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Venom from the Araneus ventricosus is lethal to insects but inactive in vertebrates

Liu, K; Wang, M; Herzig, Volker; et.al. https://research.usc.edu.au/discovery/delivery/61USC_INST:ResearchRepository/12126644270002621?l#13129823260002621

Liu, K., Wang, M., Herzig, V., Liu, Z., Hu, W., Zhou, G., & Duan, Z. (2016). Venom from the spider Araneus ventricosus is lethal to insects but inactive in vertebrates. Toxicon, 115, 63–69. https://doi.org/10.1016/j.toxicon.2016.03.010 Document Type: Accepted Version

Link to Published Version: https://doi.org/10.1016/j.toxicon.2016.03.010

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Please do not remove this page Accepted Manuscript

Venom from the spider Araneus ventricosus is lethal to insects but inactive in vertebrates

Kai Liu, Meichi Wang, Volker Herzig, Zhen Liu, Weijun Hu, Guihua Zhou, Zhigui Duan

PII: S0041-0101(16)30050-2 DOI: 10.1016/j.toxicon.2016.03.010 Reference: TOXCON 5333

To appear in: Toxicon

Received Date: 3 December 2015 Revised Date: 26 February 2016 Accepted Date: 15 March 2016

Please cite this article as: Liu, K., Wang, M., Herzig, V., Liu, Z., Hu, W., Zhou, G., Duan, Z., Venom from the spider Araneus ventricosus is lethal to insects but inactive in vertebrates, Toxicon (2016), doi: 10.1016/j.toxicon.2016.03.010.

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Venom from the spider Araneus ventricosus is lethal to insects but inactive in vertebrates

Kai Liu 1, Meichi Wang 1, Volker Herzig 2, Zhen Liu 1, Weijun Hu 1, Guihua, Zhou 4, Zhigui Duan 1, 3, *

1, The Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education,

College of Life Sciences, Hunan Normal University, Changsha, Hunan, 410081, China

2, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Qld 4072, Australia

3, National Experiment Teaching Demonstration Center of General Biology, College of Life Sciences,

Hunan Normal University, Changsha, Hunan, 410081, China

4, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan,

410081, China

* Corresponding author The Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, P.R. China. Tel: +86-0731-8872556 MANUSCRIPT Fax: +86-0731-8861304 E-mail:[email protected]

Abbreviations DRG, dorsal root ganglion DUM neurons, dorsal unpaired median neurons HEPES, N-hydroxyethyl piperazine-N-ethanesulfonic acid; LD50, median lethal dose. MALDI-TOF,ACCEPTED Matrix assisted laser desorption/ionization-time of flight; RP-HPLC, Reverse Phase - High Performance Liquid Chromatography; SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electropheresis; VGSCs, Voltage-gated sodium channels

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Abstract

Araneus ventricosus spider venom, which was collected by electrical stimulation, is abundant in peptides and proteins with molecular weights ranging from 2 kDa to 70 kDa as determined by gel electrophoresis and mass spectrometry.

Electrophysiological experiments showed that 50 µg/mL venom could block the voltage-gated sodium channels (VGSCs) currents of the dorsal unpaired median

(DUM) neurons of Periplaneta americana cockroaches. However, 500 µg/mL venom could not block the VGSCs currents in rat dorsal root ganglion cells or the neuromuscular transmission in isolated mouse phrenic nerve-hemidiaphragm.

Moreover, we also observed that injection of the venom in P. americana gave rise to obvious envenomation symptoms, with a LD 50MANUSCRIPT value of 30.7 µg/g. Enzymatic analysis indicated that the venom possessed activities of several kinds of hydrolases including hyaluronidase and proteases. These results demonstrate that A. ventricosus venom contains bioactive components targeting insects, which are the natural prey of these . Furthermore, the venom was found to be not active in vertebrate. Thus, we suggest that A. ventricosus venom contains novel insect-selective compounds that might be helpful in developing new and safe insecticides.

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Keywords: Araneus ventricousus , venom composition, electrophysiological analysis, voltage-gated sodium channels (VGSCs).

