Marine Life Science & Technology最新文献

The complex current systems of the Southern Ocean play a critical role in shaping the heterogeneity and distinctiveness of Antarctic habitats. Nonetheless, how Antarctic water masses influence ciliates, one of the most common groups of protozoa in polar regions, remains largely unknown. The present study investigated how the ciliate communities are affected by complex Southern Ocean currents by analyzing the diversity distributions, community assembly mechanisms, and co-occurrence networks of ciliates across three distinct water masses in the Scotia Sea. The findings reveal that the hydrography of the Scotia Sea significantly affects the spatial patterns of planktonic ciliates, primarily through the combination of temperature, salinity, and depth. In contract to surface waters (Antarctic Surface Water and Antarctic Circumpolar Current), ciliates inhabiting deep waters (Circumpolar Deep Water) exhibit stronger and more direct correlations with the environment parameters, alongside greater network stability. Community assembly in surface and deep-water masses is governed by stochastic and deterministic processes, respectively. Compared to other Antarctic regions documented in previous studies, the Scotia Sea demonstrated the lowest alpha diversity indices for ciliates while harboring the highest number of endemic species. A detailed re-evaluation of Antarctic ciliate community structure in the Antarctic from prior research offers valuable insights into how dynamic ocean currents shape the ecological dynamics of ciliate communities, thus providing a broader understanding of the environmental changes impacting polar marine ecosystems.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00308-7.

Ciliates in the order Metopida exhibit a global distribution and play essential roles as consumers of and common hosts to prokaryotes in both hypoxic and anoxic environments. Based on detailed morphological and morphometric data of Metopus es and Brachonella contorta, type species of two common and relatively species-rich metopid genera, we investigate the morphogenesis, and molecular phylogeny of each, and analyze the secondary structure of the V9 region of their 18S rRNA gene sequences. The new findings include: (1) These two species present two different stomatogenetic modes, which are stable within their respective genera and each can be regarded as a reliable generic feature for differentiation. (2) Both species share the same outcome regarding the parental oral apparatus, i.e., the old paroral membrane and adoral zone of membranelles are entirely reorganized in situ in the proter. (3) The paroral membrane is diplostichomonadal in the examined isolates, a feature which has long been overlooked and may be enigmatically present in other previously described populations. As concerns their phylogeny, the clear delineation of each species is supported by the high conservation of SSU rRNA gene sequences, and the close phylogenetic clustering, of different populations of each species from geographically distant localities. In agreement with previous phylogenetic studies, the MeBr clade (Metopus, including M. es and marine/brackish Metopus members, and all Brachonella species) is recovered repeatedly with moderate to high support.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00309-6.

Ecological succession is vital for forecasting ecosystem responses to environmental changes and their future states. Zooplankton, a primary natural food source in aquaculture, plays a crucial role in maintaining ecosystem function. Thus, understanding how zooplankton communities respond to environmental changes is essential for economic and ecological outcomes. In this study, we examined three types of aquaculture ponds (crab, crayfish, and fish ponds) with over 10 years of history and analyzed 27 environmental factors potentially influencing zooplankton dynamics throughout the year. Our results showed that Rotifera was the most abundant group in all three pond types, followed by Protista, Cladocera, and Copepoda. The dominant species across different seasons and ponds were Polyarthra vulgaris, Anuraeopsis fissa, and Trichocerca pusilla. The alpha diversity of zooplankton was influenced by various environmental factors across different pond types, with significant effects of antibiotics observed only in the fish ponds. The temporal and spatial distributions of zooplankton communities varied significantly. Deterministic processes, driven primarily by temperature and ammonia nitrogen, were identified as the primary mechanisms influencing zooplankton community assembly in freshwater aquaculture ponds. These findings inform management practices aimed at regulating key environmental drivers and optimizing zooplankton dynamics, with implications for maintaining ecosystem stability and productivity and, ultimately, supporting sustainable aquaculture.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00297-7.

