The complete mitogenome dataset of the Critically Endangered estuarine pipefish, Syngnathus watermeyeri.

The Critically Endangered South African estuarine pipefish, Syngnathus watermeyeri, is one of the rarest teleost fish on the planet. In this analysed dataset, the complete mitochondrial genome of this species was assembled, annotated, and described. In addition, its evolutionary history was reconstructed in a Maximum Likelihood and a Bayesian framework. A circular mitochondrial contig 16 449 bp in length was assembled. A total of 13 protein-coding genes, 22 tRNAs and two rRNAs were annotated. The mitochondrial phylogenetic analysis showed that S. watermeyeri diverged from its widely distributed southern African sister species S. temminckii approximately 1.5 million years ago, and the ancestor of these two southern Afican pipefish species diverged from a clade of northern hemisphere pipefishes comprising S. acus, S. rostellatus, and S. typhle approximately 5.3 million years ago. The dataset presented here serves as the first step in understanding the evolutionary history of Africa's rarest pipefish.

New Glycerolipids from the Traditional Chinese Medicine of Syngnathus acus (Hai-Long).

Two new glycerolipids, syngaculipids A and B (1 and 2), one first naturally occurring metabolite (8), together with five known compounds (3-7) were isolated from the AcOEt fraction of Syngnathus acus L. (Hai-Long). Their structures were elucidated by comprehensive spectral analyses involving UV, IR, MS, 1D and 2D NMR spectra and ECD calculations. All the isolated compounds were evaluated for their cytotoxicity against A549 and HCT-116 cell lines. Compound 8 exhibited moderate cytotoxicity with IC50 values of 34.5 and 38.9 µM on the A549 and HCT-116 cell lines, respectively.

The genome sequence of the greater pipefish, Syngnathus acus (Linnaeus, 1758).

We present a genome assembly from an individual Syngnathus acus (the greater pipefish; Chordata; Actinopteri; Syngnathiformes; Syngnathidae). The genome sequence is 359.2 megabases in span. Most of the assembly is scaffolded into 22 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 16.5 kilobases in length.

Ecological Traits and Trophic Plasticity in The Greater Pipefish Syngnathus acus in the NW Iberian Peninsula.

The great pipefish Syngnathus acus is one of the most representative European syngnathids, being highly associated with seagrass and macroalgal beds. Surprisingly, the ecology of this large ovoviviparous marine fish has received scanty attention. The population inhabiting three sites on Cíes Archipelago (Atlantic Islands National Park, NW Spain) was monitored in 2017-2018 for spatial and temporal changes in abundances, reproduction traits, trophic niche occupancy, and dietary regimes across reproduction states, through an isotopic (δ13C and δ15N) approach. Abundances were highly variable across seasons and sites, decreasing significantly from mid-autumn. The population consisted almost exclusively of large adults that migrate by the end of the breeding season, which extended from mid-spring to summer. Operational sex ratios suggest that the species is sex-role reversed. S. acus is a secondary consumer (Trophic position = 3.36 ± 0.05), preferring amphipods but displaying annual and seasonal dietary plasticity. Mature fish were less selective than immatures (especially females), with a higher preference for amphipods (36-68%) in the former. The second most-preferred prey were carideans, copepods, or isopods, depending on the year and the reproduction state. Overall, the wider trophic niches in females and immature specimens compared to males and mature fish would indicate a higher variability in both the use of prey resources and/or their origin. The present study highlights the trophic plasticity and unique features of S. acus population in the Cíes Archipelago, especially regarding the outstanding size of the fish and the exceptional occurrence of breeders.

Effect of traditional Chinese medicine Syngnathus on D-galactose-induced learning and memory impairment in aging mice / 药学实践杂志

Objective To study the effect of traditional Chinese medicine, Syngnathus on learning and memory impairment induced by D-galactose in aging mice and its mechanism of action. Methods HPLC was used to determine the content of DHA, the active ingredient in anti-learning and memory impairment in Syngnathus. The aging mouse model was prepared by intraperitoneal injection of D-galactose (D-gal). Morris water maze test and Western blot were used to detect the ability of learning and memory, biochemical indicators and protein expression related to oxidative damage in the hippocampus, and to explore the protective effect and mechanism of Syngnathus on learning and memory impairment in aging mice. Results HPLC results showed that the DHA content in Syngnathus was 7.761 3 mg/g (calculated as crude drug), accounting for about 47% of the total composition. Morris water maze results showed that Syngnathus could reduce the escape latency of learning and memory-impaired aging mice and increase the target quadrant swimming time, the proportion of swimming distance and the number of times of crossing the platform, and improve the learning and memory impairment of mice. In addition, Syngnathus can activate the AKT/FOXO1/SOD2 signaling pathway in the hippocampus of aging mice with learning and memory impairment, promote the expression of oxidative stress pathway-related proteins, and improve the learning and memory impairment in aging mice by reducing the degree of oxidative damage in the hippocampus of aging mice. Conclusion This study found that Syngnathus is rich in DHA, which has the effect of improving learning and memory impairment induced by D-galactose in aging mice, and preliminarily clarified that its mechanism of action is related to anti-oxidation. Experimental evidence is provided.

