Seasonal variations and sources of atmospheric EPFRs in a megacity in severe cold region: Implications for the influence of strong coal and biomass combustion.

Environmentally persistent free radicals (EPFRs) can pose exposure risks by inducing the generation of reactive oxygen species. As a new class of pollutants, EPFRs have been frequently detected in atmospheric particulate matters. In this study, the seasonal variations and sources of EPFRs in a severe cold region in Northeastern China were comprehensively investigated, especially for the high pollution events. The geomean concentration of EPFRs in the total suspended particle was 6.58 × 1013 spins/m3 and the mean level in winter was one order of magnitude higher than summer and autumn. The correlation network analysis showed that EPFRs had significantly positive correlation with carbon component, K+ and PAHs, indicating that EPFRs were primarily emitted from combustion and pyrolysis process. The source appointment by the Positive Matrix Factorization (PMF) model indicated that the dominant sources in the heating season were coal combustion (48.4%), vehicle emission (23.1%) and biomass burning (19.4%), while the top three sources in the non-heating season were others (41.4%), coal combustion (23.7%) and vehicle emissions (21.2%). It was found that the high EPFRs in cold season can be ascribed to the extensive use of fossil fuel for heating demand; while the high EPFRs occurred in early spring were caused by the large-scale opening combustion of biomass. In summary, this study provided important basic information for better understanding the pollution characteristics of EPFRs, which suggested that the implementation of energy transformation and straw utilization was benefit for the control of EPFRs in severe cold region.

Platelet membrane-derived microparticles may be biomarkers in patients with hepatocellular carcinoma and can promote the invasion and metastasis of hepatoma carcinoma cells.

BACKGROUND: Platelet membrane-derived microparticles (PMPs) released by apheresis platelets (APs) during storage are involved in immunomodulatory and tumor processes. However, few studies have emphasized the relationship between PMPs and hepatocellular carcinoma (HCC). METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to detect PMPs in the plasma of HCC patients and healthy individuals. ELISA and flow cytometry were separately applied to analyze the variation in PMPs from APs prepared after 0, 3, 5, and 7 days of storage. Transwell was used to demonstrate the effects of PMPs on the invasion and migration of HCC cells. HCC-related indicators and invasion and migration-related markers were detected in vivo. RESULTS: We found the amount of PMPs was significantly increased in HCC patients. There was also a significant difference in the amount of PMPs in APs with prolonged storage time. Further, the PMPs in D5 promoted the invasion and migration of HepG2 and Huh7 cells. Transcriptomics revealed striking differences in the expression of many tumor metastasis associated genes with PMPs treatment. PMPs promoted tumor growth and weight loss in HCC-bearing mice, and Western blot results showed that invasion and migration-related indicators also increase. CONCLUSION: The content of PMPs in the plasma of HCC patients increases, and it can also promote the invasion and migration of HCC.

Health Risk Assessment of Organophosphate Flame Retardants in Soil Across China Based on Monte Carlo Simulation.

Health risks from exposure to contaminants are generally estimated by evaluating concentrations of the contaminants in environmental matrixes. However, accurate health risk assessment is difficult because of uncertainties regarding exposures. This study aims to utilize data on the concentrations of organophosphate flame retardants (OPFRs) in surface soil across China coupled with Monte Carlo simulations to compensate for uncertainties in exposure to evaluate the health risks associated with contamination of soil with this class of flame retardants. Results revealed that concentrations of ∑OPFRs were 0.793-406 ng/g dry weight (dw) with an average of 23.2 ng/g dw. In terms of spatial distribution, higher OPFRs concentrations were found in economically developed regions. Although the values of health risk of OPFRs in soil across China were below the threshold, the high concentrations of OPFRs in soil in some regions should attract more attentions in future. Sensitivity analysis revealed that concentrations of OPFRs in soil, skin adherence factor, and exposure duration were the most sensitive parameters in health risk assessment. In summary, the study indicated that the national scale soil measurement could provide unique information on OPFRs exposure and health risk assessment, which was useful for the management of soil in China and for better understanding of the environmental fate of OPFRs in the global perspective.

Comparative transcriptome analysis reveals immunoregulation mechanism of lncRNA-mRNA in gill and skin of large yellow croaker (Larimichthys crocea) in response to Cryptocaryon irritans infection.

