Allatostatins are neuropeptide

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...

 hormone

Hormone

A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

s in 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 and crustacea. They have a twofold function: they both inhibit the generation of juvenile hormone

Juvenile hormone

Juvenile hormones are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. JHs regulate development, reproduction, diapause, and polyphenisms....

  and reduce their food intake. They are therefore putative targets for insecticide research.

Types of Allatostatin

Three biochemically distinct types of Allatostatin have been described: A, B and C. Although originally identified in different insects, all three types are found in the fruitfly, Drosophila. These types of Allatostatin are not normally found in the same neurons, and so probably have different roles.

Control of food intake

Allatostatin is found in the cells in a small neuronal cluster, the frontal ganglion. It is also present in the axons which leave the frontal ganglion and run across the surface of the gut. Application of low concentrations of Allatostatin inhibit the spontaneous contractions of the gut. All three forms of Allatostatin appear to inhibit gut motility in all the insects which have been tested.

Interaction with Juvenile hormone

Juvenile hormone is synthesised in the corpora allata. In every insect tested, at least one of the three types of Allatostatin inhibits the biosynthesis of juvenile hormone. This is achieved by paracrine release of Allatostatin from neurons in the brain which terminate in the corpora allata. The signal is transduced by GPCR receptors, but the intracellular pathway is not yet known. Other amine

Amine

Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...

 and neuropeptide

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...

neurotransmitters may also inhibit juvenile hormone biosynthesis.