RESUMEN
Huperzia crispata is a traditional Chinese herb plant and has attracted special attention in recent years for its products Hup A can serve as an acetylcholinesterase inhibitor (AChEI). Although the chloroplast (cp) genome of H. crispata has been studied, there are no reports regarding the Huperzia mitochondrial (mt) genome since the previously reported H. squarrosa has been revised as Phlegmariurus squarrosus. The mt genome of H. crispata was sequenced using a combination of long-read nanopore and Illumina sequencing platforms. The entire H. crispata mt genome was assembled in a circular with a length of 412,594 bp and a total of 91 genes, including 45 tRNAs, 6 rRNAs, 37 protein-coding genes (PCGs), and 3 pseudogenes. Notably, the rps8 gene was present in P. squarrosus and a pseudogene rps8 was presented in H. crispata, which was lacking in most of Pteridophyta and Gymnospermae. Intron-encoded maturase (mat-atp9i85 and mat-cobi787) genes were present in H. crispata and P. squarrosus, but lost in other examined lycophytes, ferns, and Gymnospermae plants. Collinearity analysis showed that the mt genome of H. crispata and P. squarrossus is highly conservative compared to other ferns. Relative synonymous codon usage (RSCU) analysis showed that the amino acids most frequently found were phenylalanine (Phe) (4.77%), isoleucine (Ile) (4.71%), lysine (Lys) (4.26%), while arginine (Arg) (0.32%), and histidine (His) (0.42%) were rarely found. Simple sequence repeats (SSR) analysis revealed that a total of 114 SSRs were identified in the mt genome of H. crispata and account for 0.35% of the whole mt genome. Monomer repeats were the majority types of SSRs and represent 91.89% of the total SSRs. In addition, a total of 1948 interspersed repeats (158 forward, 147 palindromic, and 5 reverse repeats) with a length ranging from 30 bp to 14,945 bp were identified in the H. crispata mt genome and the 30-39-bp repeats were the most abundant type. Gene transfer analysis indicated that a total of 12 homologous fragments were discovered between the cp and mt genomes of H. crispata, accounting for 0.93% and 2.48% of the total cp and mt genomes, respectively. The phylogenetic trees revealed that H. crispata was the sister of P. squarrosus. The Ka/Ks analysis results suggested that most PCGs, except atp6 gene, were subject to purification selection during evolution. Our study provides extensive information on the features of the H. crispata mt genome and will help unravel evolutionary relationships, and molecular identification within lycophytes.
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Genoma Mitocondrial , Huperzia , Plantas Medicinales , Plantas Medicinales/genética , Huperzia/genética , Filogenia , AcetilcolinesterasaRESUMEN
BACKGROUND: Huperzia crispata, belonging to the Huperziaceae family, is one of the most essential resources of huperzine A for candidate drugs to treat Alzheimer's diseases. However, there is very limited information about H. crispat, and its taxonomic status and interspecific relationships between Huperzia species are still unclear. To investigate the taxonomic classification of Huperzia species and identify species discrimination markers, the complete chloroplast (cp) genome of H. crispata was sequenced and characterized for the first time. METHODS AND RESULTS: Total genomic DNA was isolated and sequenced using the next-generation Illumina NovaSeq 6000 platform. The data were filtered, assembled and annotated by a series software and web service. The results were as follows: the cp genome of H. crispata was 154,320 bp long with a large single-copy (LSC) region of 104,023 bp, a small single-copy (SSC) region of 19,671 bp, and a pair of inverted repeat (IRa and IRb) regions of 15,313 bp. A total of 131 genes, including 87 protein-coding genes, 36 transfer RNA genes (tRNAs), and eight ribosome RNA genes (rRNAs), were annotated in the cp genome. The contraction and expansion of the inverted repeat (IR) regions were relatively conserved in the Huperzia genus. Codon usage bias analysis showed that the encoding rate at the 3-end of codon A/T (74.34%) was significantly higher than that of C/G (25.66%). A total of 8 hotspot loci with high Pi values (> 0.06) were identified in the four Huperzia species based on nucleic acid diversity analysis. Ka/Ks selective pressure analysis demonstrated that the cemA gene is the most common gene undergoing positive selection among Huperzia. In addition, a total of 261 simple sequence repeats and 179 interspersed repeats were identified in the cp genome. Phylogenetic tree analysis based on the complete protein sequences of 23 related species of H. crispata indicated that H. serrata f. longipetiolata is a sister of H. crispata, suggesting that H. serrata f. longipetiolata and H. crispata are more closely related than H. serrata and H. lucidula. CONCLUSIONS: The results strongly supported that H. crispata was more closely related to H. serrata f. longipetiolata than to H. serrata and H. lucidula within the Huperzia genus. The outcome provided important information for the phylogenetic analysis of the subsequent specific molecular species identification in Huperzia. The present results will provide valuable information for further research into the classification, phylogeny and species identification of Huperzia plants.