BACKGROUND: Cryptocaryonosis caused by Cryptocaryon irritans is one of the major diseases of large yellow croaker (Larimichthys crocea), which lead to massive economic losses annually to the aquaculture industry of L. crocea. Although there have been some studies on the pathogenesis for cryptocaryonosis, little is known about the innate defense mechanism of different immune organs of large yellow croaker. RESULTS: In order to analyze the roles of long non-coding RNAs and genes specifically expressed between immune organs during the infection of C. irritans, in this study, by comparing transcriptome data from different tissues of L. crocea, we identified tissue-specific transcripts in the gills and skin, including 507 DE lncRNAs and 1592 DEGs identified in the gills, and 110 DE lncRNAs and 1160 DEGs identified in the skin. Furthermore, we constructed transcriptome co-expression profiles of L. crocea gill and skin, including 7,503 long noncoding RNAs (lncRNAs) and 23,172 protein-coding genes. Gene Ontology (GO) annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the DEGs and the target genes of the DE lncRNAs in the gill were specifically enriched in several pathways related to immune such as HIF-1 signaling pathway. The target genes of DE lncRNAs and DEGs in the skin are specifically enriched in the complement and coagulation cascade pathways. Protein-protein interaction (PPI) network analysis identified 3 hub genes including NFKBIA, TNFAIP3 and CEBPB, and 5 important DE lncRNAs including MSTRG.24134.4, MSTRG.3038.5, MSTRG.27019.3, MSTRG.26559.1, and MSTRG.10983.1. The expression patterns of 6 randomly selected differentially expressed immune-related genes were validated using the quantitative real-time PCR method. CONCLUSIONS: In short, our study is helpful to explore the potential interplay between lncRNAs and protein coding genes in different tissues of L. crocea post C. irritans and the molecular mechanism of pathogenesis for cryptocaryonosis. HIGHLIGHTS: Skin and gills are important sources of pro-inflammatory molecules, and their gene expression patterns are tissue-specific after C. irritans infection. 15 DEGs and 5 DE lncRNAs were identified as hub regulatory elements after C. irritans infection The HIF-1 signaling pathway and the complement and coagulation cascade pathway may be key tissue-specific regulatory pathways in gills and skin, respectively.

Steady-State Based Model of Airborne Particle/Gas and Settled Dust/Gas Partitioning for Semivolatile Organic Compounds in the Indoor Environment.

Indoor semivolatile organic compounds (SVOCs), present in the air, airborne particles, settled dust, and other indoor surfaces, can enter the human body through several pathways. Knowing the partitioning between gaseous and particulate phases is important in identifying specific pathway contributions and thereby accurately assessing human exposure. Numerous studies have developed equilibrium equations to predict airborne particle/gas (P/G) partitioning in air (KP) and dust/gas (D/G) partitioning in settled dust (KD). The assumption that P/G and D/G equilibria are instantaneous for airborne and settled dust phases, commonly adopted by current indoor fate models, is not likely valid for compounds with high octanol-air partition coefficients (KOA). Here, we develop steady-state based equations to predict KP and KD in the indoor environment. Results show that these equations perform well and are verified by worldwide monitoring data. It is suggested that instantaneous steady state could work for P/G and D/G partitioning of SVOCs in indoor environments, and the equilibrium is just a special case of the steady state when log KOA < 11.38 for P/G partitioning and log KOA < 10.38 for D/G partitioning. These newly developed equations and methods provide a tool for more accurate assessment for human exposure to SVOCs in the indoor environment.

Platelet supernatant with longer storage inhibits tumor cell growth.

BACKGROUND: Platelet transfusion is an essential supportive treatment for cancer patients. Platelets promote metastasis, but their role in tumor growth remains controversial. This study aimed to explore the impact of apheresis platelet supernatants of different storage periods on tumor cell growth, optimize blood transfusion timing, and provide a reference for reducing the risks of platelet transfusion in cancer patients. METHODS: Eight human tumor cell lines, including HepG2, HuH7, SMMC-7721, HeLa, HCT116, MCF-7, K562, and Jurkat were cultured. After culturing the platelet supernatant of days 0, 3, 5, and 7 with tumor cells, counting kit 8 (CCK-8), scratch assay, and propidium iodide (PI) were used to evaluate cell proliferation, migration, and cell cycle, respectively. Metabolomics analysis was performed to confirm whether differential metabolites produced during platelet storage are involved in the cancer pathway. RESULTS: Platelet supernatants inhibit tumor cell proliferation by blocking the cell cycle at the G0/G1 phase, and their inhibitory effect increases with storage time. However, platelets promote tumor cells to form cytoskeletal connections, thereby promoting migration. Besides, metabonomics analysis of platelet supernatants during different storage periods reveals that upregulated differential metabolites are involved in cancer-related pathways. CONCLUSION: The role of platelets in tumor cells is two-sided, that is, they inhibit proliferation while promoting migration. Therefore, additional in-depth studies on the appropriate timing of platelet transfusion are necessary.