The population genomics of repeated freshwater colonizations by Gulf pipefish.

How organisms adapt to the novel challenges imposed by the colonization of a new habitat has long been a central question in evolutionary biology. When multiple populations of the same species independently adapt to similar environmental challenges, the question becomes whether the populations have arrived at their adaptations through the same genetic mechanisms. In recent years, genetic techniques have been used to tackle these questions by investigating the genome-level changes underlying local adaptation. Here, we present a genomic analysis of colonization of freshwater habitats by a primarily marine fish, the Gulf pipefish (Syngnathus scovelli). We sample pipefish from four geographically distinct freshwater locations and use double-digest restriction site associated DNA sequencing to compare them to 12 previously studied saltwater populations. The two most geographically distant and isolated freshwater populations are the most genetically distinct, although demographic analysis suggests that these populations are experiencing ongoing migration with their saltwater neighbours. Additionally, outlier regions were found genome-wide, showing parallelism across ecotype pairs. We conclude that these multiple freshwater colonizations involve similar genomic regions, despite the large geographical distances and different underlying mechanisms. These similar patterns are probably facilitated by the interacting effects of intrinsic barriers, gene flow among populations and ecological selection in the Gulf pipefish.

The evolution of ecological specialization across the range of a broadly distributed marine species.

Ecological specialization is an important engine of evolutionary change and adaptive radiation, but empirical evidence of local adaptation in marine environments is rare, a pattern that has been attributed to the high dispersal ability of marine taxa and limited geographic barriers to gene flow. The broad-nosed pipefish, Syngnathus typhle, is one of the most broadly distributed syngnathid species and shows pronounced variation in cranial morphology across its range, a factor that may contribute to its success in colonizing new environments. We quantified variation in cranial morphology across the species range using geometric morphometrics, and tested for evidence of trophic specialization by comparing individual-level dietary composition with the community of prey available at each site. Although the diets of juvenile pipefish from each site were qualitatively similar, ontogenetic shifts in dietary composition resulted in adult populations with distinctive diets consistent with their divergent cranial morphology. Morphological differences found in nature are maintained under common garden conditions, indicating that trophic specialization in S. typhle is a heritable trait subject to selection. Our data highlight the potential for ecological specialization in response to spatially variable selection pressures in broadly distributed marine species.

Syngnathus acus in Herbal Markets and Zoological Origin of Syngnathus in China Pharmacopoeia / 中国实验方剂学杂志

Objective: Syngnathus has long been used as an important traditional animal medicine in China,but many syngnathus-like animals also used as Hailong in herbal markets. This study aims to define the zoological origin of Syngnathus in China Pharmacopoeia. Method: Herbalogical records,particularly pictures and photographs of ancient literatures, Syngnathus specimens in museum were stidued to determine the zoological origin of Syngnathus in Chinese herbal medical classics and China Pharmacopoeia. Result: Based on the morphological and DNA sequencing,all the commercial "S. acus" originated from Syngnathus schlegeli (Kaup,1856).Feature description of "S. acus" in China Pharmacopoeia also conformed to S. schlegeli. S. acus in China may be a misidentification of S. schlegeli. Conclusion: Syngnathus in China Pharmacopoeia originates from Solegnathus hardwickii (Gray,1830),Syngnathoides biaculeatus (Bloch,1785) or Syngnathus schlegeli (Kaup,1856).It is suggested to add identification methods of "Hailong", especially molecular identification methods in China Pharmacopoeia,in order to improve quality control standards of Syngnathus.

Complete mitochondrial genome of the larval Syngnathus schlegeli (Gasterosteiformes, Syngnathidae) from Yangtze estuary and the phylogenetic relationship of genus Syngnathus.

