Contryphan-Vn is a D-tryptophan-containing disulfide-constrained nonapeptide isolated from the venom of Conus ventricosus, the single Mediterranean cone snail species. The structure of the synthetic Contryphan-Vn has been determined by NMR spectroscopy. Unique among Contryphans, Contryphan-Vn displays the peculiar presence of a Lys-Trp dyad, reminiscent of that observed in several voltage-gated K(+) channel blockers. Electrophysiological experiments carried out on dorsal unpaired median neurons isolated from the cockroach (Periplaneta americana) nerve cord on rat fetal chromaffin cells indicate that Contryphan-Vn affects both voltage-gated and Ca(2+)-dependent K(+) channel activities, with composite and diversified effects in invertebrate and vertebrate systems. Voltage-gated and Ca(2+)-dependent K(+) channels represent the first functional target identified for a conopeptide of the Contryphan family. Furthermore, Contryphan-Vn is the first conopeptide known to modulate the activity of Ca(2+)-dependent K(+) channels.

Contryphan-Vn: amodulator of Ca2+-dependent K+ channels

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptides to capture their preys and for other biological purposes. Each component of Conus peptides selectively targets a specific subtype of ion channels, neurotransmitter receptors or transporters.Owing to their diversity, more than 50,000 distinct active peptides are theoretically estimated in Conus venoms. These diversified toxins are generally categorized into several superfamilies and/or families based on their characteristic arrangements of cysteine residues and pharmacological actions. Some mechanisms underlying the remarkable diversity of Conus peptides have been postulated: the distinctive gene structure,gene duplication and/or allelic selection, genus speciation, and sophisticated expression pattern and posttranslational modification of these peptides. Due to their highly pharmacological potency and target selectivity,Conus peptides have attracted extensive attention with their potentials to be developed as new research tools in neuroscience field and as novel medications in clinic for pain, epilepsy and other neuropathic disorders.Several instructive lessons for our drug development could be also learnt from these neuropharmacological "expertises". Conus peptides comprise a rich resource for neuropharmacologists, and most of them await to be explored.

Conus Peptides A Rich Pharmaceutical Treasure

Foregut anatomyc feeding mechanismsc relationships and classification of the Conoidea leToxoglossar lGastropodar

Marine world represents a large untapped reservoir for biotechnological applications as least explored diverse microorganisms and other floral and faunal diversity reside in it Marine organisms are of enormous scientific interest as they possess wide diversity, unique structures, metabolic pathways, reproductive systems, sensory and defence mechanisms due to their adaptation to the extreme environmental conditions unparalleled to their terrestrial counterparts Marine biotechnology has received huge attention nowadays due to its vast majority of applications in the field of food industry, pharmaceuticals, ornamental industry, and many more However, the knowledge in marine genomics needs to be broadened for a better output from the above-mentioned industries

Marine resources and animals in modern biotechnology

The Ambonese Curiosity Cabinet, by Georgius Everardus Rumphius (edited and translated by E.M. Beekman)

The evolutionarily unique and ecologically diverse family Conidae presents fundamental opportunities for marine pharmacology research and drug discovery.The focus of this investigation is to summarize the worldwide distribution of Conus and their species diversity with special reference to the Indian coast.In addition,this study will contribute to understanding the structural properties of conotoxin and therapeutic application of Conus venom peptides.Cone snails can inject a mix of various conotoxins and these venoms are their major weapon for prey capture,and may also have other biological purposes,and some of these conotoxins fatal to humans.Conns venoms contain a remarkable diversity of pharmacologically active small peptides;their targets are an iron channel and receptors in the neuromuscular system.Interspecific divergence is pronounced in venom peptide genes,which is generally attributed to their species specific biotic interactions.There is a notable interspecific divergence observed in venom peptide genes,which can be justified as of biotic interactions that stipulate species peculiar habitat and ecology of cone snails.There are several conopeptides used in clinical trials and one peptide(Ziconotide) has received FDA approval for treatment of pain.This perspective provides a comprehensive overview of the distribution of cone shells and focus on the molecular approach in documenting their taxonomy and diversity with special reference to geographic distribution of Indian cone snails,structure and properties of conopeptide and their pharmacological targets and future directions.

Dhanabalan

Papers

A perspective on toxicology of Conus venom peptides