Corazonin
Encyclopedia
Corazonin is a highly conserved neuropeptide
found in many insect
s, in particular locust
s and cockroach
es.
) with the amino acid sequence Glu-Thr-Phe-Gln-Tyr-Ser-Arg-Gly-Trp-Thr-Asn-amide. It is blocked by pGlu at its N-terminal side and amidated at its C-terminus. This form is called [Arg(7)]-corazonin. Other forms include [His(7)]-corazonin, [Thr(4), His(7)]-corazonin and [Tyr(3), Gln(7), Gln(10)]-corazonin.
in the American cockroach
(Periplaneta americana). Due to its ability to accelerate the heart beat in P. americana it was named corazonin, from 'corazon', the Spanish word for 'heart'.
When first identified in locust
s, corazonin was initially named 'dark-color-inducing neurohormone' or 'dark pigmentotropin' due to its ability to induce dark pigmentation in some insect
s.
es such as the American cockroach
(Periplaneta americana).
[His(7)]-corazonin is found in certain locust
s, including the migratory locust
(Locusta migratoria) and the desert locust
(Schistocerca gregaria), the stick insect Carausius morosus
, and in wasp
s (Vespidae).
[Thr(4), His(7)]-corazonin appears only to be found in bee
s, such as the honey bee
(Apis mellifera).
[Tyr(3), Gln(7), Gln(10)]-corazonin is present in wasps.
Corazonin has also been identified in the genus of flies Drosophila
, the cricket Gryllus bimaculatus
and the silkworm Bombyx mori
.
In the American cockroach Periplaneta americana, [Arg(7)]-corazonin acts as a cardiostimulatory neuropeptide and accelerates the heart beat. It also causes contractions of the hyperneural muscle, however this has not been seen in other cockroach species.
[His(7)]-corazonin acts as a hormonal factor in locusts and can cause dark pigmentation in albino migratory locusts (Locusta migratoria) and in green nymphs of the desert locust Schistocerca gregaria. While corazonins found in crickets and moths have no effect on body colour of the crickets or moths themselves, they can cause dark pigmentation in albino nymphs of the migratory locust (Locusta migratoria).
In silkworms (Bombyx mori
), corazonin reduces the spinning rate of silk.
Neuropeptide
Neuropeptides are small protein-like molecules used by neurons to communicate with each other. They are neuronal signaling molecules, influence the activity of the brain in specific ways and are thus involved in particular brain functions, like analgesia, reward, food intake, learning and...
found in many insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s, in particular locust
Locust
Locusts are the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory...
s and cockroach
Cockroach
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations...
es.
Structure
Corazonin is an undecapeptide (11 amino-acid peptidePeptide
Peptides are short polymers of amino acid monomers linked by peptide bonds. They are distinguished from proteins on the basis of size, typically containing less than 50 monomer units. The shortest peptides are dipeptides, consisting of two amino acids joined by a single peptide bond...
) with the amino acid sequence Glu-Thr-Phe-Gln-Tyr-Ser-Arg-Gly-Trp-Thr-Asn-amide. It is blocked by pGlu at its N-terminal side and amidated at its C-terminus. This form is called [Arg(7)]-corazonin. Other forms include [His(7)]-corazonin, [Thr(4), His(7)]-corazonin and [Tyr(3), Gln(7), Gln(10)]-corazonin.
History
Corazonin was first identified as a cardiostimulatory neuropeptideNeuropeptide
Neuropeptides are small protein-like molecules used by neurons to communicate with each other. They are neuronal signaling molecules, influence the activity of the brain in specific ways and are thus involved in particular brain functions, like analgesia, reward, food intake, learning and...
in the American cockroach
American cockroach
The American cockroach , also known as the waterbug, or misidentified as the palmetto bug , is the largest species of common cockroach, and often considered a pest. None of the Periplaneta species are endemic to the Americas; despite the name, P...
(Periplaneta americana). Due to its ability to accelerate the heart beat in P. americana it was named corazonin, from 'corazon', the Spanish word for 'heart'.
When first identified in locust
Locust
Locusts are the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory...
s, corazonin was initially named 'dark-color-inducing neurohormone' or 'dark pigmentotropin' due to its ability to induce dark pigmentation in some insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s.
Where corazonin is found
[Arg(7)]-corazonin was originally identified in cockroachCockroach
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations...
es such as the American cockroach
American cockroach
The American cockroach , also known as the waterbug, or misidentified as the palmetto bug , is the largest species of common cockroach, and often considered a pest. None of the Periplaneta species are endemic to the Americas; despite the name, P...
(Periplaneta americana).
[His(7)]-corazonin is found in certain locust
Locust
Locusts are the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory...
s, including the migratory locust
Migratory locust
The migratory locust is the most widespread locust species, and the only species in the genus Locusta. It occurs throughout Africa, Asia, Australia and New Zealand. It used to be common in Europe but has now become rare there...
(Locusta migratoria) and the desert locust
Desert locust
Plagues of the desert locust have threatened agricultural production in Africa, the Middle East, and Asia for centuries. The livelihood of at least one-tenth of the world’s human population can be affected by this voracious insect...
(Schistocerca gregaria), the stick insect Carausius morosus
Carausius morosus
Carausius morosus is a species of phasmid that is often kept by schools and individuals as pets. Culture stocks originate from an original collection from Tamil Nadu, India. Like the majority of the phasmatodea, they are nocturnal. Culture stocks are parthenogenetic females that can reproduce...
, and in wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...
s (Vespidae).
[Thr(4), His(7)]-corazonin appears only to be found in bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s, such as the honey bee
Honey bee
Honey bees are a subset of bees in the genus Apis, primarily distinguished by the production and storage of honey and the construction of perennial, colonial nests out of wax. Honey bees are the only extant members of the tribe Apini, all in the genus Apis...
(Apis mellifera).
[Tyr(3), Gln(7), Gln(10)]-corazonin is present in wasps.
Corazonin has also been identified in the genus of flies Drosophila
Drosophila
Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" or more appropriately pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit...
, the cricket Gryllus bimaculatus
Gryllus bimaculatus
Gryllus bimaculatus is one of many cricket species known as the Field cricket. Also known as the African or Mediterranean field cricket or as the two-spotted cricket, it can be discriminated from other Gryllus species by the two dot-like marks on the base of its wings.This species of cricket is...
and the silkworm Bombyx mori
Bombyx mori
The silkworm is the larva or caterpillar of the domesticated silkmoth, Bombyx mori . It is an economically important insect, being a primary producer of silk...
.
Function
Corazonin has no universally recognized function.In the American cockroach Periplaneta americana, [Arg(7)]-corazonin acts as a cardiostimulatory neuropeptide and accelerates the heart beat. It also causes contractions of the hyperneural muscle, however this has not been seen in other cockroach species.
[His(7)]-corazonin acts as a hormonal factor in locusts and can cause dark pigmentation in albino migratory locusts (Locusta migratoria) and in green nymphs of the desert locust Schistocerca gregaria. While corazonins found in crickets and moths have no effect on body colour of the crickets or moths themselves, they can cause dark pigmentation in albino nymphs of the migratory locust (Locusta migratoria).
In silkworms (Bombyx mori
Bombyx mori
The silkworm is the larva or caterpillar of the domesticated silkmoth, Bombyx mori . It is an economically important insect, being a primary producer of silk...
), corazonin reduces the spinning rate of silk.