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1. Introduction

In order to capture prey or defend themselves, spiders have developed potent

neurotoxins and other biologically active compounds in their venom. Spider venoms

are complex mixtures of biologically active compounds, from salts to large

multidomain proteins (Schanbacher et al., 1973; Ori et al., 1998; Vassilevski 2009

Kuhn-Nentwig et al., 2011). The extraordinary chemical and pharmacological complexity of spider venoms has encouraged many scientists to systematically analyze these venoms in an attempt to unveil candidates for drug and pesticide discovery (Windley et al., 2011 & 2012), and as well as tools to study important receptors and ion channels (King, 2011). With spiders being the most successful insect predators on this planet, it seems logical MANUSCRIPT that the majority of spider venom compounds are insecticidal. As far as the pharmacology and biochemistry of spider venom is concerned, spider venom contains a wide variety of ion channel toxins, novel non-neurotoxins, enzymes and low molecular weight compounds (Adams, 2004;

Ushkaryov et al., 2004; Kuhn-Nentwig et al., 2004; Escoubas et al., 2000&2004;

Liang, 2004; Li et al., 2005; Duan et al., 2008; King & Hardy 2013).

Up to the present, there are 45,841 described spiders (World Spider Catalog

2016), with ACCEPTED an even greater number awaiting characterization (Coddington, 1991).

Despite this diversity, peptide toxins have so far been studied from the venom of only

97 spider species (Herzig et al., 2011). Within the Araneus , only the venoms of few species have been studied, such as Araneus gemma and Araneus diadematus ,

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ACCEPTED MANUSCRIPT which were reported to target glutamate receptors from vertebrates, insects or crustaceans (Usherwood et al., 1984; Michaelis et al., 1984; Vyklický et al., 1986).

The nocturnal spider A. ventricosus belonging to genus Araneus are found in Russia,

China, Korea, Taiwan, and Japan (World Spider Catalog 2016). Spiders of the genus

Araneus mainly feed on flies, mosquitos, and other invertebrates. Their venom is a

complex mixture of components with diverse biological actions that can rapidly

paralyze and kill insects. Although some studies have described bioactivies of venom

from A. ventricosus antagonizing the glutamate receptor and killing the silkworm

larvae (Kawai et al., 1983; Chung et al., 2002), a systematic physiological and

biochemical analysis of the venom has not been available.

In the present study, we have therefore examined the composition and activity of A. ventricosus (Fig. l) venom in more detail, MANUSCRIPT using chromatographic as well as electrophysiological techniques. Furthermore, the enzymatic activity of the venom

was examined and its bioactivity determined by injection into cockroaches and mice.

Electrophysiological analysis revealed that A. ventricosus venom showed insecticidal

activity due to venom components targeting voltage-gated sodium channels (VGSCs)

in cockroach dorsal unpaired median (DUM) neurons, which has been well

acknowledged as a useful tool for the identification of novel insecticides (Wang et al.,

2012; GrolleauACCEPTED et al., 2000; King, 2011, King & Hardy 2013). Furthermore, we did neither observe any envenomation symptoms when injecting this venom into mice, nor any activity on rat dorsal root ganglion (DRG) neurons or in the mouse phrenic nerve-hemidiaphragm preparation. It can therefore be concluded that A.ventricosus

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ACCEPTED MANUSCRIPT venom contains insecticidal compounds, which seem to be devoid of any vertebrate activity.

MANUSCRIPT

Fig. 1. Araneus ventricosus .

2. Materials and methods

2.1 Chemicals

Trifluoroacetic acid (TFA), dithiothreitol (DTT), iodoacetamide (IAA), acrylamide, ACCEPTED N, N'-methylene bisacrylamide (Bis), Glycine, trihydroxymethyl aminomethane (Tris), sodium dodecyl sulfate (SDS) and SDS-PAGE protein standards were purchased from Bio-Rad Laboratories (Hercules, CA, USA).

Bromophenol blue, N, N, N’, N’-tetramethylethylenediamine (TEMED) were

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ACCEPTED MANUSCRIPT obtained from Amersham Pharmacia Biotech (Uppsala, Sweden).

Phenylmethylsulfonyl fluoride (PMSF) was from Ameresco. HPLC-grade acetonitrile

(ACN) was purchased from Hunan Fine Chemistry Institute (Hunan, China). Casein, cetyltrimethylammonium bromide, hyaluronate were from Sangon biotech Co., Ltd.

Acetylcholinesterase, Alkaline phosphatase and Acid phosphatase kit were from

Nanjing jiancheng bioengineering institute (China).

