Cone Snails The cone snails (family Conoidea) are venomous marine gastropods usually found in tropical marine waters. There are more than 500 species of cone snails and they use their venom to capture prey and to defend themselves against predators. The cone snails are grouped according to their prey preference: worms, usually polychaetes; fish; and other gastropod mollusks (Olivera, 2002). The venom is composed of biologically active peptides, which are produced in the venom duct of the snail venom apparatus (Figure 1, Olivera 2002) and are pumped by the venom bulb through the proboscis. Figure 1. Conus venom apparatus: the venom bulb, venom duct, and the radular sac with the harpoons (radular teeth). (Olivera 2002) Conus Venom and Conotoxins Conus venoms contain biologically active components, called conotoxins (conopeptides) that target different molecular receptors. They are generally 10 to 35 amino acids long. They are stabilized by disulfide-linkages, usually through cysteine residues. Post-translational modifications to the amino acids are common, such as C-terminal amidation, 4-hydroxyproline and gamma-carboxylic glutamic acid. The mature peptide toxins in the venom are processed in the endoplasmic reticulum (ER) and in the Golgi apparatus. Conopeptides are expressed as precursor proteins and are organized as such in Figure 2. The ER signal is highly conserved and is used to define the gene superfamilies of the conopeptides (Kaas et al. 2010, 2012). Figure 2. An example of a conopeptide protein precursor, Ms20.1 precursor, indicating its signal sequence (pre region), its pro region, and the mature peptide region. Based on the characteristics of the conopeptides and their biological activity, they are classified... ... middle of paper ... ...Lluisma, A. (2012). Adaptive radiation of venomous marine snail lineages and the accelerated evolution of venom peptide genes. Annals of the New York Academy of Sciences, 1267(1), 61-70. Olivera, B., Imperial, J., & Concepcion, G. (2013). Snail Peptides. Handbook of biologically active peptides (2nd ed., pp. 437-450). San Diego: Elsevier. Peracchia, C. (1994). Handbook of membrane channels: Molecular and cellular physiology. San Diego, CA: Academic Press. Schmidtko, A., Lötsch, J., Freynhagen, R., & Geisslinger, G. (2010). Ziconotide for treatment of severe chronic pain. The Lancet, 375(9725), 1569-1577. Via, M.C. (2008). [Executive Summary of the book Neurodegenerative Diseases: Next-Generation Drugs for Four Major Disorders]. Insight Pharma Reports.
Cone snails are some of the most toxic animals in the world. Cone snails have a small range in the reefs of the Indo-Pacific area. Anyone who gets stung by one of these snails likely has only a few minutes to live. However, cone snail venoms are made up of conotoxins, biologically active peptides that target neurons and muscles. Snail venom used to paralyze the prey so because of their compounds with medicinal properties cone snail can help to dismiss the cancer and produce approximately hundreds of more powerful morphine.
A. Chronic pain signifies a developing public health issue of huge magnitudes, mainly in view of aging populations in developed countries (Russo).
In some cases the eggs will get flushed out of the host. When this happens it releases miracidia that penetrate in to the snail. The snail is the intermediate host. When in the snail the organism uses asexual reproduction then development of cercariae. The cercariae can survive in...
Neurodegeneration is used mainly for diseases that are characterised by progressive loss of structure and function of neurons. There are many neurodegenerative diseases including amyotrophic lateral sclerosis that...
" Chronic Pain (CP) statistics astounding according to The Institute of medicine approximately 100 million adults suffer from chronic pain which is more than heart disease, diabetes, and cancer combined."(IOM Relieving Pain in America 2011, p. 1)
Alzheimer’s disease is the most common cause of dementia. The very first stages of Alzheimer’ include symptoms like confusion and using the right words while talking. As it gets on to later stages symptoms like loss of memory and mood swings start to appear (Begley et al., 2001). Any sort of stem cell treatment is not available to Alzheimer’s patients yet, as researchers are still conducting new experiments. There are multiple neurons that get damaged by Alzheimer’s, which makes the problem even more complex and a different approach needs to be followed every time a clinical trial is conducted.
