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Biology subjects

McMullen, M.

Publications and source records attributed to McMullen, M..

2 recordsLinked to original sources

Integrated multi-omics reveals adaptive anti-oxidant remodeling in early alcohol-associated liver disease

Alcohol-associated liver disease (ALD) is a leading cause of liver-related morbidity and mortality. Although various omics approaches have revealed early metabolic alterations, individual datasets provide limited mechanistic insight. Here, we integrated RNA sequencing with mass spectrometry-based analyses to quantify gene expression, protein abundance, proteome and acetylome dynamics, and metabolic fluxes in livers of alcohol-fed mice. This multi-layered approach revealed extensive metabolic rewiring characterized by suppressed mitochondrial energy metabolism and compensatory upregulation of glutathione (GSH) production, utilization, and recycling, establishing a high-flux antioxidant network. These changes were coupled to epigenetic histone H3 remodeling, marked by increased permissive acetylation and decreased suppressive methylation, linking alcohol-induced metabolic and redox alterations to chromatin reprogramming. ChEA-based in silico upstream transcription factor analysis, identified hepatocyte nuclear factor 4 (HNF4) and nuclear factor erythroid 2-related factor 2 (NRF2) as key regulatory nodes. Alcohol exposure was associated with a modest HNF4 suppression alongside increased expression of NRF2, indicating a shift from HNF4-driven metabolic programs toward NRF2-mediated antioxidant responses. Despite acetylation-associated impairment of mitochondrial proteins, GSH-related enzymes were preserved, supporting a protective, high-turnover antioxidant response that limits early oxidative stress and defines an adaptive state maintaining redox homeostasis while potentially predisposing to ALD progression.

biochemistry↗

The complex sequence landscape of maize revealed by single molecule technologies

Complete and accurate reference genomes and annotations provide fundamental tools for characterization of genetic and functional variation. These resources facilitate elucidation of biological processes and support translation of research findings into improved and sustainable agricultural technologies. Many reference genomes for crop plants have been generated over the past decade, but these genomes are often fragmented and missing complex repeat regions. Here, we report the assembly and annotation of maize, a genetic and agricultural model species, using Single Molecule Real-Time (SMRT) sequencing and high-resolution optical mapping. Relative to the previous reference genome, our assembly features a 52-fold increase in contig length and significant improvements in the assembly of intergenic spaces and centromeres. Characterization of the repetitive portion of the genome revealed over 130,000 intact transposable elements (TEs), allowing us to identify TE lineage expansions unique to maize. Gene annotations were updated using 111,000 full-length transcripts obtained by SMRT sequencing. In addition, comparative optical mapping of two other inbreds revealed a prevalence of deletions in the low gene density region and maize lineage-specific genes.

genomics↗