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Liu, Z.-Q.

Publications and source records attributed to Liu, Z.-Q..

3 recordsLinked to original sources

Agewise mapping of genomic oxidative DNA modification demonstrates oxidative-driven reprogramming of pro-longevity genes

The accumulation of unrepaired oxidatively damaged DNA can influence both the rate of ageing and life expectancy of an organism. Mapping oxidative DNA damage sites at whole-genome scale will help us to recognize the damage-prone sequence and genomic feature information, which is fundamental for ageing research. Here, we developed an algorithm to map the whole-genome oxidative DNA damage at single-base resolution using Single-Molecule Real-Time (SMRT) sequencing technology. We sequenced the genomic oxidative DNA damage landscape of C. elegans at different age periods to decipher the potential impact of genomic DNA oxidation on physiological ageing. We observed an age-specific pattern of oxidative modification in terms of motifs, chromosomal distribution, and genomic features. Integrating with RNA-Seq data, we demonstrated that oxidative modification in promoter regions was negatively associated with the expression of pro-longevity genes, denoting that oxidative modification in pro-longevity genes may exert epigenetic potential and thus affect lifespan determination. Together, our study opens up a new field for exploration of "oxigenetics," that focuses on the mechanisms of redox-mediated ageing. SummaryO_LIWe developed an algorithm to map the oxidative DNA damage at single-base resolution. C_LIO_LIOxidative DNA damage landscape in C. elegans illustrated an age-specific pattern in terms of motifs, chromosomal distribution, and genomic features. C_LIO_LIOxidative modification in older worms occurred higher frequency at the sex chromosome, with the preference for promoter and exon regions. C_LIO_LIOxidative modification in promoter regions of pro-longevity genes was negatively associated with their expression, suggesting the oxidative-driven transcript reprogramming of pro-longevity genes in physiological ageing. C_LI

genetics

Signal propagation via cortical hierarchies

The wiring of the brain is organized around a putative unimodal-transmodal hierarchy. Here we investigate how this intrinsic hierarchical organization of the brain shapes the transmission of information among regions. The hierarchical positioning of individual regions was quantified by applying diffusion map embedding to resting state functional MRI networks. Structural networks were reconstructed from diffusion spectrum imaging and topological shortest paths among all brain regions were computed. Sequences of nodes encountered along a path were labelled by their hierarchical position, tracing out path motifs. We find that the cortical hierarchy guides communication in the network. Specifically, nodes are more likely to forward signals to nodes closer in the hierarchy and cover a range of unimodal and transmodal regions, potentially enriching or diversifying signals en route. We also find evidence of systematic detours, particularly in attention networks, where communication is re-routed. Altogether, the present work highlights how the cortical hierarchy shapes signal exchange and imparts behaviourally-relevant communication patterns in brain networks.

neuroscience

Lysyl oxidase promotes neuronal ferroptosis exacerbating seizure-induced hippocampal damage

Epilepsy is a serious neurological disorder and characterized by recurrent and unprovoked seizures. A critical pathological factor in the seizure genesis is neuronal loss. However, mechanisms which lead to neuronal death remain elusive. Our present investigation depicted that ferroptosis, a recently discovered iron- and lipid peroxidation-dependent cell death, probably served as a mechanism in murine models of kainic acid (KA)-induced seizures. And treatment with ferroptosis inhibitors ferrostatin-1 (Fer-1), liproxstatin-1 (Lipo-1) or deferoxamine (DFO) significantly suppressed seizure severity and frequency. Using gene expression profiling in HT22 cells after glutamate exposure (a validated ferroptotic cell death model), we identified lysyl oxidase (Lox) as a novel inducer of ferroptosis. Mechanistically, Lox promoted ferroptosis via activation of extracellular regulated protein kinase (ERK)-dependent 5-lipoxygenase (Alox5) phosphorylation at serine 663 residue signaling, subsequent leading to lipid reactive oxygen species (ROS) accumulation. In a murine model of KA-induced seizure, we illustrated that administration of {beta}-aminopropionitrile (BAPN), a specific Lox inhibitor, remarkably prevented seizure generation. Overall, these findings highlight Lox, a novel identified ferroptotic regulator in neurons, serves as a potential target for seizure-related disease including epilepsy.

neuroscience