Morphological Analysis Reveals a Compartmentalized Duct in the Venom Apparatus of the Wasp Spider ().

Spiders are one of the most successful groups of venomous animals, but surprisingly few species have been examined in sufficient detail to determine the structure of their venom systems. To learn more about the venom system of the family Araneidae (orb-weavers), we selected the wasp spider () and examined the general structure and morphology of the venom apparatus by light microscopy. This revealed morphological features broadly similar to those reported in the small number of other spiders subject to similar investigations.

An Economic Dilemma Between Molecular Weapon Systems May Explain an Arachno-atypical Venom in Wasp Spiders ().

Spiders use venom to subdue their prey, but little is known about the diversity of venoms in different spider families. Given the limited data available for orb-weaver spiders (Araneidae), we selected the wasp spider for detailed analysis. Our strategy combined a transcriptomics pipeline based on multiple assemblies with a dual proteomics workflow involving parallel mass spectrometry techniques and electrophoretic profiling.

European Medicinal Leeches-New Roles in Modern Medicine.

Before the advent of modern medicine, natural resources were widely used by indigenous populations for the prevention and treatment of diseases. The associated knowledge, collectively described as folk medicine or traditional medicine, was largely based on trial-and-error testing of plant extracts (herbal remedies) and the use of invertebrates, particularly medicinal maggots of the blowfly and blood-sucking leeches. The widespread use of traditional medicine in the West declined as scientific advances allowed reproducible testing under controlled conditions and gave rise to the modern fields of biomedical research and pharmacology.

Phylogeny-Guided Selection of Priority Groups for Venom Bioprospecting: Harvesting Toxin Sequences in Tarantulas as a Case Study.

Animal venoms are promising sources of novel drug leads, but their translational potential is hampered by the low success rate of earlier biodiscovery programs, in part reflecting the narrow selection of targets for investigation. To increase the number of lead candidates, here we discuss a phylogeny-guided approach for the rational selection of venomous taxa, using tarantulas (family Theraphosidae) as a case study. We found that previous biodiscovery programs have prioritized the three subfamilies Ornithoctoninae, Selenocosmiinae, and Theraphosinae, which provide almost all of the toxin sequences currently available in public databases.

Hirudin and Decorsins of the North American Medicinal Leech : Gene Structure Reveals Homology to Hirudins and Hirudin-like Factors of Eurasian Medicinal Leeches.

Blood-sucking leeches, some of which are referred to as medicinal leeches, have caught attention not only because of their medical purposes, but also as study organisms to conduct research within fields as diverse as neurobiology, osmoregulation, ecology, and phylogeny. Of particular interest is the question whether hemophagy in leeches is of single origin or evolved independently several times. A key component in the saliva of hematophagous leeches is hirudin, a strong natural inhibitor of thrombin and hence the blood coagulation cascade.

Hirudins and hirudin-like factors in Hirudinidae: implications for function and phylogenetic relationships.

Haematophagous leeches express a broad variety of bioactive factors that are released from the salivary gland cells into the wound of a host during feeding. Among these, hirudin is probably the best studied factor and, moreover, the only one that has successfully made the transition from nature to clinical use. Many components of the leech saliva still remain either poorly characterized or yet completely unknown.

Be ready at any time: postprandial synthesis of salivary proteins in salivary gland cells of the haematophagous leech Hirudo verbana.

Sanguivorous leeches are ectoparasites having access to body fluids of potential hosts only infrequently. During feeding, salivary proteins are released from unicellular salivary glands into the wound. These substances, among them anti-coagulants, anti-inflammatory or anti-microbial agents, allow these animals proper feeding and long-term storage of host blood in their crops for several months.

More than just one: multiplicity of Hirudins and Hirudin-like Factors in the Medicinal Leech, Hirudo medicinalis.

Blood-sucking leeches like the medicinal leech, Hirudo medicinalis, have been used for medical purposes since ancient times. During feeding, medicinal leeches transfer a broad range of bioactive substances into the host's wound to prevent premature hemostasis and blood coagulation. Hirudin is probably the best known of these substances.

May salivary gland secretory proteins from hematophagous leeches (Hirudo verbana) reach pharmacologically relevant concentrations in the vertebrate host?

Saliva of hematophagous leeches (Hirudo sp.) contains bioactive proteins which allow the leech proper feeding and storage of ingested blood, but may also exert effects in the host. Leech therapy is used to treat many different ailments in humans, although only a small fraction of salivary proteins are characterized yet.

Small bite, large impact-saliva and salivary molecules in the medicinal leech, Hirudo medicinalis.

Blood-sucking leeches have been used for medical purposes in humans for hundreds of years. Accordingly, one of the most prominent species has been named Hirudo medicinalis by Carl Linne in 1758. Feeding on vertebrate blood poses some serious problems to blood-sucking ectoparasites, as they have to penetrate the body surface of the host and to suppress the normal reactions of the host to such injuries (swelling, pain, inflammation) to remain undetected during the feeding period.