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The Chinese tapertail anchovy, Coilia nasus, is a socioeconomically important anadromous fish that migrates from near ocean waters to freshwater to spawn every spring. The analysis of genomic architecture and information of C. nasus were hindered by the previously released versions of reference genomes with gaps. Here, we report the assembly of a chromosome-level gap-free genome of C. nasus by incorporating high-coverage and accurate long-read sequence data with multiple assembly strategies. All 24 chromosomes were assembled without gaps, representing the highest completeness and assembly quality. We assembled the genome with a size of 851.67 Mb and used BUSCO to estimate the completeness of the assembly as 92.5%. Using a combination of de novo prediction, protein homology and RNA-seq annotation, 21,900 genes were functionally annotated, representing 99.68% of the total predicted protein-coding genes. The availability of gap-free reference genomes for C. nasus will provide the opportunity for understanding genome structure and function, and will also lay a solid foundation for further management and conservation of this important species. Measurement(s) Coilia nasus • Gap-free genome assembly • sequence annotation Technology Type(s) DNBSEQ • Pacbio HiFi Sequencing • Nanopore Sequencing • Hi-C Sample Characteristic - Organism Coilia nasus Sample Characteristic - Environment freshwater Sample Characteristic - Location Taizhou City, Jiangsu Province, China [ABSTRACT FROM AUTHOR]

In the present work, polydopamine nanotubes (PDA NTs) decorated with silver (Ag) nanoparticles (NPs) were successfully fabricated via a template induced self-polymerization of dopamine, followed by in situ reduction and immobilization of NPs from nitrate solution. The typical Ag@PDA NTs exhibits 39.1 wt % of Ag content and excellent catalytic activity as demonstrated by the reduction of a model organic pollutant, methylene blue, with an apparent rate constant of 3.19 min–1 in the first-order kinetics model, which is the highest value reported so far. The superior catalytic performance is attributed to the high Ag loading, uniform distribution of NPs, and excellent dispersity in water. Moreover, it is believed that the superhydrophilic hollow morphology of PDA NTs with ultrahigh porosity (81.4%) and open ends facilitates the contact of the catalysts with reactant molecules and mass transfer in aqueous reaction. The Ag@PDA NTs nanocatalysts could be easily recycled, and the catalytic efficiency remained nearly unchanged over 10 cycles. This synthetic strategy was proved to be applicable to other typical metal catalysts (e.g., Pt, Pd, Au). This work presents a universal approach to fabricate highly efficient nanocatalysts with PDA NTs as supports used for the reduction and degradation of organic dyes. [ABSTRACT FROM AUTHOR]

The Chinese soft-shelled turtle (Trionyx sinensis) is endemic to China and is one of the most abundant edible turtle in Southeast Asia. The genetic resources of the species sharply degraded for arbitrary artificial propagation and farming and overfishing wild population. As a result, the turtle has been listed as Vulnerable on the IUCN Red List. In this study, 20 polymorphic microsatellite loci were isolated and characterized in a stock through biotinylated probes for hybridization and library screening. The number of alleles varies between 7 and 18, and the observed and expected heterozygosity at the population level ranged from 0.2220 to 0.8333 and 0.7635 to 0.9431, respectively, and only a single locus deviated significantly from Hardy-Weinberg equilibrium (P < 0.01). These microsatellite markers could prove useful for genetic identification and population management of Chinese soft-shelled turtle for natural resources recovery in the future. [ABSTRACT FROM AUTHOR]

Background: The Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis, YFP) and the East Asian finless porpoise (Neophocaena asiaeorientalis sunameri, EFP) are 2 subspecies of the narrow-ridged finless porpoise that live in freshwater and saltwater, respectively. The main objective of this study was to provide contiguous chromosome-level genome assemblies for YFP and EFP., Results: Here, we generated and upgraded the genomes of YFP and EFP at the telomere-to-telomere level through the integration of PacBio HiFi long reads, ultra-long ONT reads, and Hi-C sequencing data with a total size of 2.48 Gb and 2.50 Gb, respectively. The scaffold N50 of 2 genomes was 125.12 Mb (YFP) and 128 Mb (EFP) with 1 contig for 1 chromosome. The telomere repeat and centromere position were clearly identified in both YFP and EFP genomes. In total, 5,480 newfound genes were detected in the YFP genome, including 56 genes located in the newly identified centromere regions. Additionally, synteny blocks, structural similarities, phylogenetic relationships, gene family expansion, and inference of selection were studied in connection with the genomes of other related mammals., Conclusions: Our research findings provide evidence for the gradual adaptation of EFP in a marine environment and the potential sensitivity of YFP to genetic damage. Compared to the 34 cetacean genomes sourced from public databases, the 2 new assemblies demonstrate superior continuity with the longest contig N50 and scaffold N50 values, as well as the lowest number of contigs. The improvement of telomere-to-telomere gap-free reference genome resources supports conservation genetics and population management for finless porpoises., (© The Author(s) 2024. Published by Oxford University Press GigaScience.)