Anammox and denitrification are key processes for nitrogen removal in lake sediments. However, how environmental changes mediate the community structure and functional genes of nitrogen removal bacteria in lakes remain unclear. Using metagenome and amplicon sequencing, we investigated the anammox and denitrifying bacteria and their nitrogen removing potentials in lakes experiencing significant spatiotemporal and environmental variations. The community structure of anammox and denitrifying bacteria exhibited stronger lake-wide spatial variations than that of seasonality, while only the denitrification-related functional genes showed substantial variations in both lakes. Anammox genes (e.g., hzsA/B/C and hdh) showed no significant spatial variations. However, the abundances of anammox and denitrifying genes were significantly higher in winter than in summer. The mesotrophic Lake Weishan demonstrated a greater capacity for complete denitrification in winter, while the eutrophic Lake Donghu exhibited a higher potential of anammox in summer. Differences in functional gene abundances between lakes were more pronounced than variations in phylogenetic diversity, indicating clear functional adaptations to local environments. The coupled nitrogen removal potentials also reflected ecological interactions among anammox and denitrifying genes. Importantly, anammox and denitrifying bacterial communities and their functional genes were primarily driven by dissolved organic carbon, total phosphorous and zinc (Zn). The dissimilarities of anammox and denitrifying bacterial communities increased with geographic distance, indicating a clear distance-decay effect. This study highlights the anammox and denitrifying bacteria and their nitrogen removal potentials in lake sediments that are mediated by both spatial and seasonal environmental changes.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00310-z.

Seven previously unreported sesquiterpenes including three rare 5/5/6-fused tricyclic gymnomitrane-type sesquiterpenes (1-3), an ent-longipinane-type sesquiterpene (4), a cuparane-type sesquiterpene (5), and two chamigrane-type sesquiterpenes (6 and 7), along with a known chamigrane-type sesquiterpene xylariterpenoid C (8) were isolated from the hydrothermal vent sediment derived fungus Penicillium sp. JWM79-5-1. Their structures were identified on the basis of 1D and 2D NMR, in conjunction with Mosher's method, X-ray crystallography, and electronic circular dichroism (ECD). The antithrombotic activity of compounds 1-6 and 8 was evaluated in arachidonic acid (AA)-induced zebrafish thrombosis model in vivo. The results revealed compound 1 with potent antithrombotic activity in a concentration-dependent manner. Further, the pro-angiogenic activities of compounds 1-6 and 8 were evaluated in a transgenic zebrafish model that expresses vegfr2, the receptor for the angiogenic factor VEGF, tagged with the green fluorescence protein (vegfr2-GFP) through detecting the length of both intersegmental vessels (ISVs) and subintestinal veins (SIVs). The results revealed that compound 1 exhibited a potent antithrombotic activity while 3 revealed a potent pro-angiogenic activity. These findings strongly support drug development of these compounds in cardiovascular disease treatment.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00303-y.

Mongolian gerbils had high ability to endure both high and cold temperatures. To study the mechanism of high ability for thermal adaptation, gerbils were acclimated to high temperature (30 °C) for 8 weeks, and were measured for metabolic features, body composition as well as mitochondrial content and activities. Lipidomic techniques were used to measure changes in mitochondrial membrane, including potential mitochondrial membrane remodeling during acute thermoregulation in gerbils. Heat acclimated gerbils showed lower basal metabolic rates but no changes in adaptive non-shivering thermogenesis were detected. A significant mitochondrial membrane remodeling with increases in monounsaturated/polyunsaturated free fatty acids ratios was associated with the decrease in metabolic rate. During heat acclimation, mitochondrial cytochrome C oxidase activity was elevated in brown adipose tissue, presumably caused by the increase in membrane unsaturation. Our results indicated that mitochondrial membrane remodeling is an important mechanism during heat acclimation in Mongolian gerbils, to reduce the metabolic rate in general while preserving sufficient capability to respond to acute cold. Such a mechanism may allow gerbils to cooperate with wide range of daily and seasonal temperature fluctuations.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00317-6.

