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Yanyan Liu

Publications and source records attributed to Yanyan Liu.

3 recordsLinked to original sources

Comparative Genome-Wide Association Studies of Metabolites and Grain-Related Traits in Common Wheat.

The metabolome is highly diverse and the closest layer to phenotype; therefore, it is commonly regarded as a bridge between the genome and phenome in plants. Here, we performed large-scale metabolome analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and 33 grain-related traits in a diverse panel of natural accessions and a recombinant inbred line (RIL) population. We identified a new network of 2286 associations between 947 metabolites and 33 grain-related traits. Systematic integration of metabolic genome-wide association study (mGWAS) and metabolic quantitative trait locus (mQTL) analyses identified 33 566 significant single-nucleotide polymorphisms (SNPs) and 3128 mQTL. Thirteen annotated metabolites co-localized within a physical interval on 7A. Integration of metabolite-based and phenotype-based GWAS and QTL revealed an overlapped region for gibberellin A4 (GA4) content and grain roundness on 4A. Phenotyping of an ethyl methanesulfonate (EMS)-induced mutant confirmed the role of TaSDR in regulating GA4 content and grain morphology. These findings provide novel insights into the metabolic pathways influencing key grain-related traits and advance our understanding of the complex molecular mechanisms regulating grain metabolites and phenotypes in wheat. The identified metabolic markers and candidate genes provide valuable targets for molecular breeding programs aimed at improving wheat yield and quality.

QTL

Haplotype-resolved 3D genome maps reveal RNAPII-mediated allelic regulation in hybrid rice.

To understand how the two parental genomes coordinate transcription in hybrids, chromatin architecture must be resolved at the haplotype level. Here, using phased Bridge-Linker Hi-C, we reconstructed a haplotype-resolved three-dimensional (3D) genome of the elite hybrid rice (Oryza sativa) line Shanyou 63 (SY63). We identified extensive allele-specific chromatin conformations. Furthermore, we generated allele-resolved RNAPII ChIA-PET maps and phased transcriptomes to explore how chromatin interactions contribute to allelic regulation. Although maternal and paternal homologs share broadly similar chromatin features, we detected widespread haplotype-biased RNAPII binding and chromatin looping at high resolution. These allele-specific RNAPII-mediated contacts were significantly associated with biased expression. Stronger RNAPII binding on one haplotype promoted the formation of long-range regulatory loops with distal genes, thereby contributing to allele-biased transcription at a subset of loci, even when promoter-proximal RNAPII occupancy was comparable between alleles. These results demonstrate that subtle differences in RNAPII engagement and 3D regulatory wiring between parental haplotypes can reshape transcriptional output in hybrids, providing new insights into the mechanisms underlying the allelic regulation of gene expression.

Allele-specific chromatin interactions

High Hcy regulates fluid shear stress pathway activity through histone H3K79 homocysteinylation in hyperhomocysteinemia-related child hypertension.

BACKGROUND: The rise of hypertension in children has been increasingly associated with hyperhomocysteinemia (HHcy), which is recognized as a major risk factor. However, the underlying mechanisms linking homocysteine and hypertension (termed HHYP) are not fully understood. METHODS: This study utilized plasma samples from 27 control children and 27 children with HHYP (aged 8 ~ 16 years) for TMT6-labeled proteomic quantification, identifying significant altered proteins. Bioinformatics analysis revealed pathway alterations. Verification was carried out via parallel reaction monitoring (PRM) and western blot (WB) analyses. Additionally, a rat model of HHYP induced by high methionine diets, and umbilical vein endothelial cell models exposed to high homocysteine (hcy) levels were developed to investigate the molecular underpinnings further. Protein expression changes and epigenetic modifications were assessed using WB, immunohistochemistry (IHC), and ChIP-qPCR techniques. RESULTS: Key findings indicated that 357 proteins and 69 pathways were altered in children with HHYP. Specifically, 12 proteins within the fluid shear stress and atherosclerosis (FSSA) pathway showed differential expression, including the downregulation of TRX1 and GPX1 and the upregulation of ICAM1. The same expression patterns were noted in both the HHYP rat aortic tissues and the high hcy cultured endothelial cells. Moreover, elevated H3K79hcy modification levels were observed alongside epigenetic regulation of genes related to the FSSA pathway. Importantly, folic acid (FA), a medication frequently used in the clinical treatment of HHYP, has been demonstrated to effectively reverse H3K79hcy modifications and restore the disrupted FSSA pathway in both animal models and cell cultures. CONCLUSIONS: The present study suggests that HHcy may contribute to hypertension through the epigenetic dysregulation of the FSSA pathway mediated by H3K79hcy. Furthermore, the pediatric proteomics data gleaned from this study offer new clinical insights into the pathophysiology of HHYP in children.

Hyperhomocysteinemia