Identification of genes related to low-grade glioma progression and prognosis based on integrated transcriptome analysis.

Glioma is one of the most common types of human brain tumor, with high mortality in high-grade gliomas (HGG). Low-grade gliomas (LGG) can progress into HGG, leading to poor prognosis. However, it is unclear what factors affect the progression of LGG to HGG. This study aims to explore the function of the crosstalk genes on the progression and prognosis of LGG using bioinformatics analysis. Integrated transcriptome analysis was used to screen differentially expressed genes (DEGs). Then, gene ontology (GO) function enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to investigate the association between DEGs and gene functions and pathways by ClusterProfiler package and ClueGO plug-in. Protein-protein interaction (PPI) network analysis was applied to explore the connection between genes and biological processes. Subsequently, the gene clusters were analyzed using the Centiscape and molecular complex detection (MCODE) plug-in in Cytoscape software, where the crosstalk genes were identified for further study. Ultimately, the UALCAN website and Gene Expression Profiling Interactive Analysis (GEPIA) website were performed to visualize the expression levels and survival curves of genes, respectively. There were 74 DEGs identified in glioma, including 55 upregulated genes and 19 downregulated genes, which mainly were enriched in extracellular matrix (ECM)-receptor interaction, focal adhesion, PI3K-Akt signaling pathway, and so on. Then, six crosstalk genes were selected, including COL1A1, COL1A2, COL3A1, COL4A1, COL4A2, and COL5A2 genes. Overall survival (OS) analysis of crosstalk genes was conducted on the GEPIA website. High expression levels of crosstalk genes were closely related to the low survival rate of patients with LGG. The overexpressed crosstalk genes, such as COL1A1, COL1A2, COL3A1, COL4A1, COL4A2, and COL5A2 may participate in the progression and poor prognosis of LGG through the ECM-receptor interaction pathway.

Genome-wide identification, evolution, and mRNA expression of complement genes in common carp (Cyprinus carpio).

Complement is a complex component of innate immune system, playing an important role in defense against pathogens and host homeostasis. The complement system has been comprehensively studied in mammals, however less is known about complement in teleost, especially in tetraploid common carp (Cyprinus carpio). In this study, a total of 110 complement genes were identified and characterized in common carp, which include almost all the homologs of mammalian complement genes. These genes were classified into three pathways (alternative pathways, lectin pathways and classical pathways), similar to those in mammals. Phylogenetic and selection pressure analysis showed that the complement genes were evolving-constrained and the function was conserved. Most of the complement genes were highly expressed in spleen, liver, brain and skin among the tested 12 health tissues of common carp. After Aeromonas hydrophila infection in the common carp, many members of complement genes were activated to bring about an immune response and expressed to against any pathogenic encroachment. Gene expression divergences which were found between two homoeologous genes suggested the functional divergences of the homoeologous genes after the 4R WGD event, revealing the evolutionary fate of the tetraploid common carp after the recent WGD.

Transcriptome analysis reveals the temporal gene expression patterns in skin of large yellow croaker (Larimichthys crocea) in response to Cryptocaryon irritans infection.

