Inducible glutathione S-transferase (IrGST1) from the tick Ixodes ricinus is a haem-binding protein

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60076658%3A12310%2F18%3A43897559" target="_blank" >RIV/60076658:12310/18:43897559 - isvavai.cz</a>

Alternative codes found

RIV/60077344:_____/18:00498795

Result on the web

<a href="https://reader.elsevier.com/reader/sd/pii/S0965174818300213?token=F0C4738DC9FC9D34324FA8309105F21E53DB734EE108D6906886986FD4993DE3C2F1E97FC2A9D04F33EECF32C7488886" target="_blank" >https://reader.elsevier.com/reader/sd/pii/S0965174818300213?token=F0C4738DC9FC9D34324FA8309105F21E53DB734EE108D6906886986FD4993DE3C2F1E97FC2A9D04F33EECF32C7488886</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ibmb.2018.02.002" target="_blank" >10.1016/j.ibmb.2018.02.002</a>

Result language

angličtina

Original language name

Inducible glutathione S-transferase (IrGST1) from the tick Ixodes ricinus is a haem-binding protein

Original language description

Blood-feeding parasites are inadvertently exposed to high doses of potentially cytotoxic haem liberated upon host blood digestion. Detoxification of free haem is a special challenge for ticks, which digest haemoglobin intracellularly. Ticks lack a haem catabolic mechanism, mediated by haem oxygenase, and need to dispose of vast majority of acquired haem via its accumulation in haemosomes. The knowledge of individual molecules involved in the maintenance of haem homeostasis in ticks is still rather limited. RNA-seq analyses of the Ixodes ricinus midguts from blood- and serum-fed females identified an abundant transcript of glutathione S-wansferase (gst) to be substantially up-regulated in the presence of red blood cells in the diet. Here, we have determined the full sequence of this encoding gene, ir-gstl, and found that it is homologous to the delta-/epsilon-class of GSTs. Phylogenetic analyses across related chelicerates revealed that only one clear IrGST1 orthologue could be found in each available transcriptome from hard and soft ticks. These orthologues create a well-supported Glade clearly separated from other ticks&apos; or mites&apos; delta-/epsilon-class GSTs and most likely evolved as an adaptation to tick blood-feeding life style. We have confirmed that IrGST1 expression is induced by dietary haem(oglobin), and not by iron or other components of host blood. Kinetic properties of recombinant IrGST1 were evaluated by model and natural GST substrates. The enzyme was also shown to bind haemin in vitro as evidenced by inhibition assay, VIS spectrophotometry, gel filtration, and affinity chromatography. In the native state, IrGST1 forms a dimer which further polymerises upon binding of excessive amount of haemin molecules. Due to susceptibility of ticks to haem as a signalling molecule, we speculate that the expression of IrGST1 in tick midgut functions as intracellular buffer of labile haem pool to ameliorate its cytotoxic effects upon haemoglobin intracellular hydrolysis.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10608 - Biochemistry and molecular biology

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

S - Specificky vyzkum na vysokych skolach<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Insect Biochemistry and Molecular Biology

ISSN

0965-1748

e-ISSN

—

Volume of the periodical

95

Issue of the periodical within the volume

APR 2018

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

44-54

UT code for WoS article

000440265600006

EID of the result in the Scopus database

2-s2.0-85045701301