Dataset Information

A Proximity Labeling Strategy Enables Spatial Proteomic Analysis of Inter-organelle Membrane Contacts in Living Cells

ABSTRACT: Inter-organelle membrane contacts especially mitochondria-endoplasmic reticulum contacts (MERC) conduct important biological functions including exchange of lipids and ions, and modulation of membrane dynamics. Alterations of inter-organelle membrane contacts have been implicated with the pathogenesis of diseases, such as neurodegenerative diseases, cancers and type 2 diabetes. However, the protein compositions of inter-organelle contacts remain largely unknown as no biomarker has been discovered and it’s difficult to purify intact inter-organelle contact proteins. Here, we applied a systematic approach to probe the spatial proteome of MERC in living cells by combining the bimolecular fluorescence complementation assay and a proximity labeling strategy based on APEX2. As a result, we discovered 403 highly confident MERC proteins including many well-known MERC proteins and a variety of novel protein species as well. We further validated that WFS1, BAG2, SPTLC1 and GLUD1 are enriched at MERC with high resolution fluorescent imaging. Our study provides a powerful tool to characterize the spatial proteomes of inter-organelle membrane contacts in living cells.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Maoge Zhou

LAB HEAD: Tao Xu

PROVIDER: PXD035801 | Pride | 2023-10-24

REPOSITORIES: Pride

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A proximity labeling strategy enables proteomic analysis of inter-organelle membrane contacts.

Zhou Maoge M Kong Bingjie B Zhang Xiang X Xiao Ke K Lu Jing J Li Weixing W Li Min M Li Zonghong Z Ji Wei W Hou Junjie J Xu Tao T

iScience 20230617 7

Inter-organelle membrane contacts are highly dynamic and act as central hubs for many biological processes, but the protein compositions remain largely unknown due to the lack of efficient tools. Here, we developed BiFCPL to analyze the contact proteome in living cells by a bimolecular fluorescence complementation (BiFC)-based proximity labeling (PL) strategy. BiFCPL was applied to study mitochondria-endoplasmic reticulum contacts (MERCs) and mitochondria-lipid droplet (LD) contacts. We identifi ...[more]

PMID: 37485370

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			Action	DRS
	1MERC-Ctrl.raw	Raw
	1MERC.raw	Raw
	1U2OS-CtrL.raw	Raw
	1U2OS.raw	Raw
	20210423_LFQ.msf	Msf