Identification of an in vitro interaction between an insect immune suppressor protein (CrV2) and G alpha proteins

Cooper, Tamara H., Bailey-Hill, Kelly, Leifert, Wayne R., McMurchie, Edward J., Asgari, Sassan and Glatz, Richard V. (2011) Identification of an in vitro interaction between an insect immune suppressor protein (CrV2) and G alpha proteins. Journal of Biological Chemistry, 286 12: 10466-10475. doi:10.1074/jbc.M110.214726

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
UQ247158_OA.pdf Full text (open access) application/pdf 1.51MB 0

Author Cooper, Tamara H.
Bailey-Hill, Kelly
Leifert, Wayne R.
McMurchie, Edward J.
Asgari, Sassan
Glatz, Richard V.
Title Identification of an in vitro interaction between an insect immune suppressor protein (CrV2) and G alpha proteins
Formatted title
Identification of an in vitro interaction between an insect immune suppressor protein (CrV2) and Gα proteins
Journal name Journal of Biological Chemistry   Check publisher's open access policy
ISSN 0021-9258
1083-351X
1067-8816
Publication date 2011-03-01
Sub-type Article (original research)
DOI 10.1074/jbc.M110.214726
Open Access Status File (Publisher version)
Volume 286
Issue 12
Start page 10466
End page 10475
Total pages 10
Place of publication Bethesda, MD, U.S.A.
Publisher American Society for Biochemistry and Molecular Biology
Language eng
Formatted abstract
The protein CrV2 is encoded by a polydnavirus integrated into the genome of the endoparasitoid Cotesia rubecula (Hymenoptera:Braconidae:Microgastrinae) and is expressed in host larvae with other gene products of the polydnavirus to allow successful development of the parasitoid. CrV2 expression has previously been associated with immune suppression, although the molecular basis for this was not known. Here, we have used time-resolved Förster resonance energy transfer (TR-FRET) to demonstrate high affinity binding of CrV2 to Gα subunits (but not the Gβγ dimer) of heterotrimeric G-proteins. Signals up to 5-fold above background were generated, and an apparent dissociation constant of 6.2 nM was calculated. Protease treatment abolished the TR-FRET signal, and the presence of unlabeled CrV2 or Gα proteins also reduced the TR-FRET signal. The activation state of the Gα subunit was altered with aluminum fluoride, and this decreased the affinity of the interaction with CrV2. It was also demonstrated that CrV2 preferentially bound to Drosophila Gαo compared with rat Gαi1. In addition, three CrV2 homologs were detected in sequences derived from polydnaviruses from Cotesia plutellae and Cotesia congregata (including the immune-related early expressed transcript, EP2). These data suggest a potential mode-of-action of immune suppressors not previously reported, which in addition to furthering our understanding of insect immunity may have practical benefits such as facilitating development of novel controls for pest insect species.
Keyword Cotesia-plutellae bracovirus
Heterotrimeric G-protein
Transient expression
Hemocyte inactivation
Antimicrobial peptide
Rubecula bracovirus
Galleria-mellonella
Endoparasitoid wasp
Polydnavirus genese
Spreading behavior
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: Official 2012 Collection
School of Biological Sciences Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 9 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 10 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Tue, 06 Sep 2011, 01:21:42 EST by Gail Walter on behalf of School of Biological Sciences