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Biology subjects

Wang, F.-Y.

Publications and source records attributed to Wang, F.-Y..

3 recordsLinked to original sources

Massive Chromosome Fission and Speciation in Asian River Chub: Integrating Kinetochore Reproduction Theory with Transposable Element Dynamics

Chromosomal speciation poses a paradox: if rearrangements cause postmating isolation, how do they persist and spread? We propose that centromere remodeling, driven by transposable element accumulation, provides a mechanistic solution. In Opsariichthys, a hyper-diverse lineage of Asian river chub with 2N = 76-78 chromosomes, we identify [~]15 fission events coinciding with TE-fueled centromeric DNA expansion, potentially linked to a mutation in the PIWI1 protein. These expansions enable neokinetochore formation, allowing fissioned chromosomes to segregate faithfully, while subsequent rearrangements disrupt pairing and reduce gene flow. Comparative genomics reveals that fissioned chromosomes exhibit lower migration and greater divergence, acting as reproductive barriers. Our findings show that TE-mediated kinetochore duplication can facilitate extensive chromosome fission without meiotic disruption, providing a viable and previously underappreciated path to rapid speciation.

genomics↗

Chromosome-level genome assembly of the loach goby, Rhyacichthys aspro, reveals mechanisms underlying Gobioidei diversification

The percomorph fish clade Gobioidei are a suborder that comprises over 2,200 species distributed in nearly all aquatic habitats. To understand the genetics underlying their diversification, we sequenced and annotated the genome of the loach goby, Rhyacichthys aspro, the basal most group, and compared it with nine additional Gobioidei species. Within Gobioidei, the loach goby possesses the smallest genome at 607 Mb, and a rise in species diversity from basal to derived lineages is mirrored by enlarged genomes and a higher presence of repeat elements (REs), particularly DNA transposons. These transposons are enriched in coding and regulatory regions and their copy number increase is strongly correlated with mutation rate, suggesting that DNA repair after transposon excision/insertion leads to nearby mutations. Consequently, the proliferation of DNA transposons might be the crucial driver of Gobioidei diversification and adaptability. The loach goby genome also points to mechanisms of ecological adaptation. It contains relatively few genes for lateral line development but an over representation of synaptic function genes, with genes putatively under selection linked to synapse organization and calcium signaling, suggesting a sensory system distinct from other Gobioidei species. We also see an overabundance of genes involved in neurocranium development and renal function, adaptations likely connected to its flat morphology suited for strong currents and an amphidromous life cycle. Comparative analyses with hill-stream loaches and the European eel reveal convergent adaptations in body shape and saltwater balance. These findings shed light on the loach gobys survival mechanisms and the broader evolutionary trends within Gobioidei.

genomics↗

Identification of pathogens in culture-negative infective endocarditis with metagenomic analysis

Pathogens identification is critical for the proper diagnosis and precise treatment of infective endocarditis. Although blood and valve cultures are the gold standard for IE pathogens detection, many cases are culture-negative, especially in patients who had received long-term antibiotic treatment, and precise diagnosis has therefore become a major challenge in the clinic. Metagenomic sequencing can provide both information on the pathogenic strain and the antibiotic susceptibility profile of patient samples without culturing, offering a powerful method to deal with culture-negative cases. In this work, we assessed the feasibility of a metagenomic approach to detect the causative pathogens in resected valves from IE patients.\n\nUsing our in-house developed bioinformatics pipeline, we analyzed the sequencing results generated from both next-generation sequencing and Oxford Nanopore Technologies MinION nanopore sequencing for the direct identification of pathogens from the resected valves of seven clinically culture-negative IE patients according to the modified Duke criteria. Moreover, we were able to simultaneously characterize respective antimicrobial resistance features. This provides clinicians with valuable information to diagnose and treat IE patients after valve replacement surgery.

microbiology↗