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1.
We examined the genetic variation and phylogeographic relationships among 10 populations of Lunella granulata from mainland China, Penghu Archipelago, Taiwan Island, and Japan using mitochondrial COI and 16S markers. A total of 45 haplotypes were obtained in 112 specimens, and relatively high levels of haplotype diversity (h = 0.903) and low levels of nucleotide diversity (π = 0.0046) were detected. Four major phylogenetic lineage clusters were revealed and were concordant with their geographic distribution, agreeing with the haplotype network. These results suggested that geographic barrier isolating effects were occurring among the populations. This hypothesis was also supported by a significant genetic differentiation index (FST = 0.709) and by a spatial analysis of molecular variance (SAMOVA) analysis. A mismatch distribution analysis, neutrality tests and Bayesian skyline plots found a single significant population expansion. This expansion occurred on the coast of mainland China before 20–17 ka. Consequently, although the dispersal ability of the planktonic stage and the circulation of ocean currents generally promote genetic exchanges among populations, L. granulata has tended to maintain distinct genetic groups that reflect the respective geographic origins of the constituent lineages. Although the circulation of ocean currents, in principle, may still play a role in determining the genetic composition of populations, long-distance migration between regions is difficult even at the planktonic stage.  相似文献   

2.
Barnacles of the genus Neoverruca are abundant near deep-sea hydrothermal vents of the northwestern Pacific Ocean, and are useful for understanding processes of population formation and maintenance of deep-sea vent faunas. Using next-generation sequencing, we isolated 12 polymorphic microsatellite loci from Neoverruca sp., collected in the Okinawa Trough. These microsatellite loci revealed 2–19 alleles per locus. The expected and observed heterozygosities ranged from 0.286 to 1.000 and 0.349 to 0.935, respectively. Cross-species amplification showed that 9 of the 12 loci were successfully amplified for Neoverruca brachylepadoformis in the Mariana Trough. A pairwise FST value calculated using nine loci showed significant genetic differentiation between the two species. Consequently, the microsatellite markers we developed will be useful for further population genetic studies to elucidate genetic diversity, differentiation, classification, and evolutionary processes in the genus Neoverruca.  相似文献   

3.
Recent genome-wide association studies identified single nucleotide polymorphisms (SNPs) on the chromosome 9p21.3 conferring the risk for CAD (coronary artery disease) in individuals of Caucasian ancestry. We performed a genetic association study to investigate the effect of 12 candidate SNPs within 9p21.3 locus on the risk of CAD in the Saudi population of the Eastern Province of Saudi Arabia. A total of 250 Saudi CAD patients who had experienced an myocardial infarction (MI) and 252 Saudi age-matched healthy controls were genotyped using TaqMan assay. Controls with evidenced lack of CAD provided 90% of statistical power at the type I error rate of 0.05. Five percent of the results were rechecked for quality control using Sanger sequencing, the results of which concurred with the TaqMan genotyping results. Association analysis of 12 SNPs indicated a significant difference in the genotype distribution for four SNPs between cases and controls (rs564398 p = 0.0315, χ2 = 4.6, odds ratio (OD) = 1.5; rs4977574 p = 0.0336, χ2 = 4.5, OD = 1.4; rs2891168 p = 1.85 × 10 − 10, χ2 = 40.6, OD = 2.1 and rs1333042 p = 5.14 × 10 − 9, χ2 = 34.1, OD = 2.2). The study identified three protective haplotypes (TAAG p = 1.00 × 10 − 4; AGTA p = 0.022 and GGGCC p = 0.0175) and a risk haplotype (TGGA p = 2.86 × 10 − 10) for the development of CAD. This study is in line with others that indicated that the SNPs located in the intronic region of the CDKN2B-AS1 gene are associated with CAD.  相似文献   

4.
Knowledge about the population genetic variation of the endangered orchid, Cypripedium japonicum, is conducive to the development of conservation strategies. Here, we examined the levels and partitioning of inter-simple sequence repeat (ISSR) diversity (109 loci) in five populations of this orchid to gain insight into its genetic variation and population structure in Eastern and Central China. It harbored considerably lower levels of genetic diversity both at the population (percentage of polymorphic loci (PPL) = 11.19%, Nei’s gene diversity (H) = 0.0416 and Shannon’s information index (I) = 0.0613) and species level (PPL = 38.53%, H = 0.1273 and I = 0.1928) and a significantly higher degree of differentiation among populations (the proportion of the total variance among populations (Φpt) = 0.698) than those typical of ISSR-based studies in other orchid species. Furthermore, the Nei’s genetic distances between populations were independent of the corresponding geographical distances. Two main clusters are shown in an arithmetic average (UPGMA) dendrogram, which is in agreement with the results of principal coordinate analysis (PCoA) analysis and the STRUCTURE program. In addition, individuals within a population were more similar to each other than to those in other populations. Based on the genetic data and our field survey, the development of conservation management for this threatened orchid should include habitat protection, artificial gene flow and ex situ measures.  相似文献   

