Interactions of Destruxin A with Silkworms’ Arginine tRNA Synthetase and Lamin-C Proteins

Abstract

Destruxin A (DA), a cyclodepsipeptidic mycotoxin produced by entomopathogenic fungus Metarhizium anisopliae, has good insecticidal activity and potential to be a new pesticide. However, the mechanism of action is still obscure. Our previous experiments showed that DA was involved in regulation of transcription and protein synthesis and suggested that silkworms’ arginine tRNA synthetase (BmArgRS), Lamin-C Proteins (BmLamin-C) and ATP-dependent RNA helicase PRP1 (BmPRP1) were candidates of DA-binding proteins. In this study, we employed bio-layer interferometry (BLI), circular dichroism (CD), cellular thermal shift assay (CETSA), and other technologies to verify the interaction of DA with above three proteins in vitro and in vivo. The results of BLI indicated that BmArgRS and BmLamin-C were binding-protein of DA with KD value 5.53 × 10−5 and 8.64 × 10−5 M, but not BmPRP1. These interactions were also verified by CD and CETSA tests. In addition, docking model and mutants assay in vitro showed that BmArgRS interacts with DA at the pocket including Lys228, His231, Asp434 and Gln437 in its enzyme active catalysis region, while BmLamin-C binds to DA at His524 and Lys528 in the tail domain. This study might provide new insight and evidence in illustrating molecular mechanism of DA in breaking insect.

Identification, Characterization, and Evaluation of Nematophagous Fungal Species of Arthrobotrys and Tolypocladium for the Management of Meloidogyne incognita

“…On the other hand, T. cylindrosporum Tc_RK also secreted non-volatile compounds with activity against nematodes, for instance, tolypocladenols, tolypyridone (A&B), and pyridoxatin, which were reported as metabolites from endolichenic isolate of T. cylindrosporum, Acremonium spp., and Trichoderma hamatum (Li et al, 2015;Romano et al, 2018). In addition to that, the tested isolate in the present study also secreted compounds such as terpendole E, 4-chloro-2-phenylphenol, destruxin A, and acetamido-6-anthraquinone, which were reported to have nematicidal activity (Ohri and Pannu, 2010;Ahn et al, 2013;Rogers et al, 2016;Shakeel et al, 2018;Wang et al, 2020) and not known to be present in T. cylindrosporum. It is also important to mention here that T. cylindrosporum Tc_RK isolated from dead C. elegans could be promising for nematode management due to its secretion of various novel metabolites with nematicidal properties.…”

Destruxin A Interacts with Aminoacyl tRNA Synthases in Bombyx mori

“…Owing to its special structure, cyclopeptide DA was proposed to interact with parts of ARSs in B. mori according to our preceding analysis; moreover, we intriguingly verified that arginyl tRNA synthetase (ArgRS) is a DA-binding-protein [14]. Here, we investigate the interactions between DA with six silkworm ARSs (BmAlaRS, BmCysRS, BmMetRS, BmValRS, BmIleRS, and BmGluProRS).…”

The Chemical Ecology Approach to Reveal Fungal Metabolites for Arthropod Pest Management

“…In vivo the hemocytes were more susceptible to DA at the extremely low dose of 0.25 µg/mL hemolymph [ 69 ]. Several silkworm proteins were found to bind DA, e.g., arginine tRNA synthetase and the stress support protein Lamin-C [ 70 ].…”