Venom gland extract is not required for successful parasitism in the polydnavirus-associated endoparasitoid Hyposoter didymator (Hym. Ichneumonidae) despite the presence of numerous novel and conserved venom proteins

2013 ◽  
Vol 43 (3) ◽  
pp. 292-307 ◽  
Author(s):  
Tristan Dorémus ◽  
Serge Urbach ◽  
Véronique Jouan ◽  
François Cousserans ◽  
Marc Ravallec ◽  
...  
2010 ◽  
Vol 9 (4) ◽  
pp. 1882-1893 ◽  
Author(s):  
G. OmPraba ◽  
Alex Chapeaurouge ◽  
Robin Doley ◽  
K. Rama Devi ◽  
P. Padmanaban ◽  
...  

2021 ◽  
Author(s):  
Tarek Mohamed Abd El-Aziz ◽  
Yucheng Xiao ◽  
Jake Kline ◽  
Harold Gridley ◽  
Alyse Heaston ◽  
...  

The voltage-gated sodium channel Nav1.8 is linked to neuropathic and inflammatory pain, high-lighting the potential to serve as a drug target. However, the biophysical mechanisms that regu-late Nav1.8 activation and inactivation gating are not completely understood. Progress has been hindered by a lack of biochemical tools for examining Nav1.8 gating mechanisms. Arizona bark scorpion (Centruroides sculpturatus) venom proteins inhibit Nav1.8 and block pain in grasshopper mice (Onychomys torridus). These proteins provide tools for examining Nav1.8 structure-activity relationships. To identify proteins that inhibit Nav1.8 activity, venom samples were fractioned using liquid chromatography (reversed phase and ion exchange). A recombinant Nav1.8 clone expressed in ND7/23 cells was used to identify subfractions that inhibited Nav1.8 Na+ current. Mass spectrometry-based bottom-up proteomic analyses identified unique peptides from inhibi-tory subfractions. A search of the peptides against the AZ bark scorpion venom gland transcrip-tome revealed four novel proteins between 40 and 60% conserved with venom proteins from scorpions in four genera (Centruroides, Parabuthus, Androctonus, and Tityus). Ranging from 63 to 82 amino acids, each primary structure includes 8 cysteines and a CXCE motif where X = an aro-matic residue (tryptophan, tyrosine or phenylalanine). Electrophysiology data demonstrated that the inhibitory effects of bioactive subfractions can be removed by hyperpolarizing the channels, suggesting that proteins may function as gating modifiers as opposed to pore blockers.


Insects ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 29 ◽  
Author(s):  
Lei Yang ◽  
Beibei Wang ◽  
Liming Qiu ◽  
Bin Wan ◽  
Yi Yang ◽  
...  

Venom proteins act in the immunological interactions between parasitoids and their host insects. The effect of venom proteins on host immunity is not fully understood in pupal parasitoids. We identified the functions of a venom protein, calreticulin (PvCRT), in the pupal ectoparasitoid Pachycrepoideus vindemiae. Here, we report that PvCRT features a signal peptide and two conserved “calreticulin” domains. Multiple sequence alignments show that PvCRT shares 83.54% amino acid identity with CRT from both Pteromalus puparum and Nasonia vitripennis, which infers a close relationship among these three species. Using qPCR analysis, we found a lower expression level of PvCRT (0.27-fold) in the venom apparatus compared to the corresponding carcass. Immunohistochemical localization revealed that PvCRT was ubiquitously expressed in venom gland. The expression of the PvCRT gene in Drosophila transgenic lines via the UAS/Gal4 binary expression system reduced the self-encapsulation phenotype of tu(1)Sz1 mutants. Additionally, studies on humoral immunity indicate that PvCRT does not affect the antimicrobial immune responses of the host. This work on an ectoparasitoid will increase our understanding of venom–mediated host-parasitoid interactions.


Toxins ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 721 ◽  
Author(s):  
Rabia Özbek ◽  
Natalie Wielsch ◽  
Heiko Vogel ◽  
Günter Lochnit ◽  
Frank Foerster ◽  
...  

Within mega-diverse Hymenoptera, non-aculeate parasitic wasps represent 75% of all hymenopteran species. Their ovipositor dual-functionally injects venom and employs eggs into (endoparasitoids) or onto (ectoparasitoids) diverse host species. Few endoparasitoid wasps such as Pimpla turionellae paralyze the host and suppress its immune responses, such as encapsulation and melanization, to guarantee their offspring’s survival. Here, the venom and its possible biology and function of P. turionellae are characterized in comparison to the few existing proteo-transcriptomic analyses on parasitoid wasp venoms. Multiple transcriptome assembly and custom-tailored search and annotation strategies were applied to identify parasitoid venom proteins. To avoid false-positive hits, only transcripts were finally discussed that survived strict filter settings, including the presence in the proteome and higher expression in the venom gland. P. turionella features a venom that is mostly composed of known, typical parasitoid enzymes, cysteine-rich peptides, and other proteins and peptides. Several venom proteins were identified and named, such as pimplin2, 3, and 4. However, the specification of many novel candidates remains difficult, and annotations ambiguous. Interestingly, we do not find pimplin, a paralytic factor in Pimpla hypochondriaca, but instead a new cysteine inhibitor knot (ICK) family (pimplin2), which is highly similar to known, neurotoxic asilid1 sequences from robber flies.


Toxicon ◽  
2007 ◽  
Vol 50 (3) ◽  
pp. 383-393 ◽  
Author(s):  
Shivaiah Nagaraju ◽  
Sannaningaiah Devaraja ◽  
Kempaiah Kemparaju

1997 ◽  
Vol 48 (Supplement) ◽  
pp. 56
Author(s):  
K. Dezaki ◽  
Y. Kuraishi ◽  
K. Kamimura ◽  
T. Matsuse ◽  
M. Yoshida
Keyword(s):  

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