title: Proteomic characterization of neuromelanin granules isolated from human substantia nigra by laser-microdissection.
abstract: Neuromelanin is a complex polymer pigment found primarily in the dopaminergic neurons of human substantia nigra. Neuromelanin pigment is stored in granules including a protein matrix and lipid droplets. Neuromelanin granules are yet only partially characterised regarding their structure and function. To clarify the exact function of neuromelanin granules in humans, their enrichment and in-depth characterization from human substantia nigra is necessary. Previously published global proteome studies of neuromelanin granules in human substantia nigra required high tissue amounts. Due to the limited availability of human brain tissue we established a new method based on laser microdissection combined with mass spectrometry for the isolation and analysis of neuromelanin granules. With this method it is possible for the first time to isolate a sufficient amount of neuromelanin granules for global proteomics analysis from ten 10 μm tissue sections. In total 1,000 proteins were identified associated with neuromelanin granules. More than 68% of those proteins were also identified in previously performed studies. Our results confirm and further extend previously described findings, supporting the connection of neuromelanin granules to iron homeostasis and lysosomes or endosomes. Hence, this method is suitable for the donor specific enrichment and proteomic analysis of neuromelanin granules.
authors.affiliation: Medizinisches Proteom-Center, Ruhr-University Bochum, Bochum, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Plum
authors.affiliation: Medizinisches Proteom-Center, Ruhr-University Bochum, Bochum, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Steinbach
authors.affiliation: Institute of Neuroscience and Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Johannes
authors.initials: J
authors.lastname: Attems
authors.affiliation: Institute of Neuroscience and Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, United Kingdom.
authors.forename: Sharon
authors.initials: S
authors.lastname: Keers
authors.affiliation: University Hospital Wuerzburg, Center of Mental Health; Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy, Fuechsleinstrasse 15, D-97080 Wuerzburg, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Riederer
authors.affiliation: Center of Mental Health, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital of Würzburg, University of Würzburg, Würzburg, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Gerlach
authors.affiliation: Medizinisches Proteom-Center, Ruhr-University Bochum, Bochum, Germany.
authors.forename: Caroline
authors.initials: C
authors.lastname: May
authors.affiliation: Medizinisches Proteom-Center, Ruhr-University Bochum, Bochum, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Marcus
mesh_terms: D003594:Cytoplasmic Granules / Q000378:metabolism*; D059290:Dopaminergic Neurons / Q000166:cytology / Q000378:metabolism*; D005260:Female; D006801:Humans; D061346:Laser Capture Microdissection; D008297:Male; D008543:Melanins; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D013378:Substantia Nigra / Q000166:cytology / Q000378:metabolism*
chemical_list: D008543:Melanins; D009419:Nerve Tissue Proteins; D020543:Proteome; C014121:neuromelanin