Marine Life Science & Technology最新文献

Urochordate Ciona spp. are ideal marine model organisms for studying embryogenesis and developmental and evolutionary biology. However, the effective implementation of genetic labeling and CRISPR/Cas9-based editing tools at cellular resolution remains challenging. This study successfully developed and validated a collection of Gateway-based vectors for cell labeling in Ciona spp. The destination vector sets contained two Gateway cassettes flanked by Minos sites, allowing the N- or C-terminal tagging of a protein of interest with various fluorescent markers. In addition, we optimized the CRISPR/Cas9 and CRISPR/dCas9 systems by incorporating P2A-mCherry, a fluorescent indicator for Cas9 expression at cellular resolution. We demonstrated the effective destruction or inhibition of target genes when CRISPR constructs were introduced into fertilized eggs. Furthermore, we engineered a dual fluorescence sensor system that helps visualize successful gene knockouts at the cellular level in specific tissues. The genetic tools developed in this study offer a robust method for gene expression, cell tracking, and subcellular protein localization while also facilitating tissue-specific functional analysis in Ciona embryos and other model systems.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00300-1.

Although anisotropic NMR spectroscopy has emerged as a powerful method for determining the relative configuration of complex natural products, major challenges persist with structurally flexible molecules. In this study, we conducted a systematic comparative analysis of stereochemical elucidation, combining anisotropic NMR spectroscopy and density functional theory (DFT) calculations on spiroepicoccin B (1) and epicoccin V (2), which were characterized as thiodiketopiperazine marine natural products isolated from the deep-sea-derived fungus Epicoccum nigrum SD-388. For the flexible compound 2, we compared various conformational sampling approaches, including an assessment of the quality of relative energies within the obtained ensembles. We demonstrated the critical role of dispersion correction within DFT computations to precisely account for weak non-bonded intramolecular interactions. By integrating anisotropic NMR analysis, chemical shifts, electronic circular dichroism, and DFT computations, we determined the absolute configurations and conformational ensembles for 1 and 2, respectively, highlighting the significance of the intramolecular methyl-π interaction in stabilizing one of the conformers. Our study introduces new strategies to address conformational flexibility in the stereochemical elucidation of challenging organic molecules.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00294-w.

The sea-land transition is one of the most dramatic evolutionary changes and requires an adaptive genetic response to salinity changes and osmotic stress. Here, we used multi-species genomes and multi-tissue transcriptomes of the talitrid crustaceans, a living sea-land transition model, to investigate the adaptive genetic changes and osmoregulatory organs that facilitated their salinity adaptation. Genomic analyses detected numerous osmoregulatory genes in terrestrial talitrids undergoing gene family expansions and positive selection. Gene expression comparisons among species and tissues confirmed the gill being the primary organ responsible for ion transport and identified the genetic expression variation that enable talitrids to adapt to marine and land habitats. V-type H⁺-ATPases related to H⁺ transport play a crucial role in land adaptations, while genes related to the transport of inorganic ions (Na⁺, K⁺, Cl^-) are upregulated in marine habitats. Our results demonstrate that talitrids have divergent genetic responses to salinity change that led to the uptake or excretion of ions in the gills and promoted habitat adaptation. These findings suggest that detecting gene expression changes in talitrids presents promising potential as a biomarker for salinity monitoring.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00298-6.

Methanogenic endosymbionts are the only known intracellular archaeans and are especially common in anaerobic ciliated protists. Studies on the evolution of associations between anaerobic ciliates and their methanogenic endosymbionts offer an excellent opportunity to broaden our knowledge about symbiosis theory and adaptation of eukaryotes to anoxic environments. Here, the diversity of methanogenic endosymbionts was analyzed with the addition of nine anaerobic ciliate populations that were newly studied by various methods. Results showed that diverse anaerobic ciliates host methanogenic endosymbionts that are limited to a few genera in orders Methanomicrobiales, Methanobacteriales, and Methanosarcinales. For the first time, anaerobic ciliates of the classes Muranotrichea and Prostomatea were found to host methanogenic endosymbionts. Distinct origins of endosymbiosis were revealed for classes Armophorea and Plagiopylea. We posit that armophoreans and plagiopyleans might have harbored Methanoregula (order Methanomicrobiales) and Methanocorpusculum (order Methanomicrobiales), respectively, as methanogenic endosymbionts at the beginning of their evolution. Subsequently, independent endosymbiont replacement events occurred in methanogen-ciliate associations, probably due to ecological transitions, species radiation of ciliate hosts, and vertical transmission bottlenecks of endosymbionts. Our results shed light on the evolution of associations between anaerobic ciliates and methanogens, and identifies the necessary preconditions for illustrating mechanisms by which endosymbioses between these partners were established.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00295-9.

