Biology subjects

Scholten, J.

Publications and source records attributed to Scholten, J..

3 recordsLinked to original sources

bioRxiv2025

Cytogenetic constraints on hybridization: A meta-analysis investigating the role of chromosome number in monocot hybrid evolution using a newly developed tool, the ploidy deviation index (PDI).

Background and aimsHybridization is a major driver of plant diversity, yet the role of cytogenetic compatibility, particularly differences in chromosome number, remains poorly understood. Differences in parental chromosome number can present barriers to hybrid formation by disrupting meiotic stability, but the extent to which biological and ecological factors influence the chromosomal architecture of hybrids remains poorly quantified, especially in monocots. This study aims to investigate how chromosome number divergence interacts with biological and ecological factors to shape hybrid formation in monocots, using a novel quantitative metric, the Ploidy Deviation Index (PDI), to standardize comparisons of hybrid cytogenetic architecture. Material and methodsWe developed and applied the PDI, a continuous index quantifying chromosome-number deviation between a hybrid and its two parents, across approximately 200 hybrid cases with documented parental karyotypes. Hybrids were categorized as homoploid, uniparentally homoploid, intermediate, or polyploid based on their PDI values. We analyzed the distribution of PDI scores in relation to type of hybrid origin (natural vs. artificial), growth habit, size of the genus (a proxy for richness), and range of chromosome number within a genus (proxy for diversity). Comparisons across categories employed Anderson-Darling k-sample tests, multinomial logistic regression, and Mann-Whitney U tests to determine significance. Key resultsHomoploid hybrids were found to be the most frequent. We found no significant difference in PDI distributions between natural and artificial hybrids. Significant variation in PDI distributions was found among growth habits, with aquatic hybrids more likely to be homoploid and geophytic hybrids showing higher proportions of polyploidy. Intermediate hybrids were common in larger genera with broader chromosome-number ranges, whereas polyploid hybrids showed the highest PDI values in large and karyotypically diverse genera. ConclusionThese results challenge long-held assumptions that polyploidy dominates hybrid formation and reveal that homoploid and intermediate chromosomal configurations are common in monocots. The PDI framework offers a powerful, standardized approach for assessing cytogenetic constraints on hybridization, with implications for systematics, evolutionary biology, and conservation.

plant biology↗

bioRxiv2025

The power to resolve relationships: identifying incongruence and precision of reduced representation and genome-wide data in phylogenomics and population genomics

Target capture of ultraconserved elements (UCEs) and taxon-specific probes are widely used reduced-representation methods in phylogenomics and, increasingly, in population genomics for their ability to retrieve hundreds to thousands of homologous loci across divergent taxa. Meanwhile, declining costs and improved computational methods have made genome resequencing more accessible for non-model species, enabling the generation of datasets that can address evolutionary and ecological questions from micro- to macroevolutionary scales. Whether target capture approaches to likewise generate datasets that can address questions across broad hierarchical scales remains unclear. Here, we assess the efficacy of data collection (i.e., single nucleotide polymorphism (SNP) retention), predicted genetic variation across samples (i.e., heterozygosity), and phylogenetic congruence between data generated using reduced-representation methods and genome resequencing, leveraging publicly available datasets from plants and animals. We found that SNP retention varied by locus type, with genome-wide datasets retaining the highest proportion of SNPs and UCEs the lowest proportion. Heterozygosity also differed, with Benchmarking Universal Single-Copy Orthologs (BUSCOs) producing the lowest estimates, followed by UCEs; the inclusion of supercontig flanking regions raised heterozygosity values moderately. Across all phylogenetic trees, UCE datasets had the lowest bootstrap support, followed by BUSCOs and single copy orthologous genes. Population structure analyses frequently underestimated the number of ancestral populations in reduced-representation datasets, often identifying fewer populations than genome-wide datasets and assigning samples to different clusters. These discrepancies underscore the challenges of relying solely on reduced-representation methods for robust inferences of genetic diversity, phylogenetic relationships, and population structure.

evolutionary biology↗

bioRxiv2024

The Mag-Click-Capture-Release Technology for Selective Capture and Release of Hepatocyte-Derived Extracellular Vesicles as Biomarkers for Liver Disease

Chronic liver diseases, such as liver cirrhosis and hepatocellular carcinoma (HCC), present major global health challenges, often diagnosed late. Circulating extracellular vesicles (EVs), which carry disease-specific biomolecular cargo, is emerging as an early diagnostic and prognostic biomarker for several diseases including cancer. However, current EV purification methods including ultracentrifugation and size exclusion chromatography present several limitations. Here, we present the Mag-Click-Capture-Release Technology for selective capture and release of EVs that combines magnetic beads, trans-cyclooctene (TCO) and tetrazine (Tz) click chemistry, immuno(antibody)-based capture and disulfide-driven release of EVs. Importantly, the Mag-Click-Capture-Release Technology is customizable, whereby using specific antibodies conjugated to TCO antibodies, different EV subtypes can be selectively captured and released for further analysis. With our Mag-Click-Capture-Release Technology, we successfully isolated hepatocyte-derived EVs from human serum with good recovery, high specificity and purity when compared with standard ultracentrifugation. Validation in serum samples obtained from cirrhosis and HCC patients with alcohol-associated liver disease evidenced an increasing trend in hepatocyte-EV levels correlating with disease severity, suggesting potential for early diagnosis and prognosis. In conclusion, we present here the Mag-Click-Capture-Release Technology, a customizable and efficient approach for selective isolation of organ-, cell-specific, and disease-relevant EVs from biological samples that can be subsequently released for downstream molecular EV analysis and EV-related functional assays.

bioengineering↗