The complete mitochondrial genome of the larval Syngnathus schlegeli collected from Yangtze estuary was determined by next-generation sequencing. The mitogenome is a circular molecule 16,465 bp in length, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a control region. The TAS, central CSB and CSB were detected in the control region. The gene contents of the mitogenome are identical to those observed in most marine bony fishes. The NJ phylogenetic tree showed that S. schlegeli clustered in a branch close to the species from the same genus.

Substantial differences in bias between single-digest and double-digest RAD-seq libraries: A case study.

The trade-offs of using single-digest vs. double-digest restriction site-associated DNA sequencing (RAD-seq) protocols have been widely discussed. However, no direct empirical comparisons of the two methods have been conducted. Here, we sampled a single population of Gulf pipefish (Syngnathus scovelli) and genotyped 444 individuals using RAD-seq. Sixty individuals were subjected to single-digest RAD-seq (sdRAD-seq), and the remaining 384 individuals were genotyped using a double-digest RAD-seq (ddRAD-seq) protocol. We analysed the resulting Illumina sequencing data and compared the two genotyping methods when reads were analysed either together or separately. Coverage statistics, observed heterozygosity, and allele frequencies differed significantly between the two protocols, as did the results of selection components analysis. We also performed an in silico digestion of the Gulf pipefish genome and modelled five major sources of bias: PCR duplicates, polymorphic restriction sites, shearing bias, asymmetric sampling (i.e., genotyping fewer individuals with sdRAD-seq than with ddRAD-seq) and higher major allele frequencies. This combination of approaches allowed us to determine that polymorphic restriction sites, an asymmetric sampling scheme, mean allele frequencies and to some extent PCR duplicates all contribute to different estimates of allele frequencies between samples genotyped using sdRAD-seq versus ddRAD-seq. Our finding that sdRAD-seq and ddRAD-seq can result in different allele frequencies has implications for comparisons across studies and techniques that endeavour to identify genomewide signatures of evolutionary processes in natural populations.

Genome-wide selection components analysis in a fish with male pregnancy.

A major goal of evolutionary biology is to identify the genome-level targets of natural and sexual selection. With the advent of next-generation sequencing, whole-genome selection components analysis provides a promising avenue in the search for loci affected by selection in nature. Here, we implement a genome-wide selection components analysis in the sex role reversed Gulf pipefish, Syngnathus scovelli. Our approach involves a double-digest restriction-site associated DNA sequencing (ddRAD-seq) technique, applied to adult females, nonpregnant males, pregnant males, and their offspring. An FST comparison of allele frequencies among these groups reveals 47 genomic regions putatively experiencing sexual selection, as well as 468 regions showing a signature of differential viability selection between males and females. A complementary likelihood ratio test identifies similar patterns in the data as the FST analysis. Sexual selection and viability selection both tend to favor the rare alleles in the population. Ultimately, we conclude that genome-wide selection components analysis can be a useful tool to complement other approaches in the effort to pinpoint genome-level targets of selection in the wild.

The genome of the Gulf pipefish enables understanding of evolutionary innovations.

BACKGROUND: Evolutionary origins of derived morphologies ultimately stem from changes in protein structure, gene regulation, and gene content. A well-assembled, annotated reference genome is a central resource for pursuing these molecular phenomena underlying phenotypic evolution. We explored the genome of the Gulf pipefish (Syngnathus scovelli), which belongs to family Syngnathidae (pipefishes, seahorses, and seadragons). These fishes have dramatically derived bodies and a remarkable novelty among vertebrates, the male brood pouch. RESULTS: We produce a reference genome, condensed into chromosomes, for the Gulf pipefish. Gene losses and other changes have occurred in pipefish hox and dlx clusters and in the tbx and pitx gene families, candidate mechanisms for the evolution of syngnathid traits, including an elongated axis and the loss of ribs, pelvic fins, and teeth. We measure gene expression changes in pregnant versus non-pregnant brood pouch tissue and characterize the genomic organization of duplicated metalloprotease genes (patristacins) recruited into the function of this novel structure. Phylogenetic inference using ultraconserved sequences provides an alternative hypothesis for the relationship between orders Syngnathiformes and Scombriformes. Comparisons of chromosome structure among percomorphs show that chromosome number in a pipefish ancestor became reduced via chromosomal fusions. CONCLUSIONS: The collected findings from this first syngnathid reference genome open a window into the genomic underpinnings of highly derived morphologies, demonstrating that de novo production of high quality and useful reference genomes is within reach of even small research groups.

