Biology subjects

Furst, A.

Publications and source records attributed to Furst, A..

4 recordsLinked to original sources

bioRxiv2025

Integrated omics analysis reveals human milk oligosaccharide biosynthesis programs in human lactocytes

Human milk oligosaccharides (HMOs) are integral to infant health. Yet, their complex biosynthesis pathways in the mammary gland during lactation remain under characterized. To address this knowledge gap, we performed integrated analyses of single-cell RNA-sequencing (scRNA-seq) datasets combined with select HMO concentration measures. We identify differential expression patterns of known HMO synthesis genes in epithelial subsets and nominate several candidate genes that vary with HMO concentration. Additionally, we identify novel gene patterns and transcription factors that may regulate the expression of HMO biosynthesis genes and the cellular pathways supporting HMO production. Finally, we demonstrate that co-expression of HMO synthesis genes and milk fat synthesis genes is limited, suggesting distinct epithelial cell subtypes may be responsible for the production of different milk components. Our study suggests that HMO synthesis may be achieved through cell type specialization within the lactocyte compartment.

systems biology↗

bioRxiv2024

Srs2/PARI DNA helicase mediates abscission inhibition in response to chromatin bridges in yeast and human cells

The coordination of chromosome segregation with cytokinesis is crucial for maintaining genomic stability. Chromatin bridges, arising from DNA replication stress or catenated chromosomes, can interfere with this process, leading to genomic instability if not properly managed. Here, we uncover that the budding yeast DNA helicase Srs2 and its human homolog PARI delay the timing of abscission events in the presence of chromatin bridges. We demonstrate that Srs2 is essential for delaying abscission in yeast cells with chromatin bridges, and preventing their damage by cytokinesis. In human cells, PARI similarly plays a key role in delaying abscission events, such as midbody severing and actin patch disassembly during cytokinesis, in response to chromatin bridges caused by topoisomerase II inhibition. Our results also show that PARI functions within the Aurora B-mediated abscission checkpoint pathway. These findings reveal an evolutionarily conserved role of the Srs2/PARI DNA helicase in maintaining genomic integrity by modulating abscission timing in response to chromatin bridge formation.

cell biology↗

bioRxiv2024

Gene-specific RNA homeostasis revealed by perturbation of the NuA4/Tip60 acetyltransferase complex

Transcript buffering entails the reciprocal modulation of mRNA synthesis and degradation rates to maintain stable RNA levels under varying cellular conditions. Current research supports a global, non-sequence-specific connection between mRNA synthesis and degradation, but the underlying mechanisms are still unclear. In this study, we investigated changes in RNA metabolism following acute depletion of TIP60/KAT5, the acetyltransferase subunit of the NuA4 transcriptional coactivator complex, in mouse embryonic stem cells. By combining RNA sequencing of nuclear, cytoplasmic, and newly synthesised transcript fractions with biophysical modelling, we demonstrate that TIP60 predominantly enhances transcription of numerous genes, while a smaller set of genes undergoes TIP60-dependent transcriptional repression. Surprisingly, transcription changes caused by TIP60 depletion were offset by corresponding changes in RNA nuclear export and cytoplasmic stability, indicating gene-specific buffering mechanisms. Similarly, disruption of the unrelated ATAC coactivator complex also resulted in gene-specific transcript buffering. These findings reveal that transcript buffering functions at a gene-specific level and suggest that cells dynamically adjust RNA splicing, export, and degradation in response to individual RNA synthesis alterations, thereby sustaining cellular homeostasis.

genomics↗

bioRxiv2023

Human milk variation is shaped by maternal genetics and impacts the infant gut microbiome

Human milk is a complex mix of nutritional and bioactive components that provide complete nutrition for the infant. However, we lack a systematic knowledge of the factors shaping milk composition and how milk variation influences infant health. Here, we used multi-omic profiling to characterize interactions between maternal genetics, milk gene expression, milk composition, and the infant fecal microbiome in 242 exclusively breastfeeding mother-infant pairs. We identified 487 genetic loci associated with milk gene expression unique to the lactating mammary gland, including loci that impacted breast cancer risk and human milk oligosaccharide concentration. Integrative analyses uncovered connections between milk gene expression and infant gut microbiome, including an association between the expression of inflammation-related genes with IL-6 concentration in milk and the abundance of Bifidobacteria in the infant gut. Our results show how an improved understanding of the genetics and genomics of human milk connects lactation biology with maternal and infant health.

genomics↗