Molecular Characterization and Functional Analysis of the Nattectin-like Toxin from the Venomous Fish Thalassophryne maculosa

Abstract

TmC4-47.2 is a toxin with myotoxic activity found in the venom of Thalassophryne maculosa, a venomous fish commonly found in Latin America whose envenomation produces an injury characterized by delayed neutrophil migration, production of major pro-inflammatory cytokines, and necrosis at the wound site, as well as a specific systemic immune response. However, there are few studies on the protein structure and functions associated with it. Here, the toxin was identified from the crude venom by chromatography and protein purification systems. TmC4-47.2 shows high homology with the Nattectin from Thalassophryne nattereri venom, with 6 cysteines and QPD domain for binding to galactose. We confirm its hemagglutinating and microbicide abilities independent of carbohydrate binding, supporting its classification as a nattectin-like lectin. After performing the characterization of TmC4-47.2, we verified its ability to induce an increase in the rolling and adherence of leukocytes in cremaster post-capillary venules dependent on the α5β1 integrin. Finally, we could observe the inflammatory activity of TmC4-47.2 through the production of IL-6 and eotaxin in the peritoneal cavity with sustained recruitment of eosinophils and neutrophils up to 24 h. Together, our study characterized a nattectin-like protein from T. maculosa, pointing to its role as a molecule involved in the carbohydrate-independent agglutination response and modulation of eosinophilic and neutrophilic inflammation.

The perspective of fish venom: An overview of the physiology, evolution, molecular and genetics

“…Karatoxin 110kDa It is well known that fish venom is still largely unexplored as reported by (Silva et al, 2018;Xie et al, 2019;Gorman et al, 2020;Campos et al, 2021;Lopes-Ferreira et al, 2022) and in previous sections of this paper. Because there are few fish toxin sequences available as references, most of them are from Scorpaenidae and Synanceiidae families, it is challenging to research fish toxins and to create quick and effective techniques for wide exploration of toxin proteins or genes (Xie et al, 2017).…”

“…Because there are few fish toxin sequences available as references, most of them are from Scorpaenidae and Synanceiidae families, it is challenging to research fish toxins and to create quick and effective techniques for wide exploration of toxin proteins or genes (Xie et al, 2017). Some recent studies have isolated and provided several toxins sequences using different techniques (Smith and Wheeler, 2006;Xie et al, 2016;Costa et al, 2018;Xie et al, 2019;Campos et al, 2021;Lopes-Ferreira et al, 2022), but due to a given number of venomous fish (>2000 species) (Saggiomo et al, 2021), it would be just a small portion of it.…”

“…However, this method takes a long time and uses a lot of crude venoms. Studies have shown, cDNA cloning and genomic sequencing were used to identify the full amino acids sequences of various toxins including SNTX (Chun, 2004), verrucotoxin (VTX) (Ziegman and Alewood, 2015), cytolysins (Campos et al, 2021), lectin (Nakagawa et al, 2015;Ziegman et al, 2019;Lopes-Ferreira et al, 2022), Sp-CTx (Costa et al, 2018), and hyaluronidases (Ziegman et al, 2019) and among the others in which most of them exhibit high sequence identity among and between species.…”

“…Currently, fewer venomous fish species have undergone transcriptome and proteome research. A ray species, catfish species, and fang blenny species are among those for whom there are comparable proteomic data (Xie et al, 2017;Xie et al, 2019;Lopes-Ferreira et al, 2022). Recently, expressed sequence tags were used to analyze the venom gland transcripts of toadfish (Ziegman and Alewood, 2015).…”

Celebrating 120 Years of Butantan Institute Contributions for Toxinology

“…The venom of snakes was approached in different aspects as the structural and functional variability in the composition of venoms from individual snakes [1], the mechanisms of action of whole venoms [2,3], the mechanisms of action of individual components as crotoxin [4], phospholipases A2 [5], metalloproteinases [6][7][8], and the oral immunity induced by whole venoms and their components [9]. Venoms from other animals are also reported; the venoms of centipedes [10], scorpions [11,12], fishes [13,14], and caterpillars [15], including microbial toxins [16]. The great potential for molecules derived from animal venoms as drug leads was also reviewed [17], and the antimicrobial [18], anticoagulant [19,20], and analgesic [21,22] effects have been highlighted in original studies reported here.…”