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VAPA at the inner nuclear membrane affects nuclear lamins and nuclear morphology - RAPIDS07 experiment

ABSTRACT: Vesicle-associated membrane protein–associated protein A (VAPA) is a protein of the endoplasmic reticulum (ER) and a component of several membrane contact sites (MCSs). We now show that VAPA also localizes to the inner nuclear membrane (INM), in close proximity to nuclear lamins, INM-proteins and nucleoporins. Using our proteomics approach RAPIDS (rapamycin- and APEX-dependent identification of proteins by SILAC), we identified several nuclear proximity partners of VAPA, including emerin, different LAP2 isoforms, lamin A/C and Nup153. Depletion of VAPA in various cellular systems resulted in reduced nuclear lamin levels and aberrant nuclear morphology including the formation of membrane invaginations and tunnels. Furthermore, histone acetylation levels were altered. Our data suggest that VAPA has distinct nuclear functions, in addition to its established role as an ER-organizer.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Christof Lenz

LAB HEAD: Christof Lenz

PROVIDER: PXD065852 | Pride | 2025-12-22

REPOSITORIES: Pride

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			Action	DRS
	2021_23_I_Rodriguez_RAPIDS07_MaxQuant.zip	Other
	20250707_SDRF_2021_23_I_Rodriguez_RAPIDS07_final.tsv	Tabular
	I_Rodriguez_120421_210421_R1_L1_01.raw	Raw
	I_Rodriguez_120421_210421_R1_L1_02.raw	Raw
	I_Rodriguez_120421_210421_R1_L1_03.raw	Raw

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VAPA at the inner nuclear membrane affects nuclear lamins and nuclear morphology - RAPIDS07 experiment

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