Biology subjects

Todd, C.

Publications and source records attributed to Todd, C..

3 recordsLinked to original sources

bioRxiv2025

Short 5' UTRs serve as a marker for viral mRNA translation inhibition by the IFIT2-IFIT3 antiviral complex

Recognition of "non-self" nucleic acids, including cytoplasmic dsDNA, dsRNA, or mRNAs lacking proper 5 cap structures, is critical for the innate immune response to viruses. Here, we demonstrate that short 5 untranslated regions (UTRs), a characteristic of many viral mRNAs, can also serve as a molecular pattern for innate immune recognition via the interferon-induced proteins IFIT2 and IFIT3. The IFIT2-IFIT3 heterodimer, formed through an intricate domain swap structure resolved by cryo-EM, mediates viral mRNA 5 end recognition, translation inhibition, and ultimately antiviral activity. Critically, 5 UTR lengths <50 nucleotides are necessary and sufficient to sensitize an mRNA to translation inhibition by the IFIT2-IFIT3 complex. Accordingly, diverse viruses whose mRNAs contain short 5 UTRs, such as vesicular stomatitis virus and parainfluenza virus 3, are sensitive to IFIT2-IFIT3-mediated antiviral activity. Our work thus reveals a pattern of antiviral nucleic acid immune recognition that takes advantage of the inherent constraints on viral genome size.

microbiology↗

bioRxiv2024

Using CRISPR barcoding as a molecular clock to capture dynamic processes at single-cell resolution

Biological processes are fundamentally dynamic, yet existing methods for capturing these temporal changes are limited. We present scDynaBar, a novel approach that integrates CRISPR-Cas9 dynamic barcoding with single-cell sequencing to enable the recording of temporal cellular events. In this system, genetic barcodes accumulate mutations over a 25-day period and then are sequenced together with the transcriptome of each single cell. We propose that this gradual accumulation of genetic diversity can be exploited to create an ordered record of a cellular event. We apply this approach to track the transition from a pluripotent state to a two-cell (2C)-like state in mouse embryonic stem cells (mESCs). The results provide compelling evidence for the transient nature of the 2C-like state. Additionally, our system shows consistent mutation rates across diverse cell types in a mouse gastruloid model, underscoring its robustness and versatility across various biological contexts. This technique not only improves our ability to study single-cell dynamics but also creates new opportunities for recording other temporal signals--in other words, using dynamic barcoding as a molecular clock in individual cells. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=74 SRC="FIGDIR/small/618192v2_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@1665361org.highwire.dtl.DTLVardef@ec3114org.highwire.dtl.DTLVardef@8a3123org.highwire.dtl.DTLVardef@a0235f_HPS_FORMAT_FIGEXP M_FIG C_FIG

cell biology↗

bioRxiv2019

Curriculum-based outdoor learning for children aged 9-11: A qualitative analysis of pupils' and teachers' views.

The relationship between child health, wellbeing and education demonstrates that healthier and happier children achieve higher educational attainment. An engaging curriculum that facilitates children in achieving their academic potential has strong implications for educational outcomes, future employment prospects and health and wellbeing during adulthood. Outdoor learning is a pedagogical approach used to enrich learning, enhance school engagement and improve pupil health and wellbeing. However, its non-traditional means of achieving curricular aims are not yet recognised beyond the early years by education inspectorates. This requires evidence into its acceptability from those at the forefront of delivery. This study aimed to explore headteachers, teachers and pupils views and experiences of an outdoor learning programme within the key stage two curriculum (ages 9-11). We examine the process of implementation to offer case study evidence through 1:1 interviews with headteachers (n=3) and teachers (n=10) and focus groups with pupils aged 9-11 (n=10) from three primary schools. Interviews and focus groups were conducted at baseline and six months into implementation. Schools introduced regular outdoor learning within the curriculum. This study found a variety of perceived benefits for pupils and schools. Pupils and teachers noticed improvements in pupils engagement with learning, concentration and behaviour, as well as positive impacts on health and wellbeing and teachers job satisfaction. Curriculum demands including testing and evidencing work were barriers to implementation, in addition to safety concerns, resources and teacher confidence. Participants supported outdoor learning as a curriculum-based programme for older primary school pupils. However, embedding outdoor learning within the curriculum requires education inspectorates to place higher value on this approach in achieving curricular aims, alongside greater acknowledgment of the wider benefits to children which current measurements do not capture.

scientific communication and education↗