title: De novo sequencing of novel neuropeptides directly from Ascaris suum tissue using matrix-assisted laser desorption/ionization time-of-flight/time-of-flight.
abstract: Direct analysis of tissue by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) allows for the rapid profiling of biological molecules with minimal loss of sample or degradation and reduced likelihood of chemical modification. However, there are still considerable challenges to overcome due to the complexity of tissue and the low quantity of endogenous peptide in a single cell. These problems are exacerbated in the nematode Ascaris suum because of the small size of individual neurons and the paucity of peptide per cell. In an effort to address these difficulties, the recently developed matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) technology was used in combination with an on-target derivatization in order to sequence novel neuropeptides directly from Ascaris nervous tissue. Direct MALDI-TOF/TOF analysis of Ascaris tissue provided the complete amino acid sequences for a previously characterized neuropeptide as well as for three novel peptides with homologues found in other nematodes. These results demonstrate a method for the rapid characterization of sub-femtomolar amounts of peptide directly from tissue using MALDI-TOF/TOF.
authors.affiliation: Neuroscience Training Program and Department of Zoology, 1117 West Johnson St., Madison, WI 53706, USA. yew@neurology.wisc.edu
authors.forename: Joanne Y
authors.initials: JY
authors.lastname: Yew
authors.forename: Sergei
authors.initials: S
authors.lastname: Dikler
authors.forename: Antony O
authors.initials: AO
authors.lastname: Stretton
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017165:Ascaris suum / Q000737:chemistry* / Q000378:metabolism; D002490:Central Nervous System / Q000737:chemistry / Q000378:metabolism; D008832:Microchemistry / Q000379:methods*; D008969:Molecular Sequence Data; D009474:Neurons / Q000737:chemistry* / Q000378:metabolism*; D009479:Neuropeptides / Q000032:analysis / Q000737:chemistry* / Q000145:classification / Q000378:metabolism*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D020539:Sequence Analysis, Protein / Q000379:methods*; D017385:Sequence Homology
chemical_list: D009479:Neuropeptides