Neuropeptides structure

Matsumoto S., Fonagy A., Kurihara M., Uchiumi K., Nagamine T., Chijimatsu M. and Mitsui, T. (1992a) Isolation and primary structure of a novel pheromonotropic neuropeptide structurally related to leucopyrokinin from the armyworm larvae, Pseudaletia separata. Biochem. Biophys. Res. Commun. 182, 534-539. 

In the early 1980 s, dramatic Improvements in both peptide isolation technology and the instrumentation for structural characterization resulted in an avalanche of new insect neuropeptide structures. Of the 50-60 known structures, about half exhibit effects on the contractile activity of insect visceral muscle at physiological concentrations. This report describes the strategies and tactics that were utilized to successfully isolate, purify, and structurally characterize this group of insect neuropeptides. 

Additional myotropic/inhibitory neuropeptide structures will be characterized on the basis of immunological similarity to vertebrate and invertebrate peptide structures, and also with the techniques of molecular biology. Two initial successes with those methods are discussed in this report (17,25). In addition, antibodies raised against FMRFamide were used to isolate and structurally characterize a nonapeptide containing C-terminal FMRFamide from head extracts of Drosophila (26). Subsequently, the gene that codes for this nonapeptide and eight other FMRFamide-related structures was isolated and sequenced (27,28). 

Primary structure analyses of neuropeptides are essential for understanding the structure-function features of neuropeptides. The development of mass spectrometry (MS) tools and approaches for identifying neurological peptides has become essential for defining neuropeptide structures that correspond to... 

It is predicted that dehning neuropeptide structures by neuropeptidomics will reveal novel peptide neurotransmitters and hormones that possess biological activities. With the numerous peptidergic receptors, largely G-protein coupled receptors, with unknown functions, it is clear that increased focus on endogenous neuropeptide ligands can facilitate knowledge of peptide mechanisms for neurotransmission and endocrine communication. 

The first insect neuropeptide structurally identified in this class was adipokinetic hormone I (see Table I), isolated from the corpus cardiacum (CC) of L. migratoria... 

Neuropeptide Y (NPY) is a 36 amino acid polypqrtide with tyrosine residues at both ends of the molecule. It is characterised structurally by a PP-fold consisting of an extended polyproline helix and an a-helix connected by a (3-tum [1]. Based on structural and evolutionary criteria, NPY is closely related to peptide YY (PYY) and pancreatic polypeptide (PP). 

Cerda-Reverter JM, Larhammar D (2000) Neuropeptide Y family of peptides structure, anatomical expression, function, and molecular evolution. Biochem Cell Biol 78 371-392... 

The neuropeptide Y (NPY) belongs to a family of peptides that includes peptide YY and pancreatic polypeptide, and it is associated with several diseases such as asthma, immune system disorders, inflammatory diseases, anxiety, depression and diabetes mellitus. NPY is found in the central and peripheral nervous system, and its biological functions are mediated by interactions with five receptor sub-types, i.e. Yl, Y2, Y4, Y5 and Y6. Several studies indicate that the feeding behavior is influenced by interactions between NPY and Yl and Y5. Deswal and Roy used Cerius descriptors and genetic function approximation QSAR to investigate the structural determinants for the inhibition potency of 24 compounds with the general structure 4 for the NPY Y5 receptor [31]. The best QSAR (H = 0.720,... 

Deswal, S., Roy, N. Quantitative structure activity relationship of benzoxazinone derivatives as neuropeptide Y Y5 receptor antagonists. Eur. J. Med. Chem. 2006, 41, 552-557. 

Neuropeptide S (NPS) is a recently discovered bioactive peptide that has emerged as a new signaling molecule in the complex circuitry that modulates sleep-wakefulness and anxiety-like behavior. The peptide precursor is expressed most prominently in a novel nucleus located in the perilocus coeruleus, a brain structure with well-defined functions in arousal, stress, and anxiety. NPS was also found to induce anxiolytic-like behavior in a battery of four different tests of innate responses to stress. Infusion of NPS potently increases wakefulness and suppresses non-REM (NREM) and REM sleep (Xu et al, 2004). NPS binds to a G-protein-coupled receptor, the NPS receptor, with nanomolar affinity activation of the receptor mobilizes intracellular calcium. The NPS receptor is expressed throughout the brain, particularly in regions relevant to the modulation of sleep and waking, in the tuberomammillary region, lateral hypothalamus, and medial thalamic nuclei. 

The vast majority of neuropeptides that have been structurally characterized from nematodes are FaRPs. One other peptide, TKQELE,... 

The rapid and relatively recent determination of the structures of so many nematode neuropeptides has resulted in a huge disparity between available structural and functional data indeed, currently the physiological function of any of the known nematode neuropeptides remains unknown. Most of the accumulated data on nematode neuropeptide activities have been obtained using muscle strips of A. suum and, as a result, only provide a glimpse of the putative role for many of the peptides involved. 

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