5.
Stroke is currently the leading cause of functional impairments worldwide. Folate supplementation is inversely associated with risk of ischemic stroke. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme involved in folate metabolism. The aim of this study is to examine whether genetic variants in MTHFR gene are associated with the risk of ischemic stroke and fasting total serum homocysteine (tHcy) level. We genotyped nine tag SNPs in the MTHFR gene in a case-control study, including 543 ischemic stroke cases and 655 healthy controls in China. We found that subjects with the rs1801133 TT genotype and rs1801131 CC genotype had significant increased risks of ischemic stroke (adjusted odds ratio (OR) = 1.82, 95% confidence interval (CI): 1.27–2.61, p = 0.004; adjusted OR = 1.99, 95% CI: 1.12–3.56, p = 0.01) compared with subjects with the major alleles. Haplotype analysis also found that carriers of the MTHFR CTTCGA haplotype (rs12121543-rs13306553-rs9651118-rs1801133-rs2274976-rs1801131) had a significant reduced risk of ischemic stroke (adjusted OR = 0.53, 95% CI: 0.35–0.82) compared with those with the CTTTGA haplotype. Besides, the MTHFR rs1801133 and rs9651118 were significantly associated with serum levels of tHcy in healthy controls (p < 0.0001 and p = 0.02). These findings suggest that variants in the MTHFR gene may influence the risk of ischemic stroke and serum tHcy.  相似文献   

6.
Xyloglucan endo-transglycosylases (XETs) modify the xyloglucan-cellulose framework of plant cell walls and, thus, affect cell wall expansion and strength. Dissecting the mechanism by which natural variation in XETs affects wood properties can inform breeding efforts to improve wood quality and yield traits. To this end, we isolated a full-length PtoXET16A cDNA clone from Populus tomentosa. Real-time PCR analysis showed that PtoXET16A was maximally expressed in the root, followed by phloem, cambium, and developing xylem, suggesting that PtoXET16A plays important roles in the development of vascular tissues. Nucleotide diversity and linkage disequilibrium analysis revealed that PtoXET16A has high single nucleotide polymorphism (SNP) diversity (π = 0.01266 and θw = 0.01392) and low linkage disequilibrium (r2 ≥ 0.1, within 900 bp). SNP- and haplotype-based association analyses of 426 individuals from a natural population indicated that nine SNPs (including two non-synonymous markers and one splicing variant) (p ≤ 0.05, false discovery rate Q ≤ 0.01), and nine haplotypes (p ≤ 0.05) were significantly associated with growth and wood properties, each explaining from 3.40%–10.95% of phenotypic variance. This work shows that examination of allelic variation and linkage disequilibrium by a candidate-gene-based approach can help to decipher the genetic basis of wood formation. Moreover, the SNP markers identified in this study can potentially be applied for marker-assisted selection to improve growth and wood-property traits in Populus.  相似文献   

7.
Two new norsesquiterpenoids, solanerianones A and B (1–2), together with nine known compounds, including four sesquiterpenoids, (−)-solavetivone (3), (+)-anhydro-β-rotunol (4), solafuranone (5), lycifuranone A (6); one alkaloid, N-trans-feruloyltyramine (7); one fatty acid, palmitic acid (8); one phenylalkanoid, acetovanillone (9), and two steroids, β-sitosterol (10) and stigmasterol (11) were isolated from the n-hexane-soluble part of the roots of Solanum erianthum. Their structures were elucidated on the basis of physical and spectroscopic data analyses. The anti-inflammatory activity of these isolates was monitored by nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW264.7 cells. The cytotoxicity towards human lung squamous carcinoma (CH27), human hepatocellular carcinoma (Hep 3B), human oral squamous carcinoma (HSC-3) and human melanoma (M21) cell lines was also screened by using an MTT assay. Of the compounds tested, 3 exhibited the strongest NO inhibition with the average maximum inhibition (Emax) at 100 μM and median inhibitory concentration (IC50) values of 98.23% ± 0.08% and 65.54 ± 0.18 μM, respectively. None of compounds (1–9) was found to possess cytotoxic activity against human cancer cell lines at concentrations up to 30 μM.  相似文献   

