MALDI imaging mass spectrometry to investigate endogenous peptides in an animal model of Usher's disease.
Imaging MS (MSI) has emerged as a valuable tool to study the spatial distribution of biomolecules in the brain. Herein, MALDI-MSI was used to determine the distribution of endogenous peptides in a rat model of Usher's disease. This rare disease is considered as a leading cause of deaf-blindness in humans worldwide. Cryosections of brain tissue were analyzed by MALDI-MSI to differentiate between healthy and diseased rats. MSI results were highly reproducible. Tissue-specific peptides were identified by MS/MS using LC-Orbitrap and MALDI-TOF/TOF analyses. These peptides were proposed for histological classification due to their particular spatial distribution in the brain, for example, substantia nigra, corpus callosum, and hippocampus. Several endogenous peptides showed significantly increased ion densities, particularly in the colliculi superiores and in the substantia nigra of diseased rats, including peptides derived from Fsd1, dystrobrevin-β, and ProSAAS. Furthermore, several proteolytic degradation products of the myelin basic protein were identified, of which one peptide is most likely mediated by calpain-2. Our findings contribute to the characterization of this animal model and include possible peptide markers of disease.
Institute of Toxicology, Hannover Medical School, Hannover, Germany.
Bijon
B
Chatterji
Clarissa
C
Dickhut
Svenja
S
Mielke
Jonas
J
Krüger
Ingo
I
Just
Silke
S
Glage
Martin
M
Meier
Dirk
D
Wedekind
Andreas
A
Pich
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism / Q000473:pathology*; D008969:Molecular Sequence Data; D010455:Peptides / Q000032:analysis* / Q000378:metabolism; D051381:Rats; D011917:Rats, Inbred Lew; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D052245:Usher Syndromes / Q000378:metabolism / Q000473:pathology*
D010455:Peptides
Animal proteomics; Endogenous peptides; MALDI imaging; Rat brain; Usher's disease