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Summary: Natural silks are renewable proteins with impressive mechanical properties and biocompatibility that are useful in various fields. However, the cellular and spatial organization of silk-secreting organs remains unclear. Here, we combined single-nucleus and spatially resolved transcriptomics to systematically map the cellular and spatial composition of the silk glands (SGs) of mulberry silkworms late in larval development. This approach allowed us to profile SG cell types and cell state dynamics and identify regulatory networks and cell-cell communication related to efficient silk protein synthesis; key markers were validated via transgenic approaches. Notably, we demonstrated the indispensable role of the ecdysone receptor (ultraspiracle) in regulating endoreplication in SG cells. Our atlas presents the results of spatiotemporal analysis of silk-secreting organ architecture late in larval development; this atlas provides a valuable reference for elucidating the mechanism of efficient silk protein synthesis and developing sustainable products made from natural silk.

Coral reef fish are important groups of coral reefs, which have great economic and ecological value. Meiji Reef is a representative tropical semi-enclosed atoll in the South China Sea, with rich fish resources. Based on the data from hand-fishing, line-fishing, and gillnet surveys of fish in Meiji Reef from 1998 to 2018, this study summarized the fish species list of Meiji Reef and analyzed the species composition, inclusion index at the taxonomic level (TINCL), genus–family diversity index (G–F index), average taxonomic distinctness index (Δ+), and variation in taxonomic distinctness (Λ+) and their changes. The results revealed that from 1998 to 2018, there were 166 reef-dwelling fish species on Meiji Reef, belonging to 69 genera, 33 families, and 11 orders, of which 128 species were from 20 families of Perciformes, accounting for 77.10% of the total cataloged species. Regarding the dependence of fish on coral reefs, there were 155 reef-dependent species or resident species (accounting for 93.37%) and 11 reef-independent species or wandering species (accounting for 6.63%). The TINCL of the order, families, and genus of fish in Meiji Reef were very high. The genus diversity index (G index), family diversity index (F index), and G–F index of fish in Meiji Reef were very high, and the G index of fish in Meiji Reef in 1998–1999 was higher than that in 2016–2018. The Δ+ and Λ+ values of fish in Meiji Reef from 1998 to 2018 were 56.1 and 148.5, respectively. Compared with 1998–1999, Δ+ and Λ+ of fish increased during 2016–2018, reflecting that the relatives of fish in Meiji Reef became further distant, and the uniformity of taxonomic relationships among species decreased. The research findings indicated that fish exhibited a high taxonomic diversity in Meiji Reef; however, it also revealed significant fluctuations in the fish diversity of Meiji Reef over an extended period, emphasizing the urgent need for timely protection measures. This investigation significantly contributes to our comprehension of the intricate dynamics governing fish species within Meiji Reef and holds broader implications for biodiversity conservation in tropical marine ecosystems.

Under the background of marine strategy and clean energy strategy, China has carried out large-scale construction around marine ranching and offshore wind farms and made great achievements. However, the problems such as high project cost, the fragmentation of marine habitats and maritime conflict are becoming increasingly prominent, which have led to the test and exploration of integrated development of offshore wind farms and marine ranching at home and abroad. Based on the analysis of relevant research and test work at home and abroad, suggestions are put forward for the current situation of integrated development of offshore wind and animal husbandry, as well as the difficulties and challenges in economic and policy feasibility, site selection and planning, fish species selection, supporting equipment development, ecological impact assessment (noise, electromagnetic field, base interference, heavy metal migration, etc.), etc.

The diel vertical migration of mesopelagic fishes in the southern (S-May station and S-Nov station) and central (C-Jun station and C-Dec station) South China Sea was investigated through a series of continuous field surveys conducted in May, June, November, and December 2017. These surveys employed a combination of mid-water trawl and acoustics techniques. The diel migration process, vertical distribution, acoustic migration proportion, and migration pattern of mesopelagic fishes were analyzed. The results revealed that mesopelagic fishes initiated an upward migration before sunset, with the process concluding within 30–120 min after dark. Subsequently, they commenced a downward migration before dawn, which terminated within 10–50 min after sunrise. The mesopelagic deep-sea layers of mesopelagic fishes at the S-May, S-Nov, C-Jun, and C-Dec stations ranged from 360 to 700 m, 350 to 680 m, 350 to 520 m, and 300 to 700 m, respectively. The acoustic migration proportions of mesopelagic fishes at the corresponding stations were found to be approximately 44.5%, 25.7%, 29.8%, and 58.0%, respectively. There were seasonal and regional differences in the vertical migration and distribution patterns of mesopelagic fishes in the South China Sea. A total of 228 species were identified, including 203 fish species, 23 cephalopod species, and 2 shark species. Among these, a subset of 43 fish and cephalopod species exhibited extensive diel vertical migrating behavior. Specifically, this subset comprised 23 lanternfish species, 8 cephalopod species, and 12 other fish species. Lanternfishes were the predominant diel vertical migratory species, while cephalopods also played a significant role in diel vertical migration. The diel migration behavior was found to be slight for Diaphus lucidus, Melamphaes microps, Argyropelecus affinis, and six other fish species. Non-migratory behavior was observed in Sternoptyx obscura, Argyropelecus sladeni, Sternoptyx diaphana, and 13 other fish species. The diel migration habits of 178 additional species of fish, cephalopods, and sharks could not be definitively determined.