Large yellow croaker (Larimichthys crocea) is one of the most important mariculture fish in China. In the past decades, cryptocaryonosis caused by Cryptocryon irritans has led to huge economic losses, posing great threat to the healthy and sustainable development of L. crocea mariculture industry. As the largest immunologically active mucosal organ in fish, skin provides the first defense line against external pathogens. To better understand the gene expression dynamics, the large yellow croakers were artificially infected with C. irritans and their skin tissues were collected at 0 h, 24 h, 48 h, 72 h and 96 h post infection. The total RNA in the skin tissues were extracted and the transcriptome were sequenced. After sequencing, a total of 1,131, 311, 140 million high quality RNA-seq reads were collected. A set of 215, 473, 968, 1055 differentially expressed genes were identified at 24 h, 48 h, 72 h and 96 h post infection respectively. Further analysis clustered these DEGs into six profiles and 75 hub genes for six profiles were identified. Among these hub genes, 18 immune related genes including TLR5, TOPK, NFKBIZ, MAPK14A were identified post C. irritans infection. Cytokine-cytokine receptor interaction was the only pathway that significantly enriched at four timepoints post infection. This study provides an in-depth understanding of skin transcriptome variance of large yellow croaker after C. irritans infection, which would be helpful for further understanding of the molecular mechanism of L. crocea in response to C. irritans infection.

Transcriptional differences provide insight into environmental acclimatization in wild amur ide (Leuciscus waleckii) during spawning migration from alkalized lake to freshwater river.

Amur ide (Leuciscus waleckii) inhabits alkaline water in Lake Dali Nur and migrates to fresh water river for spawning every year. To investigate the potential genetic mechanisms underlying their alkaline acclimation, adaptation, and spawning migration, we performed differential gene expression analysis using high-throughput RNA-Seq data from liver of Amur ide samples collected before and after spawning migration. First, the short RNA-Seq reads were de novo assembled into 44,318 contigs, and provided the transcriptome reference sequences. Differential gene expression analysis identified 2575 genes with significant differential expression (p-value ≤.01, log2-fold-change ≥2). GO enrichment and KEGG pathway analyses were subsequently performed to determine gene functions and regulation. The results indicated that there were numerous differentially expressed genes involved in acid-base regulation, nitrogenous waste excretion, sexual maturation and reproduction, and stress response. These results provide fundamental information for further analyses of the physiological and molecular mechanisms underlying Amur ide alkaline acclimation, adaptation, and spawning migration.

Molecular cloning of two molluscan caspases and gene functional analysis during Crassostrea angulata (Fujian oyster) larval metamorphosis.

Caspases have been demonstrated to possess important functions in apoptosis and immune system in vertebrate. But there is less information reported on the oyster larval development. In the present work, two full-length molluscan caspase genes, named Cacaspase-2 and Cacaspase-3, were characterized for the first time from Fujian oyster, Crassostrea angulata. Which respectively encode two predicted proteins both containing two caspase domains of p20 and p10 including the cysteine active site pentapeptide "QACRG" and the histidine active site signature. Otherwise Cacaspase-2 also contains a caspase recruitment domain. Homology and phylogenetic analysis showed that Cacaspase-2 shared high similarity with initiator caspase-2 groups, but Cacaspase-3 clustered together with executioner caspase-3 groups. Cacaspase-2 and Cacaspase-3 mRNA were both highly expressed in gills and labial palp and were significantly expressed highly in larvae during settlement and metamorphosis. Through the whole mount in situ hybridization, the location of Cacaspase-2 is in the foot of the oyster larvae and the location of Cacaspase-3 is in both the foot and velum tissues. These results implied that Cacaspase-2 and Cacaspase-3 genes play a key role in the loss of foot and Cacaspase-3 gene has an important function in the loss of velum during larvae metamorphosis in C. angulata.

Open-source genomic analysis of Shiga-toxin-producing E. coli O104:H4.

An outbreak caused by Shiga-toxin­producing Escherichia coli O104:H4 occurred in Germany in May and June of 2011, with more than 3000 persons infected. Here, we report a cluster of cases associated with a single family and describe an open-source genomic analysis of an isolate from one member of the family. This analysis involved the use of rapid, bench-top DNA sequencing technology, open-source data release, and prompt crowd-sourced analyses. In less than a week, these studies revealed that the outbreak strain belonged to an enteroaggregative E. coli lineage that had acquired genes for Shiga toxin 2 and for antibiotic resistance.

Effect of microRNA-101 on proliferation and apoptosis of human osteosarcoma cells by targeting mTOR.

