RNA molecular recording with an engineered RNA deaminase.

RNA deaminases are powerful tools for base editing and RNA molecular recording. However, the enzymes used in currently available RNA molecular recorders such as TRIBE, DART or STAMP have limitations due to RNA structure and sequence dependence. We designed a platform for directed evolution of RNA molecular recorders.

When and where to exercise: An assessment of personal exposure to urban tropical ambient airborne pollutants in Singapore.

Background: Physical activity is associated with health benefits and has been shown to reduce mortality risk. However, exposure to high levels of ambient fine particulate matter (PM) during exercise can potentially reduce the health benefits of physical activity. This study aims to assess and compare the PM concentrations of different exercise venues in Singapore by their location attributes and time of day.

DDX3 depletion represses translation of mRNAs with complex 5' UTRs.

DDX3 is an RNA chaperone of the DEAD-box family that regulates translation. Ded1, the yeast ortholog of DDX3, is a global regulator of translation, whereas DDX3 is thought to preferentially affect a subset of mRNAs. However, the set of mRNAs that are regulated by DDX3 are unknown, along with the relationship between DDX3 binding and activity.

Copper regulates rest-activity cycles through the locus coeruleus-norepinephrine system.

The unusually high demand for metals in the brain, along with insufficient understanding of how their dysregulation contributes to neurological diseases, motivates the study of how inorganic chemistry influences neural circuitry. We now report that the transition metal copper is essential for regulating rest-activity cycles and arousal. Copper imaging and gene expression analysis in zebrafish identifies the locus coeruleus-norepinephrine (LC-NE) system, a vertebrate-specific neuromodulatory circuit critical for regulating sleep, arousal, attention, memory and emotion, as a copper-enriched unit with high levels of copper transporters CTR1 and ATP7A and the copper enzyme dopamine β-hydroxylase (DBH) that produces NE.

Multimodal LA-ICP-MS and nanoSIMS imaging enables copper mapping within photoreceptor megamitochondria in a zebrafish model of Menkes disease.

Copper is essential for eukaryotic life, and animals must acquire this nutrient through the diet and distribute it to cells and organelles for proper function of biological targets. Indeed, mutations in the central copper exporter ATP7A contribute to a spectrum of diseases, including Menkes disease, with symptoms ranging from neurodegeneration to lax connective tissue. As such, a better understanding of the fundamental impacts of ATP7A mutations on in vivo copper distributions is of relevance to those affected by these diseases.