Biology subjects

Hansen, H.

Publications and source records attributed to Hansen, H..

3 recordsLinked to original sources

bioRxiv2026

Validated microsatellite markers for Gyrodactylus salaris: a toolkit for individual identification and genetic studies

Microsatellite markers remain essential for individual-level genetic work in taxa where genome-wide methods are not yet routinely feasible due to extremely low DNA yields per specimen. In Gyrodactylus, even the most recent reference genomes have required pooling thousands of individuals, leaving a practical gap between genome-scale resources and individual-level analyses. Here we present a genome-informed microsatellite panel, developed by selecting single-copy loci with non-repetitive flanking regions and assembling all markers into a single multiplex PCR. Marker identity and performance were verified via amplification tests, Sanger sequencing, and cross-laboratory genotyping, confirming that the same samples generated identical fragment-size profiles in both laboratories. Long tandem repeats occasionally prevented exact repeat-count determination, yet allele-size classes were discrete and reproducible across replicates. The panel enables rapid individual identification and reliable strain and lineage assignment. It also offers a practical starting point for population-genetic and evolutionary studies that require individual-level data.

genomics↗

bioRxiv2024

The biotoxin BMAA promotes mesenchymal transition in neuroblastoma cells

Mesenchymal-like cancer cells are an indicator of malignant tumors as they exhibit tumorigenic properties including downregulation of differentiation markers, and increased colony-forming potential, motility, and chemoresistance. We have previously demonstrated that the cyanobacterial biotoxin beta-methylamino-L-alanine (BMAA) is capable of influencing neural cell differentiation state through mechanisms involving the Wnt signaling pathway, suggesting the possibility that BMAA may play a role in influencing other Wnt related differentiation processes including mesenchymal transition. In this study we present evidence characterizing the effects of BMAA on mesenchymal transition in a human neuroblastoma cell line and provide support for the hypothesis that the biotoxin can promote this process in these cells by altering differentiation state, inducing changes in gene expression, and changing cellular function in manners consistent with cellular mesenchymal transition. Results of this study indicate that BMAA exposure may promote carcinogenesis through its effects on cell differentiation state in certain contexts. These results suggest that exposure to the biotoxin BMAA may be an influencing factor in chemotherapy resistance and cancer relapse in neuroblastoma.

molecular biology↗

bioRxiv2024

Structural basis for allosteric regulation of human phosphofructokinase-1

Phosphofructokinase-1 (PFK1) catalyzes the rate-limiting step of glycolysis, committing glucose to conversion into cellular energy. PFK1 is highly regulated to respond to the changing energy needs of the cell. In bacteria, the structural basis of PFK1 regulation is a textbook example of allostery; molecular signals of low and high cellular energy promote transition between an active R-state and inactive T-state conformation, respectively. Little is known, however, about the structural basis for regulation of eukaryotic PFK1. Here, we determine structures of the human liver isoform of PFK1 (PFKL) in the R- and T-state by cryoEM, providing insight into eukaryotic PFK1 allosteric regulatory mechanisms. The T-state structure reveals conformational differences between the bacterial and eukaryotic enzyme, the mechanisms of allosteric inhibition by ATP binding at multiple sites, and an autoinhibitory role of the C-terminus in stabilizing the T-state. We also determine structures of PFKL filaments that define the mechanism of higher-order assembly and demonstrate that these structures are necessary for higher-order assembly of PFKL in cells.

biochemistry↗