Salivary Transcriptome of the North American Medicinal Leech, Macrobdella decora

Abstract

A variety of bioactive proteins from medicinal leeches, like species of Hirudo , have been characterized and evaluated for their potential therapeutic biomedical properties. However, there has not previously been a comprehensive attempt to fully characterize the salivary transcriptome of a medicinal leech that would allow a clearer understanding of the suite of polypeptides employed by these sanguivorous annelids and provide insights regarding their evolutionary origins. An Expressed Sequence Tag (EST) library-based analysis of the salivary transcriptome of the North American medicinal leech, Macrobdella decora, reveals a complex cocktail of anticoagulants and other bioactive secreted proteins not previously known to exist in a single leech. Transcripts were identified that correspond to each of saratin, bdellin, destabilase, hirudin, decorsin, endoglucoronidase, antistatin, and eglin, as well as to other previously uncharacterized predicted serine protease inhibitors, lectoxin-like c-type lectins, ficolin, disintegrins and histidine-rich proteins. This work provides a lens into the richness of bioactive polypeptides that are associated with sanguivory. In the context of a well-characterized molecular phylogeny of leeches, the results allow for preliminary evaluation of the relative evolutionary origins and historical conservation of leech salivary components. The goal of identifying evolutionarily significant residues associated with biomedically significant phenomena implies continued insights from a broader sampling of blood-feeding leech salivary transcriptomes.

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

“…Haemadin, despite a relatively high degree of overall similarity, exhibits a different mode of action on thrombin in comparison to hirudins. In recent years, several attempts were made to generate and analyze whole transcriptome datasets of hematophagous leeches including Macrobdella decora (Min et al 2010), Hirudo verbana and Aliolimnatis fenestrata (Kvist el al. 2013a), Haemadipsa interrupta (Kvist el al.…”

Purification and characterization of two platelet-aggregation inhibitors, named angustatin and H-toxin TA2, from the venom of Dendroaspis angusticeps

“…These polypeptides shared very weak sequence homology to Crotalid and Viperidae family inhibitors, except for the RGD sequence region in the peptide, and showed high sequence homology with the short-chain postsynaptic neurotoxins (Smith et al, 1988). Decorsin from Macrobdella decora (North American medicinal leech) also exhibited high sequence homology with a-neurotoxin and hirudin, which is a thrombin inhibitor rather than a snake venom disintegrin (Min et al, 2010). The RGD sequence regions in these polypeptides also existed in the top of the hairpin loops.…”

Anticoagulant Potential of Marine Polychaete (Nereis Species)

“…Anticoagulants have been reported from leech (one of the class of phylum annelida) 26 . Leech salivary glands produce a more diverse pharmacological cocktail of a wide variety of anticoagulants 27,28 that not only assist in phlebotomy by keeping blood flowing in and around an incision wound but that also keep the blood from coagulating inside the leech crop during the long periods of digestion 29 . Homogenization of a 1 kg portion of whole Nereis sp.…”