Quantitative Phosphoproteomic Analysis of Brain Tissues.

Area of Science:

• Neuroscience
• Biochemistry
• Proteomics

Background:

• Protein phosphorylation is crucial for brain development and neuronal function.
• Altered phosphorylation patterns are implicated in neurobiological disorders, including Alzheimer's disease.
• Phosphoproteomic analysis offers a way to map protein modifications and understand cellular activities.

Purpose of the Study:

• To develop and present a mass spectrometry (MS)-based protocol for quantitative phosphoproteomic analysis.
• To apply this protocol to human postmortem brain samples from Alzheimer's disease patients and controls.
• To enable comprehensive profiling of phosphorylation events in neurological disease research.

Main Methods:

• An isobaric labeling protocol was used for quantitative comparison of up to ten brain samples.
• Protein extraction, digestion, and labeling were performed, followed by sample pooling.
• Peptide fractionation using basic pH reversed-phase liquid chromatography (LC) and phosphopeptide enrichment (titanium dioxide method) were employed before LC-MS/MS analysis.

Main Results:

• The protocol enables the quantitative analysis of the phosphoproteome in human postmortem brain tissue.
• Tens of thousands of phosphorylation events were identified and analyzed.
• The method is adaptable for profiling phosphoproteomes in various biological samples.

Conclusions:

• The developed MS-based protocol provides a robust method for quantitative phosphoproteomics.
• This approach facilitates the study of phosphorylation changes in Alzheimer's disease and potentially other neurobiological disorders.
• The protocol's adaptability enhances its utility for broad biological research.