Dataset Information

Translation factor eIF5A controls mitochondrial protein import through the translation regulation of the mitochondrial inner membrane translocase receptor Tim50

ABSTRACT: The import of nuclear-encoded proteins into mitochondria is a key process for the right mitochondrial function. The evolutionarily conserved translation factor eIF5A is primarily known as an elongation factor which binds ribosomes to facilitate the translation of motifs with polyprolines or combinations of proline with glycine and charged amino acids. eIF5A expression is up-regulated by the transcription factor Hap1 under respiratory conditions and is essential to maintain the mitochondrial activity. Here we identify an essential polyproline-containing protein as a direct eIF5A target for translation: the mitochondrial inner membrane protein Tim50, which is the receptor subunit of the TIM23 translocase complex. We show how eIF5A directly controls the mitochondrial protein import through the alleviation of ribosome stalling along Tim50 sequence at the mitochondrial surface. Thus, the absence of eIF5A leads to the accumulation of mitochondrial protein precursors in the cytosol as well as to the induction of the mitoCPR stress response. Moreover, we show that eIF5A also affects mitochondrial functionality by reducing the translation and levels of many mitochondrial proteins. Overall, these results show for the first time how ribosome stalling negatively impacts the mitochondrial import process and explain why eIF5A is essential for the mitochondrial function.

INSTRUMENT(S): TripleTOF 6600

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: María Luz Valero

LAB HEAD: Paula Alepuz

PROVIDER: PXD043905 | Pride | 2024-10-23

REPOSITORIES: Pride

ACCESS DATA

Dataset's files

Source:

Items per page:

1 - 5 of 49

Similar Datasets

Project description:The eukaryotic translation factor eIF5A plays an essential role in translation elongation, especially across stretches of prolines and charged amino acids, and in translation termination. Although eIF5A is subjected to hypusination, a post-translational modification unique to this protein, how hypusination contributes to the eIF5A function remains elusive. Here we investigated the cellular defects induced by hypusination inhibitor GC7 (N1-guanyl-1,7-diaminoheptane). Through proteome, translatome and transcriptome analysis, we found that GC7 decreased a subset of mitochondrial proteins and DNA (mtDNA). Furthermore, chemical genomic screening using barcoded shRNA libraries identified genes for particular proteins involved in polyamine metabolism and a mitochondrial protein MPV17L2 as those altering the cytotoxicity induced by GC7. Depletion of MPV17L2 led to hypersensitivity to GC7 as well as the decreases in mitochondrial proteins and mtDNA. Moreover, metabolome analysis revealed that MPV17L2 depletion and GC7 treatment additively decreased the amount of proline and asparagine. Our results indicate that MPV17L2 displays a synthetic lethal interaction with the eIF5A hypusination targeted by GC7. The eukaryotic translation factor eIF5A plays an essential role in translation elongation, especially across stretches of prolines and charged amino acids, and in translation termination. Although eIF5A is subjected to hypusination, a post-translational modification unique to this protein, how hypusination contributes to the eIF5A function remains elusive. Here we investigated the cellular defects induced by hypusination inhibitor GC7 (N1-guanyl-1,7-diaminoheptane). Through proteome, translatome and transcriptome analysis, we found that GC7 decreased a subset of mitochondrial proteins and DNA (mtDNA). Furthermore, chemical genomic screening using barcoded shRNA libraries identified genes for particular proteins involved in polyamine metabolism and a mitochondrial protein MPV17L2 as those altering the cytotoxicity induced by GC7. Depletion of MPV17L2 led to hypersensitivity to GC7 as well as the decreases in mitochondrial proteins and mtDNA. Moreover, metabolome analysis revealed that MPV17L2 depletion and GC7 treatment additively decreased the amount of proline and asparagine. Our results indicate that MPV17L2 displays a synthetic lethal interaction with the eIF5A hypusination targeted by GC7. numerous molecules serving as valuable therapeutics. The marine natural product girolline has been described as an inhibitor of protein synthesis. Here, we demonstrate that it is not a general translation inhibitor but represents a sequence-specific modulator of translation factor eIF5A. Girolline interferes with ribosome-eIF5A interaction and induces ribosome stalling, primarily on AAA-encoded lysine. Our data furthermore indicate that eIF5A plays a physiological role in ribosome-associated quality control (RQC) and is important in maintaining the efficiency of translational progress. Girolline, therefore, provides a potent tool compound for understanding the interplay between protein production and quality control in a physiological setting and offers a new and selective means of modulating gene expression. numerous molecules serving as valuable therapeutics. The marine natural product girolline has27 been described as an inhibitor of protein synthesis. Here, we demonstrate that it is not a general28 translation inhibitor but represents a sequence-specific modulator of translation factor eIF5A.29 Girolline interferes with ribosome-eIF5A interaction and induces ribosome stalling, primarily on30 AAA-encoded lysine. Our data furthermore indicate that eIF5A plays a physiological role in31 ribosome-associated quality control (RQC) and is important in maintaining the efficiency of32 translational progress. Girolline, therefore, provides a potent tool compound for understanding33 the interplay between protein production and quality control in a physiological setting and offers34 a new and selective means of modulating gene expression.

			Action	DRS
	PA_210205_L1.wiff	Wiff
	PA_210205_L1.wiff.scan	Wiff
	PA_210205_L2.wiff	Wiff
	PA_210205_L2.wiff.scan	Wiff
	PA_210205_L3.wiff	Wiff

Dataset Information

Translation factor eIF5A controls mitochondrial protein import through the translation regulation of the mitochondrial inner membrane translocase receptor Tim50

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets