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Andrés Taucare-Ríos, Gustavo Bizama, Ramiro O Bustamante
The brown widow spider, Latrodectus geometricus C. L. Koch, 1841, is a large spider of the family Theridiidae that belongs to a genus of medical interest owing to its potent neurotoxic venom, which causes severe pain in humans. In America, this alien spider has been found in virtually all countries in the region, mainly associated with human dwellings, but also in agricultural sectors. However, the invasive process and potential distribution of this invasive species across the American continent are completely unknown...
December 2016: Environmental Entomology
Dehong Xu, Xianchun Wang
Latrodectus tredecimguttatus is a kind of highly venomous black widow spider, with toxicity coming from not only venomous glands but also other parts of its body as well as newborn spiderlings and eggs. Up to date, although L. tredecimguttatus eggs have been demonstrated to be rich in proteinaceous toxins, there is no systematic investigation on such active components at transcriptome level. In this study, we performed a high-throughput transcriptome sequencing of L. tredecimguttatus eggs with Illumina sequencing technology...
December 20, 2016: Toxins
Alexandra Rueda, Emilio Realpe, Alfredo Uribe
The genus Latrodectus has not been studied in Colombia even though it is medically important worldwide; there are three species for the country, this study focused on a non-identified species found in the Tatacoa Desert in the Huila Department. This research is the first approximation to the extraction, composition analysis and toxicity evaluation of the venom of a species of the genus Latrodectus in Colombia; and aims to evaluate the toxicity by the initial characterization of its venom. The venom extraction was accomplished with electrostimulation and total protein concentration was determined by the Lowry method and BCA assays from crude venom; with these methods, high protein concentration of the samples was measured...
January 2017: Toxicon: Official Journal of the International Society on Toxinology
I Corral-Corral, C Corral-Corral
INTRODUCTION: Tarantism is the disease caused by the bite of the tarantula, in which the music tarantella triggers an involuntary dance. It is known in Italy since the sixteenth century. AIM: To analyze the tarantism reported in Spain at the end of the eighteenth century, with special attention to its neurological aspects, and to propose its medical and psychopathological explanation. DEVELOPMENT: An epidemic of people affected by the tarantula bite occurred in Spain in 1782...
October 16, 2016: Revista de Neurologia
Joschka Bauer, Daniel Schaal, Lukas Eisoldt, Kristian Schweimer, Stephan Schwarzinger, Thomas Scheibel
Dragline silk is the most prominent amongst spider silks and comprises two types of major ampullate spidroins (MaSp) differing in their proline content. In the natural spinning process, the conversion of soluble MaSp into a tough fiber is, amongst other factors, triggered by dimerization and conformational switching of their helical amino-terminal domains (NRN). Both processes are induced by protonation of acidic residues upon acidification along the spinning duct. Here, the structure and monomer-dimer-equilibrium of the domain NRN1 of Latrodectus hesperus MaSp1 and variants thereof have been investigated, and the key residues for both could be identified...
September 29, 2016: Scientific Reports
M Daniela Biaggio, Iara Sandomirsky, Yael Lubin, Ally R Harari, Maydianne C B Andrade
Copulatory cannibalism of male 'widow' spiders (genus Latrodectus) is a model example of the extreme effects of sexual selection, particularly in L. hasselti and L. geometricus where males typically facilitate cannibalism by females and mate only once. We show that these males can increase their reproductive success by copulating with final-instar, immature females after piercing the female's exoskeleton to access her newly developed sperm storage organs. Females retain sperm through their final moult and have similar fecundity to adult-mated females...
September 2016: Biology Letters
Andrés Taucare-Ríos, Gustavo Bizama, Ramiro O Bustamante
The brown widow spider, Latrodectus geometricus C. L. Koch, 1841, is a large spider of the family Theridiidae that belongs to a genus of medical interest owing to its potent neurotoxic venom, which causes severe pain in humans. In America, this alien spider has been found in virtually all countries in the region, mainly associated with human dwellings, but also in agricultural sectors. However, the invasive process and potential distribution of this invasive species across the American continent are completely unknown...