8.
Two low oxygen sensors, Egl nine homolog 1 (EGLN1) and hypoxia-inducible factor 1-α inhibitor (HIF-1AN), play pivotal roles in the regulation of HIF-1α, and high altitude adaption may be involved in the pathology of acute mountain sickness (AMS). Here, we aimed to analyze single nucleotide polymorphisms (SNPs) in the untranslated regions of the EGLN1 and HIF-1AN genes and SNPs chosen from a genome-wide adaptation study of the Han Chinese population. To assess the association between EGLN1 and HIF-1AN SNPs and AMS in a Han Chinese population, a case–control study was performed including 190 patients and 190 controls. In total, thirteen SNPs were genotyped using the MassARRAY® MALDI-TOF system. Multiple genetic models were tested; The Akaike’s information criterion (AIC) and Bayesian information criterion (BIC) values indicated that the dominant model may serve as the best-fit model for rs12406290 and rs2153364 of significant difference. However, these data were not significant after Bonferroni correction. No significant association was noted between AMS and rs12757362, rs1339894, rs1361384, rs2009873, rs2739513 or rs2486729 before and after Bonferroni correction. Further haplotype analyses indicated the presence of two blocks in EGLN1; one block consists of rs12406290-rs2153364, located upstream of the EGLN1 gene. Carriers of the “GG” haplotype of rs12406290-rs2153364 exhibited an increased risk of AMS after adjustments for age and smoking status. However, no significant association was observed among HIF-1AN 3''-untranslated region (3''-UTR) polymorphisms, haplotype and AMS. Our study indicates that variants in the EGLN1 5''-UTR influence the susceptibility to AMS in a Han Chinese population.  相似文献   

9.
Two new triterpenoids, 2α,3β-dihydroxyolean-11,13(18)-dien-19β,28-olide (1) and 3β,5β-dihydroxyglutinol (2), together with eight known compounds (3–10) were isolated from the roots of Rhaphiolepis indica var. tashiroi (Rosaceae). The structures of 1–10 were determined by spectroscopic techniques. Among these isolates, 2α,3β-dihydroxyolean-13(18)-en-28-oic acid (9) exhibited inhibitory effect on N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide production, with an IC50 value of 16.50 μM.  相似文献   

10.
Myostatin (MSTN) is a member of the transforming growth factor-β superfamily that negatively regulates skeletal muscle development and growth. In the present study, partial genomic fragments of MSTN were screened for single nucleotide polymorphisms (SNPs) in selected common carp individuals from wild populations, and two SNPs in intron 2 (c.371 + 749A > G, c.371 + 781T > C) and two synonymous SNPs in exon 3 (c.42A > G, c.72C > T) were identified. Genotyping by direct sequencing of polymerase chain reaction (PCR) products for these four SNPs were performed in 162 individuals from a commercial hatchery population. Association analysis showed that two SNPs in exon 3 were significantly associated with body weight (BW) and condition factor (K), and haplotype analyses revealed that haplotype H7H8 showed better growth performance. Our results demonstrated that some of the SNPs in MSTN may have positive effects on growth traits and suggested that MSTN could be a candidate gene for growth and marker-assisted selection in common carp.  相似文献   

11.
In parallel to medical treatment of ovarian cancer, methods for the early detection of cancer tumors are being sought. In this contribution, the use of non-invasive static (SLS) and dynamic light scattering (DLS) for the characterization of extracellular nanoparticles (ENPs) in body fluids of advanced serous ovarian cancer (OC) and benign gynecological pathology (BP) patients is demonstrated and critically evaluated. Samples of plasma and ascites (OC patients) or plasma, peritoneal fluid, and peritoneal washing (BP patients) were analyzed. The hydrodynamic radius (Rh) and the radius of gyration (Rg) of ENPs were calculated from the angular dependency of LS intensity for two ENP subpopulations. Rh and Rg of the predominant ENP population of OC patients were in the range 20–30 nm (diameter 40–60 nm). In thawed samples, larger particles (Rh mostly above 100 nm) were detected as well. The shape parameter ρ of both particle populations was around 1, which is typical for spherical particles with mass concentrated on the rim, as in vesicles. The Rh and Rg of ENPs in BP patients were larger than in OC patients, with ρ ≈ 1.1–2, implying a more elongated/distorted shape. These results show that SLS and DLS are promising methods for the analysis of morphological features of ENPs and have the potential to discriminate between OC and BP patients. However, further development of the methodology is required.  相似文献   