Abstract Background Non-small cell lung cancer (NSCLC) is the most common lung cancer with high mortality across the world, but it is challenging to develop an effective therapy for NSCLC. Celastrol is a natural bioactive compound, which has been found to possess potential antitumor activity. However, the underlying molecular mechanisms of celastrol activity in NSCLC remain elusive. Methods Cellular function assays were performed to study the suppressive role of celastrol in human NSCLC cells (H460, PC-9, and H520) and human bronchial epithelial cells BEAS-2B. Cell apoptosis levels were analyzed by flow cytometry, Hoechst 33342, caspase-3 activity analysis, and western blot analysis. Intracellular reactive oxygen species (ROS) were analyzed by flow cytometry and fluorescence microscope. Expression levels of endoplasmic reticulum (ER) stress-related proteins and phosphorylated signal transducer and activator of transcription 3 (P-STAT3) were identified via western blot analysis. A heterograft model in nude mice was employed to evaluate the effect of celastrol in vivo. Results Celastrol suppressed the growth, proliferation, and metastasis of NSCLC cells. Celastrol significantly increased the level of intracellular ROS; thus, triggering the activation of the ER stress pathway and inhibition of the P-STAT3 pathway, and eventually leading to cell apoptosis, and the effects were reversed by the pre-treatment with N-Acetyl-l-cysteine (NAC). Celastrol also suppressed tumor growth in vivo. Conclusion The outcomes revealed that celastrol plays a potent suppressive role in NSCLC in vitro and in vivo. Celastrol induces apoptosis via causing mitochondrial ROS accumulation to suppress the STAT3 pathway. Celastrol may have potential application prospects in the therapy of NSCLC.

To build a maritime power, the implementation of the strategy of sustainable marine development and revitalization of islands is one of the major issues in China. Now, the advancement of China’s "The Belt and Road initiative" construction and the strategic deployment of the Guangdong-Hong Kong-Macao Greater Bay Area and Hainan Free Trade Port have brought great opportunities for the development of large-scale island regions. Zhoushan archipelago is the largest archipelago in China, located in the Yangtze River Estuary. It is the intersection of the national strategy for the integrated development of the Yangtze River Delta and the international archipelago new area, which has great space for development and significance of exploration to construct a global marine center city. This paper was aiming at the national strategic positioning, discussing its existing problems, and putting forward countermeasures and suggestions to promote the comprehensive development of Zhoushan Islands in combination with the successful development experience of foreign islands, based on the analysis of Zhoushan Islands' geographical location, resources and environment, ecosystem, cultural and historical status. And suggestions on the research direction of priority attention to marine ecological civilization, integrated development of watersheds with sea and land, and smart green port construction from the perspective of interdisciplinary were also put forward, so as to enrich the scientific and technical connotation of important windows and to provide reference for the implementation of the plan during the fourteenth five-year plan for Zhoushan Islands.

Fishes play significant ecological functions though many ways in coral reef, and feeding process is one of the most important. To understand responses of reef fish communities to external disturbances, we studied variations in trophic groups of fishes in the lagoon of Meiji Reef in the South China Sea based on fish specimens collected by hand-line and gillnet in 1998—2018, databases and literatures. Differences in species richness, abundance, weight and size of fish in different trophic groups among years were analysed, especially herbivorous and high-economy fish. The results indicated that the percentages of species number and weight of herbivores, piscivores and detritivores decreased significantly from 1998—1999/2016—2018. Herbivorous fishes saw the biggest decline. In the gillnet surveys, the percentages of species number and weight of herbivorous fishes in 1999 were 33.33% and 56.14%, respectively, while the percentages in 2016—2018 were all zero. The species number percentage of large-sized fishes (maximum total length ≥ 65 cm) in 1998—1999 was significantly larger than that in 2016—2018. Thirty-two fish species being found in the lagoon of Meiji Reef during 1998—1999 were not discovered during 2012—2018. Contingency table analysis showed that the disappearance of fish was not significantly related to the vulnerability or resilience of fish rather than economic value. The mean body weight of very high & high-value fish in 1998—1999 was significantly larger than that in 2016—2018. Simple linear regression showed that coral cover had the greater effect on the species number and weight of herbivorous fishes as compare to fishing power. Both fishing power and coral cover had significant effects on the mean body weight. To protect fish on Meiji Reef, we propose to strengthen the conservation initiatives (e.g., creating protected areas, prohibiting fishing, and reconstructing habitat).

