lives throughout the

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

world. Several strains have been developed in the laboratory.''C. remanei''.
The Genome Center at Washington University.

Habitat

This 1-mm nematode lives in

soil Soil, also commonly referred to as earth or dirt, is a mixture of organic matter, minerals, gases, liquids, and organisms that together support life. Some scientific definitions distinguish ''dirt'' from ''soil'' by restricting the former te ...

compost Compost is a mixture of ingredients used as plant fertilizer and to improve soil's physical, chemical and biological properties. It is commonly prepared by decomposing plant, food waste, recycling organic materials and manure. The resulting m ...

, and similar materials, where it consumes

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...

. It may be found in association with soil-living invertebrates such as

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

slug Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced shell, or only a smal ...

s, and

pill bugs Armadillidiidae is a family of woodlice, a terrestrial crustacean group in the order Isopoda. Unlike members of some other woodlice families, members of this family can roll into a ball, an ability they share with the outwardly similar but unre ...

. It lives with the snail '' Fruticicola sieboldiana'' in

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

. It has been associated with the

isopod Isopoda is an order of crustaceans that includes woodlice and their relatives. Isopods live in the sea, in fresh water, or on land. All have rigid, segmented exoskeletons, two pairs of antennae, seven pairs of jointed limbs on the thorax, an ...

s '' Trachelipus rathkii'', ''

Armadillidium nasatum ''Armadillidium nasatum'' is a large, Western European-based species of woodlouse that has been introduced to North America, along with ''Armadillidium vulgare'' also found in other parts of Europe. Description ''Armadillidium nasatum'' can ...

'', ''

Cylisticus convexus ''Cylisticus convexus'', the curly woodlouse, is a species of woodlouse A woodlouse (plural woodlice) is an isopod crustacean from the polyphyleticThe current consensus is that Oniscidea is actually triphyletic suborder Oniscidea withi ...

'', and ''

Porcellio scaber ''Porcellio scaber'' (otherwise known as the common rough woodlouse or simply rough woodlouse), is a species of woodlouse native to Europe but with a cosmopolitan distribution. They are often found in large numbers in most regions, with many spe ...

'' in

Ohio Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a population of nearly 11.8 million, is the seventh-most populous and tenth-most densely populated. The sta ...

.Baird, S. E. (1999)
Natural and experimental associations of ''Caenorhabditis remanei'' with ''Trachelipus rathkii'' and other terrestrial isopods.
''Nematology'' 1:5 471.

Genetics

The

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 ge ...

of this nematode has been

sequenced In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which suc ...

, and it was found to contain about 26,000

gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a ba ...

s.Haag, E. S., ''et al.'' (2008)
''Caenorhabditis'' evolution: if they all look alike, you aren’t looking hard enough.
''Trends in Genetics'' 23:3. This species groups with '' C. latens'' in the 'Elegans' supergroup in phylogenetic studies.

Mating and reproduction

Unlike many other ''Caenorhabditis'' species, which are

hermaphrodite In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrate ...

s, ''C. remanei'' has both males and females. The male of this species employs a

mating plug A mating plug, also known as a copulation plug, sperm plug, vaginal plug, or sphragis (Latin, from Greek σφραγίς ''sphragis'', "a seal"), is gelatinous secretion used in the mating of some species. It is deposited by a male into a female ge ...

.Timmermeyer, N., ''et al.'' (2010)
The function of copulatory plugs in ''Caenorhabditis remanei'': hints for female benefits.
''Frontiers in Zoology'' 7:28. This species can

hybridize Hybridization (or hybridisation) may refer to: *Hybridization (biology), the process of combining different varieties of organisms to create a hybrid *Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals *Nu ...

with ''

Caenorhabditis brenneri ''Caenorhabditis brenneri'' is a small nematode, closely related to the model organism '' Caenorhabditis elegans''. Its genome is being sequenced by Washington University in St. Louis Genome Sequencing Center. This species has previously been re ...

'', but only when ''C. remanei'' males mate with ''C. brenneri'' females, and then the offspring are apparently sterile.Sudhaus, W. and K. Kiontke. (2007)
Comparison of the cryptic nematode species ''Caenorhabditis brenneri'' sp. n. and ''C. remanei'' (Nematoda: Rhabditidae) with the stem species pattern of the ''Caenorhabditis elegans'' group.
''Zootaxa'' 1456 45-62. When ''C. remanei'' individuals that were derived from recently isolated natural populations were

inbred Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and o ...

they showed dramatic reductions in brood size and relative fitness compared to outcrossed individuals.Dolgin ES, Charlesworth B, Baird SE, Cutter AD. Inbreeding and outbreeding depression in Caenorhabditis nematodes. Evolution. 2007 Jun;61(6):1339-52. doi: 10.1111/j.1558-5646.2007.00118.x. PMID: 17542844 Over time the decline in fitness accumulated and nearly 90% of inbred lines went extinct.

References

External links

''C. remanei'' Genome Sequencing.
{{Taxonbar, from=Q5016840 remanei Fauna of North America Parasitic nematodes of animals