2.2 Venom collection

Spiders captured in the wild were used for venom extraction. The venom was collected from female spider A. ventricosus using a method described in our previous

study (Wang et al, 2007), then the venom was freeze-dried and stored at -80 °C before analysis. MANUSCRIPT

2.3 Enzyme activity and Protein analysis

The determination of hydrolase hyaluronidase (Ferrante, 1956), proteinase (Rich,

1963), alkaline phosphatase (Bessey et al., 1946), acid phosphatase (Bessey et al.,

1946) and acetylcholine esterase (Pilz, 1963) were performed according to the methods described previously. Protein content of the venom was determined using

Bradford methodACCEPTED (Bradford, 1976). SDS-PAGE of the venom was performed according to the method of Laemmli (Laemmli 1970) under denatured conditions in a

14% polyacrylamide slab gel. Venom sample (12 µg) was denatured and reduced in

SDS loading buffer and boiled for 3 min. The venom solution was centrifuged for 10

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ACCEPTED MANUSCRIPT min at room temperature (25°C) and 10,000 g, then the supernatant was loaded into the gel well. SDS-PAGE was run at 25 mA on polyacrylamide stacking gel and at 50 mA on separating gel. After completion of electrophoresis, the proteins in gel were visualized by Coomassie Brilliant Blue G-250. The low molecular weight calibration

Kit (Fermentas, USA) was used as standard molecular weight marker proteins.

2.4 Toxin purification with RP-HPLC

The crude venom was analyzed on a reversed-phase C4 column (4.6mm×250mm,

Sepax Technologies, USA) using a Waters HPLC Alliance system (Waters, USA) with

a 996 photodiode array detector. Mobile phase A was 0.1% aqueous TFA and mobile

phase B was acetonitrile containing 0.1% TFA. After the sample was loaded, components were eluted for 60 min with the MANUSCRIPT following gradient of solvent B: 0-22 min, 0-20%; 22-26 min, 20-40%; 26-56 min, 40-80%. Flow rate was maintained at

0.7 mL/min, and effluent absorbance was recorded at 280 nm. Eluates were respectively collected and lyophilized, stored at -20°C.

2.5 Mass spectrometric analysis

Mass spectrometry was used to detect the peptides or proteins with molecular weight belowACCEPTED 20 kDa . The analysis was performed in AB Sciex-TOF/TOF 5800 mass spectrometer (Applied Biosystems, USA) by choosing the matrix α

-Cyano-4-hydroxycinnamic acid (CHCA) (Sigma-Aldrich, USA), 0.5 L (10 mg/mL) mixed with 0.5 L venom sample (20 g/mL). Mass spectra were recorded under the

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ACCEPTED MANUSCRIPT control of TOF/TOF series explorer software (Applied Biosystems, USA).

MALDI-TOF spectra were recorded in the positive ion linear mode over a mass range of 1000-20000 Da. Linear final detector voltage was 1.92 kV. Laser intensity was

3800. An external mass calibration was done daily.

2.6 Electrophysiological studies

2.6.1 Acute isolation and primary culture of neurons

DRG neurons were acutely dissociated from 30-day old Sprague–Dawley rats and maintained in short-term primary culture according to the method described by Xiao and Liang (2003). Briefly, the DRG were removed quickly from the spinal cord with ophthalmic forceps after a quick death by decapitation. With all the ganglia cut into smaller tissues as possible, they were transferred MANUSCRIPT into Dulbecco’s modified Eagle’s medium (DMEM) containing trypsin (0.5 mg/ml, type III, Sigma), Collagenase (1.0 mg/ml, type IA, Sigma) then incubated at 37 °C with gentle agitation for 30 min.

Trypsin inhibitor (1.5 mg/mL, type II-S, Sigma, USA) was used to terminate enzyme treatment. After transfer into 35 mm culture dishes (Corning, Sigma), coated with 1 mg/mL poly-L-lysine (Sigma), the DRG cells were incubated for 2–4 h before patch-clamp experiment.

DUM neuronsACCEPTED were acutely isolated from the adult cockroach based on our

previous method (Wang et al., 2012). Briefly, abdominal ganglia from adult cockroach

(P. americana ) were desheathed, then incubated in insect physiological solution (in mM): 90 NaCl, 6 KCl, 2 CaCl2, 2 MgCl2, and 10 HEPES, 140 glucose, pH 6.6

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ACCEPTED MANUSCRIPT containing 1 mg/ml trypsin for 5 min. Following this procedure, the ganglia were removed and stored in physiologic solution for 1 h to restore. The large DUM cells situated in the dorsal midline of the ganglia were separated using thin silver needles.

The cell viability was assessed by microscopic observation: only those cells, which appeared bright under phase contrast microscope were used.