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Genoma del Cloroplasto , Huperzia , Genoma del Cloroplasto/genética , Filogenia , Huperzia/genética , Repeticiones de Microsatélite/genética , Codón , ARN de Transferencia/genéticaRESUMEN
BACKGROUND: Huperzine A (Hup A) has attracted considerable attention as an effective therapeutic candidate drug used to treat Alzheimer's disease. Whereas, the production of Hup A from wild plants faced a major challenge, which is the wild Huperzia Serrata harbor a low Hup A content, has a long-life cycle, and has a small yield. At present, several reports showed that Hup A is produced by various endophytic fungal strains isolated from H. serrata, thereby providing an alternative method to produce the compound and reduce the consumption of this rare and endangered plant. However, till now, very few comprehensive studies are available on the biological diversity and structural composition of endophytic fungi and the effects of endophytic fungi on the Hup A accumulation in H. serrata. RESULTS: In this research, the composition and diversity of fungal communities in H. serrata were deciphered based on high-throughput sequencing technology of fungal internal transcribed spacer regions2 (ITS2). The correlation between endophytic fungal community and Hup A content was also investigated. Results revealed that the richness and the diversity of endophytic fungi in H. serrata was various according to different tissues and different ecological areas. The endophytic fungal communities of H. serrata exhibit species-specific, ecological-specific, and tissue-specific characteristics. There are 6 genera (Ascomycota_unclassified, Cyphellophora, Fungi_unclassified, Sporobolomyces, and Trichomeriaceae_unclassified) were significantly positively correlated with Hup A content in all two areas, whereas, there are 6 genera (Auricularia, Cladophialophora, Cryptococcus, Mortierella, and Mycena) were significantly negatively correlated with Hup A content of in all two areas. CONCLUSIONS: This study indicated a different composition and diverse endophytic fungal communities in H. serrata from different organs and ecological areas. The current study will provide the realistic basis and theoretical significance for understanding the biological diversity and structural composition of endophytic fungal communities in H. serrata, as well as providing novel insights into the interaction between endophytic fungi and Hup A content.
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Ascomicetos , Basidiomycota , Huperzia , Micobioma , Alcaloides , Biodiversidad , Endófitos , Hongos , Huperzia/microbiología , SesquiterpenosRESUMEN
Health risk analysis can predict and control the risks posed by heavy metals, especially in drinking water, which is a highly sensitive environmental receptors. In order to evaluate heavy metal pollution in drinking water, the monthly average concentrations of As, Cd, Cu, Hg, Ni, and Zn were used to assess the health risk between January 2015 and December 2018 in a drinking water source. Furthermore, Spearman rank correlation coefficient and the ARIMA model were used to analyze temporal variations. The results showed that the monthly average concentrations of heavy metals exceeded the class â ¢ values as specified by Chinese environmental quality standard for surface water(GB 3838-2002), especially Hg with a minimum monthly average four times more than that set by the standard limits. Overall, the order of carcinogenic risk of As and Cd was decreased; the non-carcinogenic risk of Zn, Cu, Ni, Pb, and Hg was increased. Further, the comprehensive non-carcinogenic risk for adults was lower than 1 throughout the study period except February 2015, when the comprehensive non-carcinogenic risk for children was lower than or close to 1 after October 2017, and the comprehensive carcinogenic risk for children was more than 10-4. Meanwhile, the children's health risks are higher than that for adults, with the main health risk characteristic factors of As, Cd, and Hg. The Spearman rank correlation coefficient were -0.714069, -0.773122, and -0.62234, indicating the significant downward trend from 2015 to 2018. However, the children's comprehensive carcinogenic risk, whose average value was 0.000234 much more than 10-4, had significant upward trend in 2018 with Spearman rank correlation coefficient 0.902098. The ARIMA(3,1,3) model was able to predict the comprehensive carcinogenic risk for children from heavy metals in drinking water, and the result indicated the children comprehensive carcinogenic risk should be monitored to ensure levels between 0.000200 and 0.000302. The study has positive significance for risk warning and environmental management compared to the analysis and prediction of health risk from heavy metals in drinking water sources based on time series models.
