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Garduno, M.

Publications and source records attributed to Garduno, M..

2 recordsLinked to original sources

Chromosome-level genome assembly and annotation of the degu (Octodon degus)

High-quality reference genomes are essential for comparative and functional genomics yet remain unavailable for many emerging model organisms. Here, we report OctDeg2.0, a chromosome-level genome assembly and annotation of the degu (Octodon degus), generated using PacBio HiFi long-read sequencing and Hi-C scaffolding from a single male individual. Octodon degus is of growing interest as a natural animal model for aging and Alzheimers disease research. The 3.4 billion base-pair assembly comprises 28 autosomes and both sex chromosomes, with markedly improved contiguity and completeness over the prior short-read assembly while maintaining high base accuracy. The new assembly provides substantially enhanced gene annotation, clearer resolution of chromatin architecture and cis-regulatory element landscapes, with much improved characterization of repetitive and structurally complex regions, including centromeres and segmental duplications. We present a streamlined and reproducible pipeline for high-resolution de novo genome assembly and gene annotation applicable to other emerging model organisms. This work establishes a robust genomic resource for studying molecular and cellular mechanisms in health and disease in Octodon degus.

genomics↗

Epigenetic and 3D genome reprogramming during the aging of human hippocampus

Age-related cognitive decline is associated with altered physiology of the hippocampus. While changes in gene expression have been observed in aging brain, the regulatory mechanisms underlying these changes remain underexplored. We generated single-nucleus gene expression, chromatin accessibility, DNA methylation, and 3D genome data from 40 human hippocampal tissues spanning adult lifespan. We observed a striking loss of astrocytes, OPC, and endothelial cells during aging, including astrocytes that play a role in regulating synapses. Microglia undergo a dramatic switch from a homeostatic state to a primed inflammatory state through DNA methylome and 3D genome reprogramming. Aged cells experience erosion of their 3D genome architecture. Our study identifies age-associated changes in cell types/states and gene regulatory features that provide insight into cognitive decline during human aging.

genomics↗