September 17, 2016: Environmental Entomology
Sean J Blamires, Michael M Kasumovic, I-Min Tso, Penny J Martens, James M Hook, Aditya Rawal
The exceptional strength and extensibility of spider dragline silk have been thought to be facilitated by two spidroins, major ampullate spidroin 1 (MaSp1) and major ampullate spidroin 2 (MaSp2), under the assumption that protein secondary structures are coupled with the expressed spidroins. We tested this assumption for the dragline silk of three co-existing Australian spiders, Argiope keyserlingi, Latrodectus hasselti and Nephila plumipes. We found that silk amino acid compositions did not differ among spiders collected in May...
August 9, 2016: International Journal of Molecular Sciences
Samantha Vibert, Catherine Scott, Gerhard Gries
Web-building spiders construct their own vibratory signaling environments. Web architecture should affect signal design, and vice versa, such that vibratory signals are transmitted with a minimum of attenuation and degradation. However, the web is the medium through which a spider senses both vibratory signals from courting males and cues produced by captured prey. Moreover, webs function not only in vibration transmission, but also in defense from predators and the elements. These multiple functions may impose conflicting selection pressures on web design...
November 2016: Journal of Comparative Physiology. A, Neuroethology, Sensory, Neural, and Behavioral Physiology
Elham Valikhanfard-Zanjani, Abbas Zare-Mirakabadi, Shahrbanoo Oryan, Hamid Reza Goodarzi, Mahdise Rajabi
BACKGROUND: Latrodectism, a syndrome caused by Latrodectus genus, is one of the clinical problems that occur predominantly in north east of Iran. Nowadays antivenom therapy has become the most useful treatment for animal bites; however there is still a controversy about route and time of antivenom administration in spider bite. The aim of the present study was to determine the efficacy of specific antivenom in neutralizing hepatic and renal symptoms 24 h after Latrodectus dahli envenomation...
June 2016: Journal of Arthropod-borne Diseases
Ingrid de Carvalho Guimarães, Claudia Andrea Lima Cardoso, Sandro Marcio Lima, Luis Humberto da Cunha Andrade, William Fernnando Antonialli Junior
Studies related to communication on spiders show that, as in other invertebrates, the interactions between conspecifics are also made through chemical signals. Therefore, in order to assess whether the composition of cuticular compounds might be involved in interactions that occur during the days after the emergence of juveniles in Latrodectus geometricus, we conducted behavioral and cuticular chemical profiles analysis of females and juveniles of different ages. The results show that females, regardless of their reproductive state, tolerate juveniles of other females with up to 40 days post-emergence and attack juveniles of 80 days post-emergence...
May 2016: Behavioural Processes
Nicholas DiRienzo, Pierre-Olivier Montiglio
1. Developmental experience, for example food abundance during juvenile stages, is known to affect life history and behaviour. However, the life history and behavioural consequences of developmental experience have rarely been studied in concert. As a result, it is still unclear whether developmental experience affects behaviour through changes in life history, or independently of it. 2. The effect of developmental experience on life history and behaviour may also be masked or affected by individual condition during adulthood...
July 2016: Journal of Animal Ecology
Jan A Veenstra
Four genomes and two transcriptomes from six Chelicerate species were analyzed for the presence of neuropeptide and neurohormone precursors and their GPCRs. The genome from the spider Stegodyphus mimosarum yielded 87 neuropeptide precursors and 120 neuropeptide GPCRs. Many neuropeptide transcripts were also found in the transcriptomes of three other spiders, Latrodectus hesperus, Parasteatoda tepidariorum and Acanthoscurria geniculata. For the scorpion Mesobuthus martensii the numbers are 79 and 93 respectively...
April 1, 2016: General and Comparative Endocrinology
Daniel Schaal, Joschka Bauer, Kristian Schweimer, Thomas Scheibel, Paul Rösch, Stephan Schwarzinger
Spider dragline fibers are predominantly made out of the major ampullate spidroins (MaSp) 1 and 2. The assembly of dissolved spidroin into a stable fiber is highly controlled for example by dimerization of its amino-terminal domain (NRN) upon acidification, as well as removal of sodium chloride along the spinning duct. Clustered residues D39, E76 and E81 are the most highly conserved residues of the five-helix bundle, and they are hypothesized to be key residues for switching between a monomeric and a dimeric conformation...
