Proteomic mapping by rapamycin-dependent targeting of APEX2 identifies binding partners of VAPB at the inner nuclear membrane

James, Christina; Müller, Marret; Goldberg, Martin W.; Lenz, Christof; Urlaub, Henning; Kehlenbach, Ralph H.

Abstract

Vesicle-associated membrane protein–associated protein B (VAPB) is a tail-anchored protein that is present at several contact sites of the endoplasmic reticulum (ER). We now show by immunoelectron microscopy that VAPB also localizes to the inner nuclear membrane (INM). Using a modified enhanced ascorbate peroxidase 2 (APEX2) approach with rapamycin-dependent targeting of the peroxidase to a protein of interest, we searched for proteins that are in close proximity to VAPB, particularly at the INM. In combination with stable isotope labeling with amino acids in cell culture (SILAC), we confirmed many well-known interaction partners at the level of the ER with a clear distinction between specific and nonspecific hits. Furthermore, we identified emerin, TMEM43, and ELYS as potential interaction partners of VAPB at the INM and the nuclear pore complex, respectively.

Citation

James, C., Müller, M., Goldberg, M. W., Lenz, C., Urlaub, H., & Kehlenbach, R. H. (2019). Proteomic mapping by rapamycin-dependent targeting of APEX2 identifies binding partners of VAPB at the inner nuclear membrane. Journal of Biological Chemistry, 294(44), 16241-16254. https://doi.org/10.1074/jbc.ra118.007283

• Journal Article Type: Article
• Online Publication Date: Sep 13, 2019
• Publication Date: Nov 1, 2019
• Deposit Date: Sep 25, 2019
• Publicly Available Date: Sep 13, 2020
• Journal: Journal of Biological Chemistry
• Print ISSN: 0021-9258
• Electronic ISSN: 1083-351X
• Publisher: American Society for Biochemistry and Molecular Biology
• Peer Reviewed: Peer Reviewed
• Volume: 294
• Issue: 44
• Pages: 16241-16254
• DOI: https://doi.org/10.1074/jbc.ra118.007283
• Public URL: https://durham-repository.worktribe.com/output/1290566