vector
Vector most often refers to:
*Euclidean vector, a quantity with a magnitude and a direction
*Vector (epidemiology), an agent that carries and transmits an infectious pathogen into another living organism
Vector may also refer to:
Mathematic ...
juvenile hormone Juvenile hormones (JHs) are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. The first discovery of a JH was by Vincent Wigglesworth. JHs regulate development, reproduction, diapause, and polyphenisms.The chem ...
which prevents the premature development into an adult. The removal of the head during any larval stage causes early development into an adult, whereas the implantation of a juvenile head during the fifth larval stage results in a giant sixth stage larva.
The adult secretes compounds into the wound during feeding, including
lipocalin
The lipocalins are a family of proteins which transport small hydrophobic molecules such as steroids, bilins, retinoids, and lipids and most lipocalins are also able to bind to complexed iron (via siderophores or flavonoids) as well as heme. They ...
s. These lipocalins were demonstrated to serve various functions including sequestering
amine
In chemistry, amines (, ) are compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are formally derivatives of ammonia (), wherein one or more hydrogen
Hydrogen is the chemical element wi ...
s - especially serotonin - to prevent vasoconstriction (and possibly coagulation) in the host by Andersen et al 2003.
The male reproductive system of R. prolixus contains four accessory glands, three which are responsible for producing the
spermathecae
The spermatheca (pronounced plural: spermathecae ), also called receptaculum seminis (plural: receptacula seminis), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, oligochaeta worms and certain other in ...
and one which is responsible for the movement of spermatozoa from the spermatophore into the female. Once mating occurs, the sperm move through the reproductive system of the female through peristatic waves. The female then stores the sperm until fertilization.
As disease vector
Chagas disease is caused by the parasitic protozoan ''
Trypanosoma cruzi
''Trypanosoma cruzi'' is a species of parasitic euglenoids. Among the protozoa, the trypanosomes characteristically bore tissue in another organism and feed on blood (primarily) and also lymph. This behaviour causes disease or the likelihood o ...
''.
Infection with Chagas disease occurs after ''Rhodnius'' releases protozoans in its
feces immediately following a blood meal. The parasite enters the victim through
the bite wound after the human host scratches the bite. Infection may also occur via blood
transfusion and ingestion of food contaminated with kissing bug feces.
Nitrophorin Nitrophorins are hemoproteins found in the saliva of blood-feeding insects. Saliva of the blood-sucking bug ''Rhodnius prolixus'' contains at least seven homologous nitrophorins, designated NP1 to NP7 in order of their relative abundance in the gla ...
s
*
Hematophagy
Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice by certain animals of feeding on blood (from the Greek words αἷμα ' "blood" and φαγεῖν ' "to eat"). Since blood is a fluid tissue rich in nutritious pr ...
Proctolin
Proctolin is a neuropeptide present in insects and crustaceans. It was first found in '' Periplaneta americana'', a species of cockroach in 1975. Proctolin was extracted from 125,000 cockroaches and the Edman degradation was carried out on the sam ...
References
Further reading
* William C Marquardt ''et al'' (2004), Chapter 5: Kissing Bugs and Bedbugs the Heteroptera, Biology of Disease Vectors (2nd edition), Academic Press,