Hemolin is an

immunoglobulin An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

-like protein exclusively found in

Lepidoptera Lepidoptera ( ) is an order (biology), order of insects that includes butterfly, butterflies and moths (both are called lepidopterans). About 180,000 species of the Lepidoptera are described, in 126 Family (biology), families and 46 Taxonomic r ...

(moths and butterflies). It was first discovered in immune-challenged pupae of '' Hyalophora cecropia'' and ''

Manduca sexta ''Manduca sexta'' is a moth of the family Sphingidae present through much of the Americas. The species was Species description, first described by Carl Linnaeus in his 1763 ''Centuria Insectorum''. Commonly known as the Carolina sphinx moth and ...

''. Hemolin has a horseshoe crystal structure with four domains and resembles the developmental protein neuroglian. Hemolin and neuroglian 3D

Hemolin increases 18-fold up to 7 mg/ml following injection of bacteria in ''H. cecropia''. Induction of Hemolin in moths after bacterial injection have been shown in several species including '' Antheraea pernyi'', '' Bombyx mori'', '' Helicoverpa zea'', ''

Heliothis virescens ''Chloridea virescens'', commonly known as the tobacco budworm, is a moth of the family Noctuidae found throughout the eastern and southwestern United States along with parts of Central America and South America. It is a major pest of field cro ...

'', ''

Hyphantria cunea The fall webworm (''Hyphantria cunea'') is a moth in the family Erebidae known principally for its larval stage, which creates the characteristic webbed nests on the tree limbs of a wide variety of hardwoods in the late summer and fall. It is con ...

'', and '' Samia cynthia''. Hemolin has also been suggested to participate in the immune response to virus infection and shown to bind to virus particles. It is expressed in response to

dsRNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

in a dose-dependent manner. '' Galleria melonella'' responds to caffeine intake by increased Hemolin protein expression. Hemolin is thought to be a gene duplication of the developmental protein neuroglian, but has lost two of the protein domains that neuroglian contains. In the potential function as a developmental protein, Hemolin has been shown to increase close to pupation in ''

'', and is induced during diapause and by

20-Hydroxyecdysone 20-Hydroxyecdysone (ecdysterone or 20E) is a naturally occurring ecdysteroid hormone which controls the ecdysis (moulting) and metamorphosis of arthropods. It is therefore one of the most common moulting hormones in insects, crabs, etc. It is als ...

in ''

Lymantria dispar ''Lymantria dispar'', also known as the gypsy moth or the spongy moth, is a species of moth in the family Erebidae. ''Lymantria dispar'' is subdivided into several subspecies, with subspecies such as ''L. d. dispar'' and ''L. d. japonica'' bei ...

''. RNAi of Hemolin causes malformation in ''H. cecropia''.{{cite journal, last=Bettencourt, first=R., author2=Terenius, O. , author3=Faye, I. , title=Hemolin gene silencing by ds-RNA injected into Cecropia pupae is lethal to next generation embryos, journal=Insect Molecular Biology, date=June 2002, volume=11, issue=3, pages=267–271, doi=10.1046/j.1365-2583.2002.00334.x, pmid=12000646, doi-access=free

References

Immunology Insect immunity

See also

References