Cell cycle-regulated transcriptional pausing of replication-dependent histone genes.

Coordinated expression of replication-dependent (RD) histones genes occurs within the Histone Locus Body (HLB) during S phase, but the molecular steps in transcription that are cell cycle regulated are unknown. We report that RNA Pol II promotes HLB formation and is enriched in the HLB outside of S phase, including G1-arrested cells that do not transcribe RD histone genes. In contrast, the transcription elongation factor Spt6 is enriched in HLBs only during S phase.

Selection promotes age-dependent degeneration of the mitochondrial genome.

Somatic mutations in mitochondrial genomes (mtDNA) accumulate exponentially during aging. Using single cell sequencing, we characterize the spectrum of age-accumulated mtDNA mutations in mouse and human liver and identify directional forces that accelerate the accumulation of mutations beyond the rate predicted by a neutral model. "Driver" mutations that give genomes a replicative advantage rose to high cellular abundance and carried along "passenger" mutations, some of which are deleterious.

Stepwise modifications of transcriptional hubs link pioneer factor activity to a burst of transcription.

Binding of transcription factors (TFs) promotes the subsequent recruitment of coactivators and preinitiation complexes to initiate eukaryotic transcription, but this time course is usually not visualized. It is commonly assumed that recruited factors eventually co-reside in a higher-order structure, allowing distantly bound TFs to activate transcription at core promoters. We use live imaging of endogenously tagged proteins, including the pioneer TF Zelda, the coactivator dBrd4, and RNA polymerase II (RNAPII), to define a cascade of events upstream of transcriptional initiation in early Drosophila embryos.

Diverse values of nature for sustainability.

Twenty-five years since foundational publications on valuing ecosystem services for human well-being, addressing the global biodiversity crisis still implies confronting barriers to incorporating nature's diverse values into decision-making. These barriers include powerful interests supported by current norms and legal rules such as property rights, which determine whose values and which values of nature are acted on. A better understanding of how and why nature is (under)valued is more urgent than ever.

Teachers' perceptions of the barriers to assessment of mental health in schools with implications for educational policy: A systematic review.

Background: Assessment of mental health in schools has garnered increased interest in recent years. Children spend a large proportion of their waking hours in schools. Teachers can act as gatekeepers by playing a key role in identifying children with mental health difficulties in the classroom and making the necessary onward referrals to external services.