Peptidomics 

Abstract: Abstract The naturally occurring peptides, mainly arising from the proteolytic cleavage of larger proteins, play several functions within the body (e. g. antihypertensive, immuno-modulatory, anti-microbial and antiviral, mineral carriers). Their presence or the increase of their concentration could be connected to different pathologies and thereby some peptides could be useful biomarkers for the diagnosis or prognosis of the disease. Peptidome research, particularly within biological fluids, therefore represents one of the most interesting and challenging purposes of proteomics. In this review we describe the current state-of-the-art in peptidomics-based studies of several human bodily fluids (serum, plasma, urine, cerebrospinal fluid, saliva, tears, seminal fluid, vitreous humor, pancreatic juice), emphasizing the contribution of top-down proteomic platforms to the deep structural characterization of natural peptides and their posttranslational modifications.

Abstract: Abstract Peptides of great number and diversity occur in all domains of life and exhibit a range of pharmaceutically relevant bioactivities. The complexity of biological samples including human cells or tissues, plant extracts or animal venom cocktails, often impedes the discovery of novel bioactive peptides using mass spectrometrybased peptidomics analysis. An increasing number of publicly available genome and transcriptome datasets, together with refined bioinformatics analysis, allows for rapid identification of novel peptides which may have been previously unrecognized. Moreover, a combination of information extracted from in silico mining approaches together with data derived from mass spectrometrybased studies provides new impetus for future peptidome analyses, including the discovery of novel bioactive peptides that can serve as starting points for drug development.

Abstract: Abstract Experimental techniques in omics sciences need strong support of bioinformatics tools for the data management, analysis and interpretation. Scientific community develops continuously new databases and tools. They make it possible the comparison of new experimental data with the existing ones, to gain new knowledge. Bioinformatics assists proteomics scientists for protein identification from experimental data, management of the huge data produced, investigation of molecular mechanisms of protein functions, their roles in biochemical pathways, and functional interpretation of biological processes. This article introduces the main bioinformatics resources for investigation in the protein world, with references to analyses performed by means of free tools available on the net.

Abstract: Abstract Neuropeptidomics, a mass spectrometry-based technique which aims to uncover the complete suite of neuropeptides present in a tissue, organ or cell from the brain or nervous system, has found application in studies examining physiological responses (e.g. food intake, appetite and reproduction). Neuropeptides (and peptide hormones) have long been known as regulators of mammalian physiological processes, particularly reproduction. These peptides are derived from precursor proteins and become active via proteolytic processes and post-translational modifications. A relatively large number of neuropeptides, mainly formed in the hypothalamus or the anterior pituitary of mammals, have been specifically associated with reproduction, including GnRH, NPY, PYY and kisspeptin. Here, we will present an overview of neuropeptides, their roles in reproduction and the application of neuropeptidomics in this field. We address the advantages of neuropeptidomics in reproductive studies including the high throughput identification, profiling and quantification of neuropeptides present in reproductive tissues and also discuss some of the challenges. The application of neuropeptidomics to the field of reproduction will provide the foundation for a greater understanding of how neuropeptides act to regulate reproductive function.