Dataset Information

Determining composition of micron-scale protein deposits in neurodegenerative disease by spatially targeted optical microproteomics

ABSTRACT: Spatially targeted optical microproteomics (STOMP) is a novel proteomics technique for interrogating micron-scale regions of interest (ROI) in mammalian tissue, with no requirement for genetic manipulation. Methanol or formalin fixed specimens are stained with fluorescent dyes or antibodies to visualize ROIs, then soaked in solutions containing the photo-tag: 4-benzoylbenzyl-glycyl-hexahistidine. Confocal imaging along with two photon excitation are used to covalently couple photo-tags to all proteins within each ROI, to a resolution of 0.67 µm in the xy-plane and 1.48 µm axially. After tissue solubilization, photo-tagged proteins are isolated and identified by mass spectrometry. As a test case, we examined amyloid plaques in an Alzheimer’s disease (AD) mouse model and a postmortem AD case, confirming known plaque constituents and discovering new ones. STOMP can be applied to various biological samples including cell lines, primary cell cultures, ex vivo specimens, biopsy samples and fixed postmortem tissue.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Homo Sapiens (human) Mus Musculus (mouse)

TISSUE(S): Brain

SUBMITTER: Hongbo Guo

LAB HEAD: Avijit Chakrabartty

PROVIDER: PXD002959 | Pride | 2015-11-18

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	Contrast_NON_plaque_control_tissue.txt	Txt
	Contrast_plaques_human_Alzheimer_brain.txt	Txt
	Contrast_plaques_in_TgCRND8.txt	Txt
	DK1_140609.mzXML	Mzxml
	DK1_140609_OUT.zip	Other

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Publications

Determining composition of micron-scale protein deposits in neurodegenerative disease by spatially targeted optical microproteomics.

Hadley Kevin C KC Rakhit Rishi R Guo Hongbo H Sun Yulong Y Jonkman James E N JE McLaurin Joanne J Hazrati Lili-Naz LN Emili Andrew A Chakrabartty Avijit A

eLife 20150929

Spatially targeted optical microproteomics (STOMP) is a novel proteomics technique for interrogating micron-scale regions of interest (ROIs) in mammalian tissue, with no requirement for genetic manipulation. Methanol or formalin-fixed specimens are stained with fluorescent dyes or antibodies to visualize ROIs, then soaked in solutions containing the photo-tag: 4-benzoylbenzyl-glycyl-hexahistidine. Confocal imaging along with two photon excitation are used to covalently couple photo-tags to all p ...[more]

PMID: 26418743

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