Isolation of a Neuroactive Peptide from Conus mustelinus

Corn snails Corn snails (Conoidea family) are toxic marine gastropods commonly found in tropical seawater. There are over 500 cone snails that capture prey with their poisons and protect themselves from predators. Conical snails are classified according to the preference of baits, usually polychaetes, fish and other molluscanic mollusks (Olivera, 2002). Venom is produced in the venom of the snail venom device (FIG. 1, Olivera 2002) and consists of bioactive peptides pumped by poisonous spheres through the oral cavity.

In addition, more than 50 neuroactive peptides have been discovered and new peptides are regularly discovered. Many of them are "co-emitted" with small molecule emitters. However, in some cases, the peptide is the major mediator of the synapse. β-Endorphin is a relatively well-known example of peptide neurotransmitters because it interacts with opioid receptors of the central nervous system. A single ion (such as synaptic release zinc) is also considered a gas molecule such as a neurotransmitter, nitric oxide (NO), carbon monoxide (CO), hydrogen sulfide (H 2 S). Gas is produced in the neurocyte and immediately spreads through the cell membrane into the extracellular fluid and into nearby cells to stimulate the production of second messengers. Soluble gas Neurotransmitters work only for a few seconds, they decompose quickly, so research is difficult.

Neurotransmission is regulated by synaptic neurotransmitters in neural circuits. The main neurotransmitters are divided into amino acids, amines, purines, peptides and nitric oxide. In principle, neurotransmitters other than peptides are synthesized by synthase in the precursor presynaptic nerve terminal sheath, stored in synaptic vesicles, released into the synaptic cleft by exocytosis, and the postsynaptic membrane receptors are acute Of a series of signal transductions that produce short-term or long-term physiological effects. Termination of neurotransmission is accomplished by reuptake to the presynaptic nerve terminal by the plasma membrane transporter and storage of the vesicle transporter in synaptic vesicles or by degradation of metabolic enzymes (acetylcholine and peptides). Overexpression of human tyrosine hydroxylase (TH)