2.6.2 Patch clamp electrophysiology

For VGSC currents recording, the pipette solution for rat DRG neurons

. contained (in mM): CsCl 145, MgCl 2 6H 2O 4, HEPES 10, EGTA 10, D-Glucose 10,

ATP 2 (pH 7.2), and the external solution contained (in mM): NaCl 145, KCl 2.5,

. CaCl 2 1.5, MgCl 2 6H 2O 1.2, HEPES 10, D-Glucose 10 (pH 7.4). The external solution for insect dorsal unpaired median neurons contained MANUSCRIPT (in mM): 80 NaCl, 30 TEA-Cl, 2 CaCl 2, 4 KCl, 10 HEPES, 10 glucose, 50 choline-Cl, and 1 4-AP (pH 6.8), and the micropipette internal solution for these neurons contained (in mM): 140 CsF, 2 MgCl 2,

10 EGTA, and 10 HEPES (pH 6.8). All experiments were conducted at room

temperature (22–25°C). Suction pipettes (2.0–4.0 M) were prepared using borosilicate glass capillary tubes with a two-step pulling on a vertical micropipette puller. To eliminate the influence of differences in osmotic pressure, all internal and external solutionsACCEPTED were adjusted to 280 ± 5 mosmol/L with sucrose. Experimental

data were collected and analyzed using the program Pulse/Pulsefit 8.0 (HEKA

Electronics, Germany) and Sigmaplot 10.0. Macroscopic currents were filtered at 10

kHz and digitized at 3 kHz with an EPC-10 patch-clamp amplifier (HEKA Electronics,

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Germany). Series resistance was maintained near 5 M and compensated 65–70%.

Linear capacitative and leakage currents were digitally subtracted using the P/4 protocol. All data are presented as means ± S.E., and n is the number of

independent experiments.

2.6.3 Effects of venom on the mouse phrenic nerve-hemidiaphragm preparation

The experiments were carried out using mouse isolated phrenic

nerve-hemidiaphragm preparations (Zhou et al., 1997). Adult Kunming albino mice

were sacrificed by CO 2 overdose followed by cervical dislocation. After dissection,

the preparation was placed in a small Plexiglas chamber and immersed in Tyrode’s

solution with or without venom, bubbled with 95% O 2/ 5%CO 2/ pH7.4 and kept at 32 °C. Electrical stimulation was applied to theMANUSCRIPT phrenic nerve with a suction electrode (supramaximal voltage, 2 ms duration, square wave). The twitch responses were transformed into an electric signal by a mechanical-electric transducer. Signals were amplified and recorded with signal process system (Model Biolap 98, China).

2.7 Toxicity of the crude venom

LD 50 determination in P. americana cockroaches was performed according to the methods describedACCEPTED by Schweitz (1984) and Liang et al. (1993). Fifty-six cockroaches were randomly divided into 9 groups. Eight groups were used as experimental groups to which 10 L of venom solution was injected between the fourth and fifth sternites as single doses of 8.125, 11.7, 16.84, 24.25, 34.89, 50.24, 72.34 or 104.17 g/g. The

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ACCEPTED MANUSCRIPT ninth group was used as control and injected with insect physiological saline.

Lethality in P. americana was observed 24 h after injection. The LD 50 values were determined based on the lethality in six at each dose level (Liang et al., 1993).

3 Results and Discussion

3.1 Venom composition

Although the venom of A. ventricosus has been reported to contain glutamate receptor antagonists and compounds that are lethal to silkworm larvae (Kawai et al.,

1983; Chung et al., 2002), the composition and properties of the venom have not been fully explored. To gain a better understanding of the protein and peptide constituents of this spider venom, we have therefore used electrophoresis, chromatography, and mass spectrometry. A. ventricosus spiders yielded MANUSCRIPT between 2-8 L of venom and the venom density was 1036.5 g/ L. The quantitative determination indicated that the

protein content of the venom was 22.4 % (Table 1) based on the lyophilized venom,

which is lower than that of many other spiders such as H. huwenum (77.4 %) (Liang et al., 1993) and L. tredecimguttatus (55%) (Wang et al., 2007). This implies that the

content of non-proteins is relatively high compared with the venom of other spiders of

such as black widow spiders (Wang et al., 2007). In the SDS-PAGE gel of the venom,

the main venomACCEPTED protein bands are distributed in the range of 10 to 45 kDa (Fig. 2).