Population genomics reveals multiple drivers of population differentiation in a sex-role-reversed pipefish.

A major goal of molecular ecology is to identify the causes of genetic and phenotypic differentiation among populations. Population genomics is suitably poised to tackle these key questions by diagnosing the evolutionary mechanisms driving divergence in nature. Here, we set out to investigate the evolutionary processes underlying population differentiation in the Gulf pipefish, Syngnathus scovelli. We sampled approximately 50 fish from each of 12 populations distributed from the Gulf coast of Texas to the Atlantic coast of Florida and performed restriction-site-associated DNA sequencing to identify SNPs throughout the genome. After imposing quality and stringency filters, we selected a panel of 6348 SNPs present in all 12 populations, 1753 of which were not physically linked. We identified a genome-wide pattern of isolation by distance, in addition to a more substantial genetic break separating populations in the Gulf of Mexico from those in the Atlantic. We also used several divergence outlier approaches and tests for genotype-environment correlations to identify 400 SNPs putatively involved in local adaptation. Patterns of phenotypic differentiation and variation diverged from the overall genomic pattern, suggesting that selection, phenotypic plasticity or demographic factors may be shaping phenotypes in distinct populations. Overall, our results suggest that population divergence is driven by a variety of factors in S. scovelli, including neutral processes and selection on multiple traits.

Sex ratio and density affect sexual selection in a sex-role reversed fish.

Understanding how demographic processes influence mating systems is important to decode ecological influences on sexual selection in nature. We manipulated sex ratio and density in experimental populations of the sex-role reversed pipefish Syngnathus typhle. We quantified sexual selection using the Bateman gradient (ßss'), the opportunity for selection (I), and sexual selection (Is), and the maximum standardized sexual selection differential (smax'). We also measured selection on body length using standardized selection differentials (s') and mating differentials (m'), and tested whether the observed I and Is differ from values obtained by simulating random mating. We found that I, Is, and s'max, but not ßss', were higher for females under female than male bias and the opposite for males, but density did not affect these measures. However, higher density decreased sexual selection (m' but not s') on female length, but selection on body length was not affected by sex ratio. Finally, Is but not I was higher than expected from random mating, and only for females under female bias. This study demonstrates that both sex ratio and density affect sexual selection and that disentangling interrelated demographic processes is essential to a more complete understanding of mating behavior and the evolution of mating systems.

Infrared fingerprint analysis of Syngnathus's ethanol extracts coupled with cluster analysis, principal component analysis and discriminant analysis / 中国药学杂志

OBJECTIVE: To establish a validated infrared spectrum method coupled with cluster analysis, principal component a-nalysis and discriminant analysis for identifying different kinds of Syngnathus. METHODS: Fourier transform infrared (FTIR) spectrometer was performed on the ethanol extracts from 33 samples of Syngnathus collected from different geographical locations. Similarity analysis and cluster analysis were used to establish the reference fingerprint spectra, and principal component analysis and discriminant analysis were used for identifying different kinds of Syngnathus. RESULTS: The experimental results indicated that the samples of same species had the similar characteristic peaks of infrared spectra and could be clustered together. Based on the result of principal component analysis, the absorption peaks(3010.4-3006.5 cm-1, 1745.3-1741.4 cm-1, 1467.6-1463.7 cm-1, 1417.4-1413.6 cm-1, 1168.7-1164.8 cm-1, 723.2-719.3 cm-1, 2925.5-2919.7 cm-1, 2854.2-2850.3 cm-1) were the main characteristic peaks and were used to develop the discrimination function for distinguishing different species of Syngnathus. The accuracy of the discrimination function could reach 98.75%. The established method in the experiment had a good stability, precision and reproducibility, and was a very reliable and useful method for distinguishing different species and assessment of the quality of Syngnathus. CONCLUSION: The established IR fingerprints of Syngnathus's ethanol extracts coupled with mathematical statistics theory could be applied to identify different kinds of Syngnathus. But more importantly, the research job provides a new thought for traditional Chinese medicine identification by using mathematical model.