Studies have proved that microRNA-101 (miR-101) functions as a tumor suppressor and is associated with growth and apoptosis of various human cancers. However, the role of miR-101 in osteosarcoma and the possible mechanism by which miR-101 affects the tumor growth and apoptosis have not been fully elucidated. In this study, we found that the expression of miR-101 was down-regulated in osteosarcoma tissues and Saos-2 cell line as compared with that in adjacent non-neoplastic bone tissues and the osteoblastic cell line. To better characterize the role of miR-101 in osteosarcoma, we used a gain-of-function analysis by transfecting human osteosarcoma cell line Saos-2 with chemically synthesized miR-101 mimics. The results showed that overexpression of miR-101 inhibited the proliferation and promoted the apoptosis of Saos-2 cells. Meanwhile, bioinformatic analysis demonstrated that mTOR gene was a direct target of miR-101. Overexpression of miR-101 significantly decreased the expression of mTOR at both mRNA and protein levels in Saos-2 cells, consequently inhibiting Saos-2 cells proliferation and promoting cells apoptosis in an mTOR-dependent manner. Taken together, these data suggest that miR-101 may act as a tumor suppressor, which is commonly downregulated in both osteosarcoma tissues and cells. mTOR plays an important role in mediating miR-101 dependent biological functions in osteosarcoma. Reintroduction of miR-101 may be a novel therapeutic strategy by down-regulating mTOR expression.

Molecular characterization, expression pattern and immunologic function of CD82a in large yellow croaker (Larimichthys crocea).

Visceral white spot disease (VWND) caused by Pseudomonas plecoglossicida poses a major threat to the sustainable development of large yellow croaker (Larimichthys crocea) aquaculture. Genome-wide association analysis (GWAS) and RNA-seq research indicated that LcCD82a play an important role in resistance to visceral white spot disease in L. crocea, but the molecular mechanism of LcCD82a response to P. plecoglossicida infection is still unclear. In this study, we cloned and validated the Open Reading Frame (ORF) sequence of LcCD82a and explored the expression profile of LcCD82a in various tissues of L.crocea. In addition, two different transcript variants (LcCD82a-L and LcCD82a-S) of LcCD82a were identified that exhibit alternative splicing patterns after P. plecoglossicida infection, which may be closely related to the immune regulation during pathogenetic process of VWND. In order to explore the function of LcCD82a, we purified the recombinant protein of LcCD82a-L and LcCD82a-S. The bacterial agglutination and apoptosis function analysis showed that LcCD82a may involve in extracellular bacterial recognition, agglutination, and at the same time participate in the process of antigen presentation and induction of cell apoptosis. Collectively, our studies demonstrate that LcCD82a plays a crucial role in regulating apoptosis and antimicrobial immunity.

Chromosome-level assembly and gene annotation of Decapterus maruadsi genome using Nanopore and Hi-C technologies.

Decapterus maruadsi is one of the representative offshore fish in the Western Pacific. Since the last century, it has become a commercially valuable marine fishery species in the Western Pacific region. Despite its high economic value, there is still a lack of high-quality reference genome of D. maruadsi in germplasm resource evaluation research. Here we report a chromosome-level reference genome of D. maruadsi based on Nanopore sequencing and Hi-C technologies. The whole genome was assembled through 169 contigs with a total length of 723.69 Mb and a contig N50 length of 24.67 Mb. By chromosome scaffolding, 23 chromosomes with a total length of 713.58 Mb were constructed. In addition, a total of 199.49 Mb repetitive elements, 33,515 protein-coding genes, and 6,431 ncRNAs were annotated in the reference genome. This reference genome of D. maruadsi will provide a solid theoretical basis not only for the subsequent development of genomic resources of D. maruadsi but also for the formulation of policies related to the protection of D. maruadsi.

Temperature dependence of the rain-gas and snow-gas partition coefficients for nearly a thousand chemicals.