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Agua Potable , Metales Pesados , Contaminantes Químicos del Agua , Adulto , Niño , China , Agua Potable/análisis , Monitoreo del Ambiente , Humanos , Metales Pesados/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/efectos adversos , Contaminantes Químicos del Agua/análisisRESUMEN
Spatial characteristics analysis of the human health risk posed by heavy metals in cultivated soils is of great significance, with the potential to prevent and control soil pollution, protect human health, provide a basis for risk management, etc. In this paper, a methodological system, including a USEPA health risk assessment model, differentiation and factor detector within a geographical detector, and optimized initial model of rank-size theory, was constructed from a geographical perspective. Taking a city in Jiangsu province as the research object, we obtained the spatial differentiation and relative level of human health risk of Cr, Pb, Hg, and Cd in cultivated land by using the methodological system constructed and SPSS and ArcGIS software. The average concentrations of heavy metals (mg·kg-1) in the research area were Cr (65.207 mg·kg-1), Pb (25.486 mg·kg-1), Cd (0.238 mg·kg-1), and Hg (0.045 mg·kg-1), which were lower than the risk control standards for soil contamination of agricultural land in China. The children's non-cancer risk of Cr and Pb and the cancer risk to children and adults of Cr were 2.914385, 1.337503, 4.312679×10-6, and 8.137130×10-6, respectively, all of which exceeded the maximum acceptable limit in the research. Meanwhile, the spatial differentiation (q) of heavy metal health risk was between 0.005523 and 0.204238, which indicated that the high health risk posed by heavy metals should be paid attention to. The health risk rankings (R) of the children's non-cancer risk of Cr and Pb and the cancer risk of Cr in subregions 1, 2, 3, and 4 approached or exceeded 1, and were higher than in subregions 5, 6, and 7, for which R was lower than 0.1. The R values indicated than the high health risk is concentrated in the research region. This research has great significance in measuring the health risk of heavy metals in cultivated soil at different scales, and in forming control strategies with local conditions.
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Metales Pesados/análisis , Contaminantes del Suelo/análisis , Adulto , Niño , China , Ciudades , Monitoreo del Ambiente , Humanos , Medición de Riesgo , SueloRESUMEN
Oxidized single-wall carbon nanohorns (oxSWNHs) have shown great potential in drug delivery. The purpose of this study was to design an effective targeted drug delivery system (DDS) based on oxSWNHs, which could carry high dose of drug to tumor sites and improve the therapeutic efficacy with less adverse effects. OxSWNHs incorporated the anticancer drug vincristine (VCR) via physical adsorption, then wrapped DSPE-PEG-IGF-IR monoclonal antibody (mAb) through an amide liker to obtain the drug delivery system, VCR@oxSWNHs-PEG-mAb. The in vitro release behavior study indicated that the DDS had good sustained release and the cumulative release of VCR was 80% at 144h. Compared with free VCR, the tumor targeting drug delivery efficiently enhanced the cytotoxicity in cultured MCF-7 cells in vitro, and afforded higher antitumor efficacy without obvious toxic effects to normal organs in tumor mice in vivo. In addition, the targeted DDS could reduce the toxicity of VCR to the living mice. This study demonstrated that VCR@oxSWNHs-PEG-mAb might be promising for high treatment efficacy with minimal side effects in future cancer therapy.