Biology subjects

Giles, T.

Publications and source records attributed to Giles, T..

4 recordsLinked to original sources

bioRxiv2026

Coordinated immune, chloroplast and chemical defences underpin multilayered resistance to barley yellow dwarf virus and its aphid vector associated with the Hordeum bulbosum-derived Ryd4 introgression in barley

Barley yellow dwarf virus (BYDV), transmitted by the bird cherry-oat aphid (Rhopalosiphum padi L.), is among the most damaging viral diseases of barley, but the mechanisms underlying resistance to both the virus and its vector remain poorly understood. Here, we investigated resistance associated with the Hordeum bulbosum-derived Ryd4 introgression in the barley hybrid SY Kestrel by integrating behavioural, electrophysiological, physiological and multi-omics analyses with functional validation of defence metabolites. SY Kestrel exhibited constitutive volatile-mediated antixenosis together with strong post-settlement antibiosis characterised by impaired phloem feeding, reduced aphid fitness and suppression of BYDV gene expression 10 days after transmission. Integrated transcriptomic, metabolomic and small RNA analyses revealed coordinated immune activation, chloroplast remodelling and defence metabolism associated with the resistance introgression. Candidate immune regulators were identified both within the refined Ryd4 interval and the surrounding introgressed region. Maintenance of photosystem II function was accompanied by reprogramming of -linolenic acid-derived oxylipin metabolism, while phenylpropanoid and branched-chain amino acid/lysine pathways generated metabolites that directly reduced aphid survival. We demonstrate that the Ryd4 introgression coordinates constitutive vector deterrence with host defence reprogramming to restrict aphid colonisation and suppress BYDV establishment. These results provide a mechanistic framework for improving durable resistance to aphid-transmitted viruses in cereals.

systems biology↗

bioRxiv2024

Comparative transcriptome reprogramming in oak galls containing asexual or sexual generations of gall wasps

O_LIOak gall wasps have evolved strategies to manipulate the developmental pathways of their host to induce gall formation. This provides shelter and nutrients for the developing larva. Galls are entirely host tissue; however, the initiation, development, and physical appearance are controlled by the inducer. The underlying molecular mechanisms of gall formation, by which one or a small number of cells are reprogrammed and commit to a novel developmental path, are poorly understood. In this study, we sought a deeper insight into the molecular underpinnings of this process. C_LIO_LIOak gall wasps have two generations each year, one sexual, and one asexual. Galls formed by these two generations exhibit a markedly different appearance. We sequenced transcriptomes of both the asexual and sexual generations of Neuroterus quercusbaccarum and Neuroterus numismalis. We then deployed Nanopore sequencing to generate long-read sequences to test the hypothesis that gall wasps introduce DNA insertions to determine gall development. C_LIO_LIWe detected potential genome rearrangements, but did not uncover any non-host DNA insertions. Transcriptome analysis revealed that the transcriptomes of the sexual generations of distinct species of wasp are more similar than inter-generational comparisons from the same species of wasp. C_LIO_LIOur results highlight the intricate interplay between the host leaves and gall development, suggesting that season and requirements of the gall structure play a larger role than species in controlling gall development and structure. C_LI Summary StatementOak gall wasps, Neuroterus quercusbaccarum and Neuroterus numismalis, induce species-specific galls on Quercus robur leaves. We demonstrate that the sexual generation of distinct species of wasps induce more similar changes in the host than different generation galls from the same species.

plant biology↗

bioRxiv2022

Methylation genome wide profiling in lowly and highly efficient adipose somatic cell nuclear transfer in pigs

Swine is a common model organism for biomedical research. Epigenetic reprogramming in SCNT embryos does not fully recapitulate the natural DNA demethylation events at fertilisation. This study aimed to conduct a genome-wide methylation profiling to detect differentially methylated regions (DMRs) responsible for epigenetic differences in stem cells that displayed high and low efficiency of SCNT and to elucidate the low efficiency of cloning rate in pigs. Adipose tissue mesenchymal stem cells (AMSC)s lines were isolated from adipose tissue of adult male pigs (n=20; high-efficiency cells=10; low efficiency cells= 10). Reduced representation bisulfite sequencing (RRBS) was performed on an Illumina HiSeq1500. Paired-end reads were filtered to remove the adapter contamination, and low-quality reads using TrimGalore!. Filtered reads were mapped to the reference genome using Bismark. MethylKit was used to identify differentially methylated regions (DMRs) (bases and tiles), showing statistically significant differential methylation between two groups: high and low-efficiency AMSCs. Hierarchical cluster analysis according to methylation patterns clearly defined groups with low and high cloning efficiency. We report 3704 bases with statistically significant differences in methylation and 10062 tiles with statistically significant differences in methylation. Most differentially methylated sites are intergenic 62%, 31% are intronic, 4% are located in exons and 4% in promoters. 37% of differentially methylated sites are located in known CpG islands (CGIs) and 4% in CpG island shores (CGSs).

genetics↗

bioRxiv2020

Full species-wide leaf and seed ionomic diversity of Arabidopsis thaliana

O_LISoil is a heterogenous reservoir of essential elements needed for plant growth and development. Plants have evolved mechanisms to balance their nutritional needs based on availability of nutrients. This has led to genetically-based variation in the elemental composition ionome, of plants, both within and between species. C_LIO_LIWe explore this natural variation using a panel of wild-collected, geographically widespread Arabidopsis thaliana accessions from the 1001 Genomes Project including over 1,135 accessions, and the 19 parental accessions of the Multi-parent Advanced Generation Inter-Cross (MAGIC) panel, all with full-genome sequences available. C_LIO_LIWe present an experimental design pipeline for high-throughput ionomic screenings and analyses with improved normalisation procedures to account for errors and variability in conditions often encountered in large-scale, high-throughput data collection. We report quantification of the complete leaf and seed ionome of the entire collection using this pipeline and a digital tool-IonExplorer to interact with the dataset. C_LIO_LIWe describe the pattern of natural ionomic variation across the A. thaliana species and identify several accessions with extreme ionomic profiles. It forms a valuable resource for exploratory QTL, GWA studies to identify genes underlying natural variation in leaf and seed ionome and genetic adaptation of plants to soil conditions. C_LI

plant biology↗