Compared to the particle-gas partition coefficients (KPG), the rain-gas (KRG) and snow-gas (KSG) partition coefficients are also essential in studying the environmental behavior and fate of chemicals in the atmosphere. While the temperature dependence for the KPG have been extensively studied, the study for KRG and KSG are still lacking. Adsorption coefficients between water surface-air (KIA) and snow surface-air (KJA), as well as partition coefficients between water-air (KWA) and octanol-air (KOA) are vital in calculating KRG and KSG. These four basic adsorption and partition coefficients are also temperature-dependent, given by the well-known two-parameters Antoine equation logKXY = AXY + BXY/T, where KXY is the adsorption or partition coefficients, AXY and BXY are Antoine parameters (XY stand for IA, JA, WA, and OA), and T is the temperature in Kelvin. In this study, the parameters AXY and BXY are calculated for 943 chemicals, and logKXY can be estimated at any ambient temperature for these chemicals using these Antoine parameters. The results are evaluated by comparing these data with published experimental and modeled data, and the results show reasonable accuracy. Based on these coefficients, temperature-dependence of logKRG and logKSG is studied. It is found that both logKRG and logKSG are linearly related to 1/T, and Antoine parameters for logKRG and logKSG are also estimated. Distributions of the 943 chemicals in the atmospheric phases (gas, particle, and rain/snow), are illustrated in a Chemical Space Map. The findings reveal that, at environmental temperatures and precipitation days, the dominant state for the majority of chemicals is the gaseous phase. All the AXY and BXY values for logKSG, logKRG, and basic adsorption and partition coefficients, both modeled by this study and collected from published work, are systematically organized into an accessible dataset for public utilization.

Chromosome-level haplotype-resolved genome assembly for Takifugu ocellatus using PacBio and Hi-C technologies.

Takifugu species serve as a model system for evolutionary studies due to their compact genomes and diverse phenotypes. The ocellated puffer (Takifugu ocellatus), characterized by special colouration, is a scarce anadromous species in the genus Takifugu. As an ornamental and tasty fish species, T. ocellatus has moderate economic value. However, the available genomic resources for this pufferfish are still limited. Here, a chromosome-level reference genome, as well as two haploid genomes, was constructed by PacBio HiFi long sequencing and Hi-C technologies. The total length of the reference genome was 375.62 Mb with a contig N50 of 11.55 Mb. The assembled sequences were anchored to 22 chromosomes with an integration efficiency of 93.78%. Furthermore, 28,808 protein-coding genes were predicted. The haplotype-resolved reference genome of T. ocellatus provides a crucial resource for investigating the explosive speciation of the Takifugu genus, such as elucidating evolutionary histories, determining the genetic basis of trait evolution, and supporting future conservation efforts.

Comparative genomics analysis and genome assembly integration with the recombination landscape contribute to Takifugu bimaculatus assembly refinement.

Takifugu genus has been brought to the fore in scientific and practical research due to its compact genome, explosive speciation progress and economic value. Here we updated the chromosome-level genome of Takifugu bimaculatus by an ultra-high-density linkage map, a classic and accurate way of chromosome assembly. The map constituted a robust assembly frame, with 92.2% (372.77 Mb) of the draft genome cumulatively placed. With intraspecies and interspecies comparative genomic analysis, we developed a criterion to quantify the differences between assemblies and established a novel way to integrate information from multiple assemblies. The integrated assembly rectified potential mis-assemblies, greatly improving the genome contiguity and correctness. Our results rendered profound information on the genetic recombination of T. bimaculatus and provided new insights into effective genome assembly. The consolidated assembly will be a contributory tool of T. bimaculatus and broadly across the Takifugu by providing a convincing reference for genomic research.

The adaptive evolution of Leuciscus waleckii in Lake Dali Nur and convergent evolution of Cypriniformes fishes inhabiting extremely alkaline environments.

Leuciscus waleckii is widely distributed in Northeast Asia and has high economic value. The population in Lake Dali Nur can adapt to extremely alkaline-saline water with bicarbonate over 50 mmol/L (pH 9.6), thus providing an exceptional model for exploring the mechanisms of adaptive evolution under extreme alkaline environments. Here, we assembled a high-quality chromosome-level reference genome for L. waleckii from Lake Dali Nur. Based on the resequencing of 85 individuals from divergent populations, the historical population size of L.waleckii in Lake Dali Nur dramatically expanded in a thousand years approximately 13,000 years ago, and experienced a cliff recession in the process of adapting to the alkaline environment of Lake Dali Nur approximately 6,000 years ago. Genome scans between freshwater and alkaline populations further revealed the significant selective sweep regions from Lake Dali Nur, which harbour a set of candidate genes involved in hypoxia tolerance, ion transport, acid-base regulation and nitrogen metabolism. 5 alkali population-specific nonsynonymous mutations were identified in CA15 gene copies. In addition, two sites with convergent amino acid mutation were detected in the RHCG-a gene among several alkali environment adapted Cypriniformes fish. Our findings provide comprehensive insight into the genomic mechanisms of L. waleckii and reveal their adaptative evolution under extreme alkaline environments.