The queen snapper (Etelis oculatus Valenciennes in Cuvier & Valenciennes, 1828) is a deep-sea snapper whose commercial importance continues to increase in the US Caribbean. However, little is known about the biology and ecology of this species. In this study, the presence of a fine-scale population structure and genetic diversity of queen snapper from Puerto Rico was assessed through 16,188 SNPs derived from the Restriction site Associated DNA Sequencing (RAD-Seq) technique. Summary statistics estimated low genetic diversity (HO = 0.333-0.264) and did not reveal population differentiation within our samples (F _ST = - 0.001-0.025). Principal component analysis and a model-based clustering method did not detect a fine-scale subpopulation structure among sampling sites, however, there was genetic variability within regions and sites. Our results have revealed comparable genetic and dispersal patterns to those observed in other shallow-water snapper species in Puerto Rico waters. It is crucial to further enhance our understanding of the ecological and biological aspect of the queen snapper to effectively manage and conserve this species as fishing pressure has been extended to deep water species in the US Caribbean.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00289-7.

Sex determination and differentiation play crucial biological roles in sexual reproduction in vertebrates, including zebrafish. Nevertheless, the intricate molecular mechanisms governing these processes have remained enigmatic. In this study, we showed a pivotal role played by zinc finger GATA-like protein-1 (Zglp-1) in sex differentiation in zebrafish. Our findings revealed that homozygous mutants having no Zglp-1 exhibited a female-to-male sex reversal, ultimately resulting in the development of fertile males. Within the pivotal phase of sexual differentiation, zglp-1 ^-/- zebrafish demonstrated a gene expression pattern that was skewed toward a male phenotype. Notably, the expression of amh was upregulated, while the expression of cyp19a1a was not sustained. Furthermore, our data revealed a direct interaction between the zinc fingers of Zglp-1 and Sf-1, which inhibited the ability of Sf-1 to activate the amh promoter. This interaction was crucial for regulating sex differentiation. Moreover, we observed alterations in gonadal cell proliferation and apoptosis in zglp-1 ^-/- zebrafish, which partially contributed to the sexual fate selection. Overall, our findings firmly established Zglp-1 as a crucial regulator of sex differentiation in zebrafish, offering deep insights into the intricate molecular mechanisms that govern sex determination and differentiation in vertebrates.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00299-5.

Small cell lung cancer (SCLC) is a high-grade malignancy and prone to drug resistance, with limited progress in patient survival over the past 30 years. Therefore, there is an urgent need to explore new treatment strategies for SCLC patients. Autophagic cell death represents a novel therapeutic strategy for cancer cells with high apoptotic thresholds. Here, we demonstrate that nitrobenzoyl-insulicolide A (1), a new sesquiterpene, isolated from Antarctica sponge-derived fungus Aspergillus insulicola HDN151418, inhibits the proliferation of various SCLC cells including adriamycin- or cisplatin/etoposide-resistant cells, via autophagic death rather than apoptosis, necrosis and cell aging. Molecular mechanism analysis revealed that compound 1 induced autophagic cell death in the NCI-H446 and H69 AR cells dependent on activations of the AKT/mTOR/PARP and ERK1/2 signaling pathways. These findings provide an experimental basis for the further development of 1 as a lead compound against small cell lung cancer in future.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00292-y.

