Visualization of cytosolic ribosomes on the surface of mitochondria by electron cryo‐tomography

Gold, Vicki A. M.; Chrościcki, Piotr; Brągoszewski, Piotr; Chacińska, Agnieszka

doi:10.15252/embr.201744261

Cited by 143 publications

(132 citation statements)

References 87 publications

Supporting

Mentioning

104

Contrasting

Order By: Relevance

“…These results agree with previous findings that the 3′ UTR of ATP2 mRNA from S. cerevisiae is important for efficient mitochondrial uptake of mature Atp2p . A close link between RNA biology and mitochondrial protein import is thus an emerging theme in mitochondrial biology .…”

Section: Discussionsupporting

confidence: 92%

The key protein of endosomal mRNP transport Rrm4 binds translational landmark sites of cargo mRNAs

et al. 2018

View full text Add to dashboard Cite

RNA‐binding proteins (RBPs) determine spatiotemporal gene expression by mediating active transport and local translation of cargo mRNAs. Here, we cast a transcriptome‐wide view on the transported mRNAs and cognate RBP binding sites during endosomal messenger ribonucleoprotein (mRNP) transport in Ustilago maydis. Using individual‐nucleotide resolution UV crosslinking and immunoprecipitation (iCLIP), we compare the key transport RBP Rrm4 and the newly identified endosomal mRNP component Grp1 that is crucial to coordinate hyphal growth. Both RBPs bind predominantly in the 3′ untranslated region of thousands of shared cargo mRNAs, often in close proximity. Intriguingly, Rrm4 precisely binds at stop codons, which constitute landmark sites of translation, suggesting an intimate connection of mRNA transport and translation. Towards uncovering the code of recognition, we identify UAUG as specific binding motif of Rrm4 that is bound by its third RRM domain. Altogether, we provide first insights into the positional organisation of co‐localising RBPs on individual cargo mRNAs.

show abstract

Section: Discussionsupporting

confidence: 92%

The key protein of endosomal mRNP transport Rrm4 binds translational landmark sites of cargo mRNAs

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Indeed, cytoplasmic ribosomes have long been detected in biochemical preparations of mitochondria, but were recently visualized directly at the mitochondrial surface using cryo-EM coupled to sensitive direct electron detectors. 24 These data demonstrate RNA localization precedes mitochondrial import for a significant subset of mitochondrial proteins. The conserved localization of mRNAs to mitochondria suggests this is an ancient paradigm that contributes to mitochondrial function.…”

Section: Rna Localization To Intracellular Membranes Contributes Tomentioning

confidence: 80%

“…The localization of mitochondrial RNAs to the mitochondrial outer membrane raises the question of co‐translational import. Indeed, cytoplasmic ribosomes have long been detected in biochemical preparations of mitochondria, but were recently visualized directly at the mitochondrial surface using cryo‐EM coupled to sensitive direct electron detectors . These data demonstrate RNA localization precedes mitochondrial import for a significant subset of mitochondrial proteins.…”

Section: The Contribution Of Rna Localization To Acute Cellular Respomentioning

confidence: 96%

RNA localization regulates diverse and dynamic cellular processes

Ryder

Lerit

2018

Traffic

View full text Add to dashboard Cite

At the nexus of specialized cellular responses are localized enrichments of protein activity. The localization of messenger RNA (mRNA) coupled with translational control often plays a crucial role in the generation of protein concentrations at defined subcellular domains. Although mRNA localization is classically associated with large specialized cells, such as neurons and embryos, RNA localization is a highly conserved paradigm of post-transcriptional regulation observed in diverse cellular contexts. Functions of localized mRNAs extend far beyond the well-studied examples of neuronal polarization and developmental patterning. Since the initial discovery of the intracellular localization of cytoskeletal mRNAs within migrating cells, hundreds of mRNAs are now known to be enriched at specific organelles where they contribute to cell function. In this short review, we discuss basic principles regulating RNA localization and consider the contribution of localized mRNA to several essential cellular behaviors. We consider RNA localization as a mechanism with widespread implications for cellular function.

show abstract

“…Oligomerization may improve import efficiency by clustering of Tom40 pores, particularly when protein 290 import occurs cotranslationally, during which many precursor molecules would be produced locally by 291 polysomes 47,48 . In addition, the orientation of Tom6's N-terminal segment toward the Tom40 pore may 292 suggest a 'hand-off' function that facilitates interaction of the Tom40 pore with precursor proteins, thereby 293 increasing translocation efficiency.…”

Section: Discussion 270mentioning

confidence: 99%

“…However, the underlying mechanism by which the TOM complex 47 enables these events has been unclear. In particular, how the Tom40 channel interacts with mitochondrial 48 targeting sequences is poorly understood. Interaction of such presequences (N-terminal cleavable 49 sequences that target ~60-70% mitochondrial precursor proteins) is a key step in translocation 11,[24][25][26] .…”

Section: Introduction 22mentioning

confidence: 99%

Cryo-EM structure of the mitochondrial protein-import channel TOM complex from Saccharomyces cerevisiae

Tucker¹,

Park

2019

Preprint

View full text Add to dashboard Cite

9Nearly all mitochondrial proteins are encoded by the nuclear genome and imported into mitochondria 10 following synthesis on cytosolic ribosomes. These precursor proteins are translocated into mitochondria 11 by the TOM complex, a protein-conducting channel in the mitochondrial outer membrane. Using cryo-EM, 12we have obtained high-resolution structures of both apo and presequence-bound core TOM complexes 13from Saccharomyces cerevisiae in dimeric and tetrameric forms. Dimeric TOM consists of two copies each of 14 five proteins arranged in two-fold symmetry-Tom40, a pore-forming β-barrel with an overall negatively-15 charged inner surface, and four auxiliary α-helical transmembrane proteins. The structure suggests that 16 presequences for mitochondrial targeting insert into the Tom40 channel mainly by electrostatic and polar 17interactions. The tetrameric complex is essentially a dimer of dimeric TOM, which may be capable of 18forming higher-order oligomers. Our study reveals the molecular organization of the TOM complex and 19provides new insights about the mechanism of protein translocation into mitochondria. 20 21

show abstract

Visualization of cytosolic ribosomes on the surface of mitochondria by electron cryo‐tomography

Cited by 143 publications

References 87 publications

The key protein of endosomal mRNP transport Rrm4 binds translational landmark sites of cargo mRNAs

The key protein of endosomal mRNP transport Rrm4 binds translational landmark sites of cargo mRNAs

RNA localization regulates diverse and dynamic cellular processes

Cryo-EM structure of the mitochondrial protein-import channel TOM complex from Saccharomyces cerevisiae

Contact Info

Product

Resources

About