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Translation can be initiated from a specific start codon using trans-RNA.

Under stress, such as heat shock, the N⁶-methyladenosine (m⁶A) modification is shown to accumulate primarily in the 5′ untranslated region of induced mRNAs owing to the translocation of an m⁶A interacting protein, YTHDF2, into the nucleus, resulting in increased cap-independent translation of these mRNAs, indicating one possible mechanism by which stress-responsive genes can be preferentially expressed.

CHIP — a co-chaperone/ubiquitin ligase — not only targets chaperone substrates for degradation, but mediates Hsp70 turnover after misfolded substrates have been depleted. The sequential catalysis of the CHIP-associated chaperone adaptor and its bound substrate provides a mechanism for maintaining homeostasis by tuning chaperone levels appropriately to reflect the status of protein folding within the cytoplasm.

Translation elongation entails a one-codon movement of the mRNA–tRNA complex along the mRNA and is catalyzed by the forward translocase EF-G. The structurally related back-translocase EF4 catalyzes movement in the opposite direction when the ribosome stalls, but its physiological role in mammals had been unknown. Genetic ablation of EF4 in mice is now found to cause testis-specific mitochondrial deficiency and impaired spermatogenesis.

Nutrient stress induces ATF4 expression via translation reinitiation, which involves eIF3 retainment on the elongating ribosome. This translational reprogramming is mediated by stress-induced removal of the O-GlcNAc modification from eIF3a.

Several functions have been proposed for m⁶A in RNA metabolism, yet little is known regarding the specific functions of individual m⁶A readers. Here, the authors observe that the m⁶A reader YTHDC2 — which contains an RNA helicase domain — acts on the coding region to promotes mRNA translation by resolving secondary structures.

Fusion of Cas9 with m6A writers METTL3 and METTL14 or eraser ALKBH5 enables site-specific writing or erasing of RNA m6A modifications in mammalian cells and investigation of individual m6A modification-mediated function.

O-GlcNAcylation of translation initiation factor component eIF4GI blocks interactions to poly(A)-binding protein Pab1 to induce disassembly of stress granules, releasing Hsp70-induced mRNAs and leading to translation of protective proteins

Start codon selection is commonly thought to occur through the unidirectional scanning of the mRNA by the 40 S ribosome. Here the authors provide evidence that the pre-initiation complex can backslide on the mRNA to initiate translation at upstream AUG codons.

Mao et al. reported ribosomal frameshifting events shortly after start codon selection, which is influenced by the sequence context and controlled by initiation factor eIF5B. This translational ‘noise’ is increased in response to nutrient starvation.

Glutathione peroxidase 4 (GPX4) inhibits ferroptosis, but protein synthesis is inefficient and costly. Here, the authors reveal that cystine uptake promotes GPX4 synthesis by activating mTORC1 and show that cancer cells are sensitized to ferroptosis by mTORC1 inhibition.

QTI-seq (quantitative translation initiation sequencing) maps the position of the start codon and thus allows the determination of initiation efficiency in response to various stimuli, such as starvation, in cell culture and in vivo.

Massively parallel reporter assays from a synthetic mRNA library identify sequence features of 5′ UTRs that control mRNA translatability and reveal ribosome-dependent and ribosome-independent mRNA-surveillance pathways.

The bacterial pathogen Legionella pneumophila uses effectors — toxins — to facilitate pathogenesis within host cells. A recent study identifies dual mechanisms of the effector SidI as an inhibitor of translation elongation. The N-terminal domain mimics tRNA, whereas the C-terminal domain glycosylates the ribosome.

A stress-induced cytosolic isoform of the mitochondrial ribosomal protein MRPL18 facilitates the specific translation of heat-shock proteins during the general shutdown of protein synthesis that occurs in response to cellular stress.

The ribosome decodes messenger RNAs and constructs proteins based on the genetic blueprint. Ribosomes also associate with non-coding RNAs, such as PIWI-interacting RNA (piRNA) precursors, during the meiotic pachytene stage. Intriguingly, the ribosome mediates pachytene piRNA biogenesis by guiding endonucleolytic cleavage of piRNA precursors.

A growing body of evidence suggests that cotranslational folding occurs from bacteria to mammalian cells, in particular for multi-domain proteins. In the assembly of yeast proteasomes, the initial interaction of Rpt1 and Rpt2 subunits has been found to take place on the translating ribosomes, coordinated by elongation pausing and involving the formation of Not1-containing compartments.