April 2016: Biomolecular NMR Assignments
Matthew A Collin, Thomas H Clarke, Nadia A Ayoub, Cheryl Y Hayashi
Spiders in the superfamily Araneoidea produce viscous glue from aggregate silk glands. Aggregate glue coats prey-capture threads and hampers the escape of prey from webs, thereby increasing the foraging success of spiders. cDNAs for Aggregate Spider Glue 1 (ASG1) and 2 (ASG2) have been previously described from the golden orb-weaver, Nephila clavipes, and Western black widow, Latrodectus hesperus. To further investigate aggregate glues, we assembled ASG1 and ASG2 from genomic target capture libraries constructed from three species of cob-web weavers and three species of orb-web weavers, all araneoids...
February 15, 2016: Scientific Reports
Shuai Yan, Xianchun Wang
Widow spiders have received much attention due to the frequently reported human and animal injures caused by them. Elucidation of the molecular composition and action mechanism of the venoms and toxins has vast implications in the treatment of latrodectism and in the neurobiology and pharmaceutical research. In recent years, the studies of the widow spider venoms and the venom toxins, particularly the α-latrotoxin, have achieved many new advances; however, the mechanism of action of the venom toxins has not been completely clear...
December 2015: Toxins
Charles C Y Xu, Ivy J Yen, Dean Bowman, Cameron R Turner
Noninvasive genetic sampling enables biomonitoring without the need to directly observe or disturb target organisms. This paper describes a novel and promising source of noninvasive spider and insect DNA from spider webs. Using black widow spiders (Latrodectus spp.) fed with house crickets (Acheta domesticus), we successfully extracted, amplified, and sequenced mitochondrial DNA from spider web samples that identified both spider and prey to species. Detectability of spider DNA did not differ between assays with amplicon sizes from 135 to 497 base pairs...
2015: PloS One
Richard S Vetter, Jacob Tarango, Kathleen A Campbell, Christine Tham, Cheryl Y Hayashi, Dong-Hwan Choe
Information on pesticide effects on spiders is less common than for insects; similar information for spider egg sacs is scarcer in the open literature. Spider egg sacs are typically covered with a protective silk layer. When pesticides are directly applied to egg sacs, the silk might prevent active ingredients from reaching the eggs, blocking their insecticidal effect. We investigated the impact of six water-based pesticide sprays and four oil-based aerosol products against egg sacs of brown widow spiders, Latrodectus geometricus C...
February 2016: Journal of Economic Entomology
Jérôme Marie, Richard S Vetter
This paper presents two newly established species for French Polynesia: the invasive brown widow spider, Latrodectus geometricus C. L. Koch, and its potential biocontrol agent, the parasitoid wasp, Philolema latrodecti (Fullaway). The brown widow spider was recorded from the island of Moorea in 2006 and, since that discovery, the occurrence of this species has expanded to two of the five archipelagos of French Polynesia including the main island of Tahiti and four of the Cook Islands. Although the tropical climate contributes to the establishment of L...
November 2015: Journal of Medical Entomology
Dharamdeep Jain, Ci Zhang, Lydia Rose Cool, Todd A Blackledge, Chrys Wesdemiotis, Toshikazu Miyoshi, Ali Dhinojwala
Capture silks are an interesting class of biological glues that help spiders subdue their prey. Viscid capture silk produced by the orb web spiders is a combination of hygroscopic salts that aid in water uptake and interact with adhesive glycoproteins to make them soft and sticky. The orb was a stepping stone to the evolution of new web types, but little is known about the adhesives in these webs. For instance, cobweb spiders evolved from orb-weaving ancestors and utilize glue in specialized sticky gumfoot threads rather than an elastic spiral...
October 12, 2015: Biomacromolecules
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