Identification of active components in Syngnathus acus by HILIC-ESI-TOF/MS and study on their specific fingerprint chromatograms / 中草药

Objective: To develop a new method based on hydrophilic interaction chromatography-electrospray ionization-time of flight-mass spectrometry (HILIC-DAD-ESI-TOF/MS) for the rapid identification of the active components in Syngnathus acus and the development of their specific fingerprint chromatograms. Methods: Samples were extracted by accelerated solvent extraction, and the extraction conditions were optimized. The developed HILIC-DAD-ESI-TOF/MS method was used to identify the components in water extract from S. acus, and a chromatographic fingerprint based on HILIC analysis was established. Results: Ten compounds in S. acus extract could be primarily identified by HILIC-DAD-ESI-TOF/MS on-line detection, in which seven nucleosides were determined. The HPLC characteristic fingerprint was established on the basis of analysis on the multi batches of S. acus, which could be used to evaluate the quality of S. acus combined with similarity calculation. Conclusion: This method is simple and rapid, and is a powerful tool for the identification of S. acus.

Purification, characterization and antitumor activities of a new protein from Syngnathus acus, an officinal marine fish.

Discovery and development of new antitumor agents from abundant marine fish are attracting an increasing interest. In the present study, we extracted and purified a novel antitumor protein Syngnathusin from the whole body of Syngnathus acus L., a precious marine fish traditionally used for tumors. Syngnathusin was comprised of 16 kinds of amino acids, mainly acidic amino acids. Its molecular weight was 67.3 kDa and its isoelectric point was 4.57. The N-terminal amino acid sequence of Syngnathusin was determined to be Lys-Arg-Asp-Leu-Gly-Phe-Val-Asp-Glu-Ile-Ser-Ala-His-Tyr and showed no significant homology with the known proteins. Syngnathusin could significantly inhibit the growth of A549 and CCRF-CEM cells. However, the obvious proliferation inhibition against human non-tumor cell lines was not observed. Flow cytometry, morphologic assessment and comet assay revealed that Syngnathusin could induce apoptosis in A549 and CCRF-CEM cells and strongly cooperated with MTX. Syngnathusin could inhibit the growth of S180 tumor transplanted in mice. Syngnathusin may be developed as a novel, selective and effective antineoplastic agent.

Skeletal Organization of Caudal Fin in Syngnathus abaster (Osteichthyes, Syngnathidae) / Organización Esqueletal de la Paleta Caudal en Syngnathus abaster (Osteichthyes, Syngnathidae)

The caudal skeleton is one of the most important tools to evaluate teleostean interrelationships, but just the anatomy of few species have been investigated. Black-striped pipefish (Syngnathus abaster) has never been examined for its caudal morphology. Here, red alizaryn is applied as specific staining for calcified structures, providing a better understanding of caudal skeleton organization. Our results and interpretation just partially fit with previous knowledge on other Syngnathus species. This emphasizes both the importance of facing same problems with new technics and methodologies, and the existence of a heterogeneous situation between close-related taxa.

El esqueleto caudal es una de las más importantes herramientas para evaluar las interrelaciones de teleósteros, pero la anatomía de pocas especies han sido investigada. Nunca se ha estudiado la morfología de la cauda del pez aguja de río de rayas negras (Syngnathus abaster). Se usó una técnica específica de tinción con alizarina roja, para visualizar estructuras calcificadas, obteniéndose un gran conocimiento de la organización del esqueleto caudal. Los resultados e interpretación de ellos coinciden parcialmente con los hallazgos en otras especies de Syngnathus. En ambos casos se enfatiza la importancia de tratar los problemas con nuevas técnicas y metodologías.

Determination of hypoxanthine and xanthine in Syngnathus by HPLC / 中国海洋药物

Objective To establish a HPLC method for determination of hypoxanthine and xanthine in Syngnathus.Methods A Lichrosper C_(18) Column was used.The mobile phase was methanol-0.1%HAc.Walvelength was 254nm.Results The linear range of hypoxanthine was within 5.91～94.56?g?mL~(-1),r=0.9999,sample recovery rate was 99.22%,RSD=(1.25)%.The linear range of Xanthine was within 2.04~32.64?g?mL~(-1),r=0.9998,sample recovery rate was 98.05%,RSD=1.21%.Conclusion This method has good repeatability and flexibility.It can be used for quality control in production of Syngnathus.

Research on anti-fatigue effect of syngnathus acus L / 中国海洋药物

The study analyzed the compositions of Syngnathus acus L and discussed its anti-fatigue effect. Prepared lipid and enzymatic hydrolysate. The animal experiment methods are such as followed-(1)Enduring capacity experiment. (2)Determining LA (Lactic Acid) concentrations before and after swimming sports. (3)Determining the content of muscle glyco-gen and hepatic glycogen of mice. These experiments showed that lipid and enzymatic hydrolysate are both able to prolong swimming time of mice (P