Dataset Information

De-novo synthesized targets of NMD and ER stress

ABSTRACT: Nonsense-mediated mRNA decay (NMD) has originally been described as a surveillance mechanism to inhibit the expression of mRNAs with truncated open reading frames (ORFs) and to contribute to the fidelity of gene expression. It is now recognized that NMD also controls the expression of physiological genes with “intact” mRNA. Stress can decrease NMD efficiency and thus increase the mRNA levels of physiological NMD targets. As stress can also inhibit translation, the net outcome for shaping the proteome is difficult to predict. We have thus analyzed de-novo protein synthesis in response to NMD inhibition or the induction of mild endoplasmic reticulum (ER) stress by treatment of cells with the reducing agent dithiotreitol (DTT). We combined pulsed azidohomoalanine (AHA) and stable isotope labeling by amino acids in cell culture (SILAC). Labeled proteins were purified by click chemistry-based covalent coupling to agarose beads, trypsinized, fractionated, and analyzed by LC-MS/MS. We find that mild ER stress upregulates the de-novo synthesis of components of all three branches of the unfolded protein response (PERK, IRE1a and ATF6) without increasing eIF2a phosphorylation or impairing of protein translation. In contrast, inhibition of NMD induces de-novo protein synthesis of downstream targets of the PERK and IRE1a pathways but not the ATF6 pathway. These data thus support a model that implicates a positive feedback loop of ER stress inhibiting NMD efficiency which further promotes the ER stress response in a branch-specific manner.

INSTRUMENT(S): LTQ Orbitrap Velos

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Cell Culture

DISEASE(S): Cervix Carcinoma

SUBMITTER: Jana Sieber

LAB HEAD: Andreas E. Kulozik

PROVIDER: PXD002648 | Pride | 2016-02-22

REPOSITORIES: Pride

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			Action	DRS
	130502SL_Loeber_A1_F1.raw	Raw
	130502SL_Loeber_A1_F10.raw	Raw
	130502SL_Loeber_A1_F2.raw	Raw
	130502SL_Loeber_A1_F3.raw	Raw
	130502SL_Loeber_A1_F4.raw	Raw

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Publications

Proteomic Analysis Reveals Branch-specific Regulation of the Unfolded Protein Response by Nonsense-mediated mRNA Decay.

Sieber Jana J Hauer Christian C Bhuvanagiri Madhuri M Leicht Stefan S Krijgsveld Jeroen J Neu-Yilik Gabriele G Hentze Matthias W MW Kulozik Andreas E AE

Molecular & cellular proteomics : MCP 20160220 5

Nonsense-mediated mRNA decay (NMD) has originally been described as a surveillance mechanism to inhibit the expression of mRNAs with truncated open reading frames (ORFs) and to contribute to the fidelity of gene expression. It is now recognized that NMD also controls the expression of physiological genes with "intact" mRNA. Stress can decrease NMD efficiency and thus increase the mRNA levels of physiological NMD targets. As stress can also inhibit translation, the net outcome for shaping the pro ...[more]

PMID: 26896796

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