Although Alzheimer’s disease appears to be the most common cause of dementia, “more than 50 conditions are associated with dementia, including degenerative ...
applied to prevent the circulation of the venom" (Fernandez, 2010). Fortunately, they have a very
Alzheimer’s disease is a complex illness that affects the brain tissue directly and undergoes gradual memory and behavioral changes which makes it difficult to diagnose. It is known to be the most common form of dementia and is irreversible. Over four million older Americans have Alzheimer’s, and that number is expected to triple in the next twenty years as more people live into their eighties and nineties. (Johnson, 1989). There is still no cure for Alzheimer’s but throughout the past few years a lot of progress has been made.
Fasciola Hepatica is parasite that is classified as a trematode. The life cycle of Fasciola hepatica, like Diphyllobothrium Latum, is quiet complex. Once again, unembryonated eggs start by being passed on by a definitive host such as a human, cow, sheep, or goat. The egg is durable and waits to be in an aquatic environment. Once in the aquatic environment, a miracidium hatches from the egg. The miracidium is the first ciliated larval stage of this parasite. The purpose of the miracidium is to seek out and penetrate a fresh water snail. Once the miracidium penetrate the skin of the snail, they migrate into the muscle. In the muscle, miracidium transform into sporocysts which then reproduce asexually. The sporocysts mature into redia and then into cercariae. The maturation process of the parasite in the snails typically takes five to seven weeks.CDC The tailed cercariae are then released from the snail and seek out aquatic vegetation. Once the cercariae find aquatic vegetation it encysts, or form a cyst, in the plant tissue and matures into a metacercariae. During this, the cercariae loses its tail to become non-motile and forms a very hard thick wall in the plant tissue in order to survive. This is the only larval form of the parasite that is infective to humans as well as other definitive hosts. Humans then become infected when they eat the aquatic vegetation such as watercress with the encysted metacercariae on it. When this happens the encysted parasite travels to the duodenum outside of the stomach in the small intestines and excysts, or breaks out of its cyst. The metacercariae then borrow through the lining of the small intestine into the peritoneal cavity and migrate to the liver, more specifically to the bile ducts of the liver. Once in the bile ducts the metacercariae mature into adult
n.d. - n.d. Peptides and Proteins. Proteins. Retrieved July 25, 2008, from http://www.cd http://www.cem.msu.edu/reusch/VirtualText/protein2.htm Ophardt, C. E. (2003).
“Just about every order of animal has venomous members,” says Bryan Grieg Fry, a venom researcher at the University of Queensland in Australia. “There are hundreds of thousands of [venomous] species out there.” If you look up any species of animal you will find at least one member has some kind of toxin that they use. “Although the words “venomous” and “poisonous” are used interchangeably in everyday speech, they are actually fundamentally different. By definition, venom has to be injected into the body, introduced by a bite or a sting. Poison, on the other hand, is ingested or inhaled into the body by the victim. Thus, venomous and poisonous animals are altogether different.” (Papio 2) Anim...
Figure 1. A multiple alignment comparison of orthologues prolactin from a human, zebrafish, and mouse generated using CLUSTAL W (1.83) multiple sequence alignment (Larkin MA et. al 2007). The asterisk denotes identical residue, colons denote similar amino acids, and periods denote slightly similar amino acid residues in all three sequences. The blue box represents a domain predicted to be responsible to the prolactin binding and signaling site on the protein in humans (Cooke et al. 1981). A similar “prolactin-like” region is denoted by a red box on the mouse prolactin sequence (Hagaya et. al 1986). The yellow highlight denotes signal peptides, located before the amino acids in the “prolactin-like” regions of the human and mouse, which are used to specify
Mollusks happen in practically every territory found on Earth, where they are frequently the most obvious creatures. While most are found in the marine condition, reaching out from the intertidal to the most profound seas, a few noteworthy gastropod clades live transcendently in freshwater or earthbound living spaces.
My family and I used to go to the beach every summer; on one of those trips, I encountered a small conch shell, so small that it could be held on my ring and pinky finger together. Despite its size, it looks like a fully developed one. From a centric point, the chocolate spiral shell is developed. As the shell moves away from the center, white bone lines separate the brownish layers. Going farther, three rows of spikes come out as chain...