Search

The RNA methyltransferase activity of SPOUT1/CENP-32 is crucial for accurate mitotic spindle organization. Here, the authors describe a neurodevelopmental disorder caused by bi-allelic pathogenic SPOUT1 variants with reduced activity and compromised function in spindle organization.

Loss of an snoRNA causes the neurodevelopmental disease Prader-Willi Syndrome (PWS). Here the authors generate snoRNA-deleted pre-neuronal cell lines. Small numbers of RNAs and proteins were altered, with functions potentially linked to PWS symptoms.

Mutations in the non-coding RNA RMRP cause primary immunodeficiency. Robertson et al show that a disease-associated mutation in RMRP impairs pre-ribosomal RNA processing and reduces ribosome abundance, establishing this disorder as a ribosomopathy.

During nuclear surveillance in yeast and human cells, the RNA exosome functions together with the TRAMP complexes. Here, the authors defined the protein composition of the TRAMP complexes and identified specific RNA binding sites for the different TRAMP components.

Rea1 is an ATPase related to dynein motor proteins that has been implicated in the biogenesis of the 60S ribosomal subunit. A new cryo-EM study vividly demonstrates the power of structural methods, deciphering the role of Rea1 in monitoring key pre-60S maturation steps before the acquisition of export competence in budding yeast.

The exosome complex has key roles in RNA processing and quality control. Single-particle EM analyses now provide compelling evidence for two distinct pathways by which substrate RNAs can pass through the exosome structure to reach the catalytic site for exonuclease digestion.

The exosome complex of 3′→5′ exoribonucleases degrades many types of RNA in the nucleus and the cytoplasm that are targeted by the cell's RNA-surveillance machinery. It is also responsible for the precise trimming of the 3′ ends of nuclear RNA precursors during RNA maturation.

Ribosome-associated quality control (RQC) pathways monitor and respond to stalling of the translating ribosome. Here the authors show that the ribosome associated RQC factor Hel2/ZNF598, an E3 ubiquitin ligase, generally interacts with mRNAs in the vicinity of stop codons.

Ribosome biogenesis is influenced by the rate of RNAPI progression. Yet, mechanisms that control RNAPI elongation have remained elusive. Here, the authors show that the conserved protein Seb1 promotes cotranscriptional rRNA processing by controlling RNAPI progression.

A newly identified step in maturation of the small ribosomal particle regulated by the kinase Hrr25 is critical, for without Hrr25, immature 40S subunits accumulate.

During the final stages of yeast ribosome synthesis, immature translation-incompetent pre-40S particles that contain 20S pre-rRNA are converted to the mature translation-competent subunits containing 18S rRNA. In vitro and in vivo data now demonstrate that processing of 20S pre-rRNA is stimulated by translation initiation factor Fun12, and that its interaction with 60S ribosomal subunits is required for efficient 20S pre-rRNA processing.

Tsr1 is an essential ribosome biogenesis factor that has known similarity to GTPases. Here, the authors report the Tsr1 crystal structure and show that it is similar to GTPases but that active site residues are not conserved; modelling of the structure into the pre-40S maps allows inferences on ribosomal maturation to be drawn.

Eukaryotic ribosome biogenesis involves a large number of maturations factors which are responsible for the stepwise assembly of the ribosomal subunits. Here the authors use an array of biochemical and structural biology methods to investigate the function of the UtpA and UtpB complexes as part of the small subunit processome.

In any manufacturing process, quality control is crucial, and gene expression is no exception. A new pathway monitors mRNAs — the intermediaries of gene expression — and destroys faulty molecules.

Many different RNA species undergo nucleotide modifications at sites identified by guide small nucleolar ribonucleoprotein (snoRNP) particles. The co-crystal structure of two snoRNP proteins gives valuable clues into the workings of this system.

The information encoded in our genes must be copied into messenger RNAs, which will programme the protein-synthesis machinery. New results support an intriguing mechanism for ending the copying process.

TDP-43 controls an exon splicing event in UNC13A that results in the inclusion of a cryptic exon associated with frontotemporal dementia and amyotrophic lateral sclerosis.

Preribosomal particles need to be exported from the nucleus, but their architecture and composition have been unknown. Cryo-EM analysis of pre-60S particles bound to the nuclear export factor Arx1 provides the first structural glance at the immature 60S particle, and the position of Arx1 near the exit tunnel suggests that it may restrict access of factors active during translation.

The three-dimensional structure of pericentromeres in budding yeast is defined by convergent genes, which mark pericentromere borders and trap cohesin complexes loaded at centromeres, generating an architecture that allows correct chromosome segregation.

Two proteins are identified in yeast that regulate the timing of pre-ribosome export from the nucleus; Nug2 binds pre-60S particles until they are ready for export, at which time Nug2 is replaced by the export adaptor Nmd3, enabling the export machinery to recognise the pre-ribosome that is ready to be transferred to the cytoplasm.

Mutations associated with Treacher Collins syndrome perturb the subnuclear localization of an RNA helicase involved in ribosome biogenesis through activation of p53 protein, illustrating how disruption in general regulators that compromise nucleolar homeostasis can result in tissue-selective malformations.

Biases in synonymous codon usage are pervasive across taxa, genomes and genes, and understanding their causes has implications for molecular evolution and biotechnology. This article assesses the competing models for codon bias, in light of genome-scale and high-throughput data.

Our knowledge of the diverse types and roles of long non-coding RNAs (lncRNAs) is rapidly increasing. This Review discusses our latest understanding of lncRNAs that have validated functional roles in various differentiation and developmental processes.