The highest abundance of protein bands was at around 10 to 20 kDa, 26 kDa and 43

kDa. There were fewer proteins above 45 kDa. Given that SDS-PAGE gels are incapable of resolving small molecular weight peptides, other than the fact that

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ACCEPTED MANUSCRIPT peptides < 10 kDa are definitely present in A. ventricosus venom, we cannot make any further conclusions about their abundance based the present results. Our previous study further indicated that most venom proteins of A. ventricosus are alkaline proteins (Duan et al., 2013) with molecular masses in the range of 10-45 kDa (Fig. 2), which is also different from black widow spider (Duan et al., 2008).

Table 1 Properties of Araneus vetricosus spider venom

Item Determined Value*

Wet venom yield 2-8 L/spider

Venom density 1036.5 g/ L

Dried venom yield 214.9 g/ L Protein content MANUSCRIPT 22.4 % LD 50 value in cockroach 30.7 g/g

Hyaluronidase activity 0.412 U/mg

Alkaline phosphatase activity 5.1×10 -3 U/mg

Acid phosphatase activity 6.2×10 -3 U/mg

Choline esterase activity 1.2×10 -3 U/mg

Protease activity 5.8 U/mg ACCEPTED *Protein content and enzymatic activities are expressed based on dried venom; LD 50 values are expressed based on body weight.

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Fig. 2. SDS-PAGE (14%) gel image of A. ventricosus venom. (10 g) in lane B, compared to the standard molecular weight ladder in lane A.

MANUSCRIPT

Fig. 3. HPLC profile of A. ventricosus venom using a C4 column with varying percentage of acetonitrile as indicated on the right y-axis. ACCEPTED

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Fig. 4. MALDI-TOF MS profile of A. ventricosus venom.

Using a C4 reverse phase column, we obtained about 30 elution peaks by

RP-HPLC (Fig. 3). The chromatogram showed that there were two main fractions, one was distributed in about 4-22 min, corresponding to about 2-18% (v/v) acetonitrile , and the other was about 27-34 min, corresponding to about 41-51% (v/v) acetonitrile .

In order to get more information about the composition of the A. ventricosus venom, MANUSCRIPT we used MALDI-TOF MS, which showed that the main peptide components of the venom were distributed in the range of 2000-12000 m/z, with several predominant components at m/z values of 3347.1914, 4452.7612, 5696.5645, 5179.1284, 6690.194,

8209.7510 and 11387.123 respectively (Fig. 4). These results demonstrate that the diversity of components present in A. ventricosus venom.

3.2 BioactivityACCEPTED of the crude venom A. ventricosus are orb-weaving spiders and therefore mainly localized on their net.

They have nocturnal habits and their nets are often found in places that have a large

abundance of flying insects such as in pigsties and under eaves and fencing. They can be helpful in controlling pests in the home, garden or farmland. Injection of A.

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ACCEPTED MANUSCRIPT ventricosus venom into P. americana cockroaches causes immediate envenomation symptoms, including flaccid paralysis, lethargy and ataxia. Moreover, the highest dose

(104.17 g/g) that we tested led to a quick death. These results indicate that the venom contains components toxic to insects, which is agreement with previous data

(Kawai et al., 1983). The LD 50 value in P. americana was 30.73 g/g body weight

(Table 1), which was much lower than that of other spiders venom, such as H.

huwenum (300 µg/g) (Liang et al., 1993) and D. mizhoanus (56.2 µg/g) (Li et al.,

2014), two spiders that can prey on vertebrates.

The results for the enzymatic activities of the venom are listed in Table 1. The

venom possesses enzymatic activities such as hyaluronidase, alkaline phosphatase,

acid phosphatase, choline esterase and protease. These enzymatic activities will participate in the desctruction of prey tissues MANUSCRIPT (Kuhn-Nentwig et al., 2011), which facilitates the spread of toxins in envenomated prey.

Biting incidents that happened during the collection of A. ventricosus venom did not produce any obvious symptoms except for mechanical injury, and injection into mice at 100 mg/kg venom did not cause any toxic symptoms (data not shown).

Furthermore, the experiment indicated that the venom could not block neuromuscular transmission in the mouse phrenic nerve-hemidiaphragm preparation at doses up to 1 mg/mL (Fig.ACCEPTED 5), while L. tredecimguttatus venom (6 g/mL) was reported to significantly block the neuromuscular transmission (Wang et al., 2007). In summary, our results suggest that A. ventricosus venom contains components selectively targeting insects without affecting vertebrates. In comparison, the venom of most

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ACCEPTED MANUSCRIPT other spiders, such as Haplopelma schmidti (formerly H. huwenum ), and Latrodectus tredecimguttatus , are active against both insects and vertebrates. (Liang et al., 1993;

Wang et al., 2007).