The decline of coral reefs and their fish has attracted worldwide attention. The South China Sea is the important center of coral reefs. Reef-fish is a crucial component in coral reef ecosystem. However, studies on the long-term variation in the biololgy of coral reef fish in the South China Sea are very lacking. To enhance our understanding of variation in reef fish biology in the South China Sea, we investigated long-term changes in some biological indicators of three dominant coral reef fishes (Lutjanus kasmira, Gnathodentex aureolineatus, and Cephalopholis urodeta) at the Yongshu Reef of the South China Sea between 1998–1999 and 2016–2019, and examined the effects of fishing and sea surface temperature on their biology. Compared with 1998–1999, average body length, average body mass, large fish indicator, feeding level and relative fatness of Lutjanus kasmira and Gnathodentex aureolineatus decreased in 2016–2019, but Cephalopholis urodeta did not. The relative fatness was positively correlated with the feeding level, which indicated that the decline of feeding level decreased the relative fatness. Fishing had the most important negative impact on biological changes. In the past two decades, Lutjanus kasmira had the most obvious decline in size and relative fatness, followed by Gnathodentex aureolineatus, but Cephalopholis urodeta had almost no decline. We hypothesized that different coral reef fishes have different abilities to maintain population stability under external pressures, and the differences in vulnerability of three fish species were the main reasons for their different responses to external pressures. To promote the conservation of coral reef fish, we recommend taking rigorous management to protect habitat.

Owing to climate change and anthropogenic stressors, the abundance and diversity of reef fishes have globally decreased. However, we know little about the long-term change in reef fishes in the South China Sea (SCS). To reveal the response of reef fishes to these threats in the SCS, based on the fish specimens at Yongshu Reef lagoon collected in 1999 and 2016–2019, this study investigated variations in fish composition and community structure. Additionally, we inferred the changes in the coral cover of Yongshu Reef based on the change of the coral cover of near Meiji Reef in the SCS, sea surface temperature (SST) in Yongshu Reef, and total annual catch of Epinephelinae from China in the SCS. We found that compared with 1999, the number of dominant species in 2016–2019 decreased. The relative dominance of the first dominant species increased from 24.46 in 1999 to 39.44 in 2016–2019. Indices of catch per unit effort, species diversity and richness declined from 1999 to 2016–2019. Community pattern changed with some species with a higher trophic level (3.7–4.5) decreased, while those with lower trophic level (2.2–4.1) increased greatly. Some species with high economic value and important ecological functions decreased or disappeared locally. Correlation analysis indicated that declining coral cover, increasing fishing and rising SST were clearly associated with changes in fish community structure at Yongshu Reef. We speculated that declining coral cover and increasing fishing had a direct impact on the degradation of fish communities at Yongshu Reef lagoon, but increasing SST had an indirect impact on that. To conserve coral reef fish, it is recommended to take rigorous measures for improving habitat and protecting resource.

Abstract Background Tandem mass spectrometry (MS MS) and simple fluorometric assays are currently used in newborn screening programs to detect inborn errors of metabolism (IEM). The aim of the study was to evaluate the clinical utility of exome sequencing as a second tier screening method to assist clinical diagnosis of the newborn. Methods A novel PCR-exome amplification and re-sequencing (PEARS) assay was designed and used to detect mutations in 122 genes associated with 101 IEM. Newborn bloodspots positive by biochemical testing were analysed by PEARS assay to detect pathogenic mutations relevant to the IEM. Results In initial validation studies of genomic DNA samples, PEARS assay correctly detected 25 known mutations associated with 17 different IEM. Retrospective gene analysis of newborns with clinical phenylketonuria (PKU), identified compound heterozygote phenylalanine hydroxylase (PAH) gene mutations in eight of nine samples (89%). Prospective analysis of 211 bloodspots correctly identified the two true PKU samples, yielding positive and negative predictive values of 100%. Testing of 8 true positive MS MS samples correctly identified potentially pathogenic compound heterozygote genotypes in 2 cases of citrullinemia type 1 and one case each of methylmalonic acidemia, isobutyryl-CoA dehydrogenase deficiency, short chain acyl-CoA dehydrogenase deficiency and glutaric acid type II and heterozygous genotypes in 2 cases of autosomal dominant methioninemia. Analysis of 11 of 12 false positive MS MS samples for other IEM identified heterozygous carriers in 8 cases for the relevant genes associated with the suspected IEM. In the remaining 3 cases, the test revealed compound heterozygote mutations in other metabolic genes not associated with the suspected IEM, indicating a misinterpretation of the original MS MS data. Conclusions The PEARS assay has clinical utility as a rapid and cost effective second-tier test to assist the clinician to accurately diagnose newborns with a suspected IEM.