Carbohydrate-induced glycogenic hepatopathy is underdiagnosed and difficult to discriminate from hepatic steatosis in humans. The present study used liver biopsy and other diagnostic tools, and adopted metabolomic technology to identify glycogenic hepatopathy rather than hepatic steatosis in largemouth bass induced by high carbohydrate diet (HC). HC induced obvious liver injury in largemouth bass with disarranged hepatocytes, partial cell membrane damage, and irregular distribution of nuclei, accompanied by increased serum ALT and AST activities. PAS staining and glycogen content analysis detected significant increases in liver glycogen content, whereas intrahepatic triglyceride content and programmed cell death were not affected. Metabolomic analysis indicated that up-regulated metabolites were mainly enriched in glycogen synthesis precursors, whereas betaine and unsaturated fatty acids were down-regulated, confirming that HC induced glycogenic hepatopathy rather than hepatic steatosis in largemouth bass. The significantly decreased betaine in both serum and liver of largemouth bass served as a potential key regulator in such disease, whose supplementation could alleviate HC-induced liver injury and serum ALT activity. Betaine supplementation increased betaine and carnitine contents in liver and serum, resulting in decreased hepatic glycogen deposition and cortisol content in largemouth bass. Further study showed that dietary betaine significantly improved the capacity of largemouth bass to resist against ammonia stress. Therefore, our study established a glycogenic hepatopathy-inducing and evaluation model in a primitive teleost and also identified the betaine as the key metabolic marker and prevent strategy, which help advance the understanding of human liver diseases.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00301-0.

Habitat fragmentation is a major cause of biodiversity loss. Fragmentation can alter thermal conditions on the remaining patches, especially at habitat edges, but few studies have examined variations in thermal tolerance of species in fragmented habitats. Ants are sensitive to both habitat fragmentation and temperature changes, and are an ideal taxon for studying these impacts. Here, we focused on the dimorphic ant species Pheidole nodus in a fragmented habitat island system (Thousand island lake) in China. We assessed critical thermal maximum (CTmax), minimum (CTmin), and range (CTrange) temperatures for both minor (workers) and major workers (soldiers) of 2307 individuals from 117 edge and interior colonies across 9 islands during relatively hot and cold seasons. Using mixed-effect linear models, we explored the effects of island area, habitat type (edge vs. interior), season, and caste (worker vs. soldier) on CTmax, CTmin, and CTrange. We found temperatures were 1-3 °C higher in edge than interior sites in relatively hot season. Yet, only CTmax and CTrange in edge populations were higher than those of interior sites on smaller islands. CTmax was higher in relatively hot season and CTmin was lower in relatively cold season, indicating seasonal plasticity in thermal tolerance. Workers consistently had higher CTmax and lower CTmin than soldiers. These findings underscore the importance of seasonality, worker caste, and interactive effect between island area and habitat type in shaping thermal tolerance of a dominant dimorphic ant species on fragmented habitat islands. Our study provides a roadmap for integrating thermal biology into studies of how fragmentation impacts biodiversity.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00288-8.

Phycobilisomes (PBS), the primary light-harvesting complexes in cyanobacteria, are degraded under nitrogen starvation to provide nitrogen for cell growth. This study reveals that carbon supply is a critical prerequisite for PBS degradation under nitrogen deficiency in Synechococcus sp. PCC 7002. Even under nitrogen-deficient conditions, PBS degradation is inhibited in the absence of sufficient carbon. We demonstrate that both the nblAB-mediated PBS-degradation pathway and the ccmLMNK operon-mediated CO₂-concentrating mechanism are essential for PBS degradation. Furthermore, our findings highlight the critical role of PBS degradation in cyanobacterial adaptation to high C/N conditions. Mutant strains (Mut-nblA and Mut-nblB) deficient in PBS degradation exhibited impaired adaptation to high C/N conditions, as evidenced by their inability to thrive in high NaHCO₃ (nitrogen-free) or CO₂ (low-nitrogen) environments. While these mutants displayed a greener phenotype under high C/N conditions compared to the wild type, they exhibited extensive cellular damage, and significant downregulation of photosynthesis-related genes. These results provide novel insights into the carbon-dependent regulation of PBS degradation and its essential role in cyanobacterial C/N balance, highlighting its significance for their adaptation to fluctuating environmental conditions.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00290-0.