Fig. 5. Effect of venom on isolated mouse phrenic nerve-hemidiaphragm preparation. Venom was added (at 1 mg/mL) after achieving stable contraction in venom-free Krebs solution.

3.3 Electrophysiological effects on VGSCs of DRG and DUM neurons

VGSCs participate mainly in the rapid depolarization phase of action potential (Klint

et al., 2012; Catterall, 2014). Most venomous animals have developed efficient toxins targeting VGSCs for defense or prey capture. MANUSCRIPT Toxins acting on VGSCs could potentially be used as a lead for the development of novel insecticides (Nicholson,

2007; Windley et al., 2012). It is well known that many agrochemical insecticides,

such as DDT, N-alkylamines and pyrethroids (Sattelle et al.,1988; Soderlund et al.,

1989; Narahashi et al., 1998; Raymond-Delpech et al., 2005; Nicholson, 2007.) target

VGSCs.

ACCEPTED

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Fig. 6. Different effects on VGSCs of DRG and DUM neurons. All inward current traces were elicited by a 50 ms depolarizing MANUSCRIPT potential of 0 mV from a holding potential of -80 mV every 5 s. (A). Typical traces in the absence or presence of 500 µg/mL A. ventricosus venom on VGSCs of DRG neurons. (B). Typical traces in the absence or presence of 50 µg/mL A. ventricosus venom on VGSCs of DUM neurons. (C). Concentration-dependent inhibition of VGSC currents in DUM neurons by A. ventricosus venom. Each data point (mean ± SE) shows the current as a fraction of the control current (n = 5). Data were fitted with a Boltzmann equation to yield an IC 50 value of 19.8 ± 0.1 g/mL. (D). Normalized currents induced before (control) and 5 mins after 20 µg/mL of A. ventricosus venom application. Cells were held at -80 mV and sodium ACCEPTEDcurrents were induced by 50 ms depolarizing steps to various potential ranging from -80 mV to +60 mV in 10 mV increments. Data are mean ± S.E

As shown in Fig. 6B, A. ventricosus venom blocks the conductance of VGSCs on

DUM neurons, with an IC 50 of 19.8 ± 0.1 g/mL (Fig. 6C). 50 µg/mL venom 17

ACCEPTED MANUSCRIPT completely blocked the currents. Interestingly, there were no effects observed on

VGSCs of rat DRG neurons with doses as high as 500 µg/mL (Fig. 6A). For DUM neurons, the blockade of VGSC conductance was not voltage-dependent (Fig. 6D), which implies that the components targeting VGSCs in this venom may act as pore blockers, not gating modifiers. These results explain why A. ventricosus spider venom produced such potent lethal effects to cockroaches, while being inactive in mice. This data therefore provides evidence for the presence of venom compounds that selectively target insects. We therefore suggest that this venom could be a promising source of novel bioinsecticides. Furthermore, our data indicate that some A. ventricosus venom components might be helpful tools to understand the mechanism for the phyletic specificity of toxins being active in insects but not in vertebrates. Such knowledge on the phyletic specificity MANUSCRIPT of venom components would be very valuable for the development of novel and safe bioinsecticides (Bende et al., 2014).

Conclusion

The present results demonstrate that A. ventricosus venom selectively blocks

VGSCs currents of cockroach DUM neurons but not rat DRG neurons. Thus, A. ventricosus venom appears to be a promising source of novel and safe bioinsecticides.

ACCEPTED

Acknowledgements

This work was supported by the National Natural Science Foundation of China

(31402025) and the Youth Foundation of Hunan Normal University (090640) and the

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Cooperative Innovation Center of Engineering and New Products for Developmental Biology of

Hunan Province (No. 20134486) and the National Natural Science Foundation of China

(31201718).

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 Venom from the spider Araneus ventricosus is selectively target insects without

affecting vertebrates

 Araneus ventricosus venom selectively blocks VGSCs currents of cockroach

DUM neurons but not rat DRG neurons

 Araneus ventricosus venom appears to be a promising source of novel and safe

bioinsecticides.

MANUSCRIPT

ACCEPTED ACCEPTED MANUSCRIPT Ethical Statement

The use and care of animals in this study follow the guidelines of the Institutional Care and Use Committee of Hunan province.

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