To promote sustainable aquaculture, plant-based ingredients are increasingly replacing fish meal (FM) and fish oil (FO) in aquafeeds, altering broodstock diets and reducing omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFAs), essential for reproductive success and progeny growth. Despite the critical role of ω-3 LC-PUFAs, particularly docosahexaenoic acid (DHA) in brain function, data on how fry cope with FM/FO-free diets during early development remain limited. To address this, we conducted a 2-year experiment comparing three broodstock diets: a commercial diet (C diet), a total plant-based diet (V1 diet), and a plant-based diet supplemented with DHA-rich Schizochytrium sp. microalgae oil (V2 diet). After reproduction, progeny were fed either a C diet or a plant-based diet (V). Six groups (C-C, C-V, V1-C, V1-V, V2-C, V2-V) were analyzed for survival, feed intake, and growth, as well as neuropeptide, neurotransmitter, and intestinal hormone expression. Results showed enhanced robustness in fry-fed V diets, particularly from V1 and V2-fed broodstock, with improved survival and feed intake. Fry from DHA-supplemented broodstock (V2-V) compensated for initial growth delays, achieving growth comparable to fry from commercial-fed mothers (C-V) within 30 days. Neurophysiological and gut-brain adaptations revealed complex compensatory mechanisms enabling fish to thrive on sustainable diets. These findings highlight the potential of DHA supplementation in plant-based diets to support sustainable aquaculture and warrant further validation under diverse nutritional and environmental conditions.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00316-7.

The distribution of Pampus argenteus (Euphrasen, 1788) spans a pronounced latitudinal-environmental gradient from the subtropical to the subpolar zones. The species is reported to have multiple stocks along coastal China, exhibiting different spawning behaviors and habitat preferences. Such ecological variations might imply potential genetic divergence and local adaptation. We resequenced 117 genomes from six coastal stocks of P. argenteus in China. Although no hierarchical genetic structure was identified, over 50% of the single-nucleotide polymorphisms (SNPs) indicated moderate to strong divergence in at least two stocks. The Mantel test identified 21 100-kb sliding windows with significant isolation by distance and environment, while a majority did not. Given the lack of genome-wide isolation by distance, the 21 windows may be under selection pressure from the latitudinal-environmental variations. Among the 21 windows, certain genes were linked to circadian clock regulation and thermal stress response, suggesting sea surface temperature and sunshine duration as selective forces. A total of 17 genes regulated neuron activity; variations near these genes might subsequently shape the different spawning and migratory behaviors among the stocks. Additionally, 1204 SNPs were mapped to non-coding regions; 14 transcriptional and translational factors were identified in the 21 windows. These findings imply that alterations in gene expression might contribute to the local adaptation of the P. argenteus stocks.

Supplementary information: The online version contains supplementary material available at 10.1007/s42995-025-00312-x.

The Indo-Australian Archipelago (IAA) is the world's preeminent marine biodiversity hotspot, distinguished by its exceptional species richness in tropical shallow waters. This biodiversity has spurred extensive research into its evolutionary and biogeographic origins. Two prominent theoretical frameworks dominate explanations for the IAA's biodiversity: the "centers-of hypotheses" and the "hopping hotspot hypothesis". The "centers-of hypotheses" posits that specific regions serve as key sources of IAA biodiversity, either through the accumulation and overlap of species from external areas or via elevated rates of local speciation. In contrast, the "hopping hotspot hypothesis" asserts that biodiversity hotspots are dynamic, shifting across geological timescales in response to tectonic and environmental changes. This review synthesizes these contrasting perspectives into an integrated framework, the "Dynamic Centers Hypothesis," which proposes that as biodiversity hotspots migrate over time, the IAA's role in generating and sustaining biodiversity has evolved, with varying contributions from different sources dominating distinct historical phases. By synthesizing the evidence for both hypotheses and incorporating recent findings, including fossil and phylogeography data, we propose the "Dynamic Centers Hypothesis" as a comprehensive and unifying explanation for the IAA's biodiversity. The review further explores biogeographic delineation, aligning tropical marine realms with the IAA's evolutionary trajectory, from its Tethyan roots to its modern Indo-West Pacific dominance. Looking forward, advances in DNA barcoding and genomics are uncovering vast cryptic diversity, revolutionizing our comprehension of IAA phylogeographic history. These discoveries underscore the imperative for a multidimensional conservation framework, integrating phylogenetic, and functional diversity, to preserve this biodiversity hotspot amid escalating global change.