12.
Four new labdane-type diterpenoids: hedychicoronarin (1), peroxycoronarin D (2), 7β-hydroxycalcaratarin A (3), and (E)-7β-hydroxy-6-oxo-labda-8(17),12-diene-15,16-dial (4), have been isolated from the rhizomes of Hedychium coronarium, together with 13 known compounds (5–17). The structures of these new compounds were determined through spectroscopic and MS analyses. Compounds 3, 5, 6, and 10 exhibited inhibition (IC50 values ≤4.52 μg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leucyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 3–6, 10, and 11 inhibited fMLP/CB-induced elastase release with IC50 values ≤6.17 μg/mL.  相似文献   

13.
Two eudesmane sesquiterpenoids, verticillatol (1) and 5α-acetoxy-4(14)-eudesmene-1β-ol (2) and two cembrane diterpenoids, (–)-leptodiol acetate (3) and sinulacembranolide A (4) were isolated from the octocoral Sinularia gaweli and compounds 2–4 are new isolates. The structures of new terpenoids 2–4 were elucidated by spectroscopic methods and by comparison the spectral data with those of known analogues. Terpenoid 4 was found to inhibit the accumulation of the pro-inflammatory inducible nitric oxide synthase (iNOS) protein of the lipopolysaccharide (LPS)-stimulated RAW264.7 marcophage cells.  相似文献   

14.
Four new secondary metabolites, 3α-((E)-Dodec-1-enyl)-4β-hydroxy-5β-methyldihydrofuran-2-one (1), linderinol (6), 4′-O-methylkaempferol 3-O-α-l-(4″-E-p-coumaroyl)rhamnoside (11) and kaempferol 3-O-α-l-(4″-Z-p-coumaroyl) rhamnoside (12) with eleven known compounds—3-epilistenolide D1 (2), 3-epilistenolide D2 (3), (3Z,4α,5β)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (4), (3E,4β,5β)-3-(dodec-11-ynylidene)-4-hydroxy-5-methylbutanolide (5), matairesinol (7), syringaresinol (8), (+)-pinoresinol (9), salicifoliol (10), 4″-p-coumaroylafzelin (13), catechin (14) and epicatechin (15)—were first isolated from the aerial part of Lindera akoensis. Their structures were determined by detailed analysis of 1D- and 2D-NMR spectroscopic data. All of the compounds isolated from Lindera akoensis showed that in vitro anti-inflammatory activity decreases the LPS-stimulated production of nitric oxide (NO) in RAW 264.7 cell, with IC50 values of 4.1–413.8 μM.  相似文献   

15.
Single nucleotide polymorphisms (SNPs) are widely employed in the studies of population genetics, molecular breeding and conservation genetics. In this study, we explored a simple route to develop SNPs from non-model species based on screening the library of single copy nuclear genes (SCNGs). Through application of this strategy in Panax, we identified 160 and 171 SNPs from P. quinquefolium and P. ginseng, respectively. Our results demonstrated that both P. ginseng and P. quinquefolium possessed a high level of nucleotide diversity. The number of haplotype per locus ranged from 1 to 12 for P. ginseng and from 1 to 9 for P. quinquefolium, respectively. The nucleotide diversity of total sites (πT) varied between 0.000 and 0.023 for P. ginseng and 0.000 and 0.035 for P. quinquefolium, respectively. These findings suggested that this approach is well suited for SNP discovery in non-model organisms and is easily employed in standard genetics laboratory studies.  相似文献   

16.
The variable domain 1 (VD1) domain of the control region and a small segment of the rrnaL gene of the F mtDNA type were sequenced and analyzed in 174 specimens of Mytilus galloprovincialis. Samples were collected from eight locations in four Central-Eastern (CE) Mediterranean countries (Italy, Croatia, Greece and Turkey). A new primer, specific for the F mtDNA type, was designed for the sequencing procedure. In total 40 different haplotypes were recorded, 24 of which were unique. Aside from the two populations situated in Thermaikos gulf (Northern Aegean, Greece), relatively high levels of haplotype and nucleotide diversity were estimated for both Central and Eastern Mediterranean populations. Eight out of the 40 haplotypes were shared by at least three populations while two of them were found in all populations. ΦST and cluster analysis revealed lack of structuring among CE Mediterranean populations with the exception of those located at the Sea of Marmara and Croatian coast which were highly differentiated. Apart from the species’ inherit dispersal ability, anthropogenic activities, such as the repeated translocations of mussel spat, seem to have played an important role in shaping the current genetic population structure of CE M. galloprovincialis mussels.  相似文献   

17.
18.
Recent genome-wide association studies (GWASs) have identified 15q25.1 as a lung cancer susceptibility locus. Here, we sought to explore the direct carcinogenic effects of genetic variants in this region on the risk of developing lung adenocarcinoma (ADC). Five common SNPs (rs8034191, rs16969968, rs1051730, rs938682, and rs8042374) spanning the 15q25.1 locus were assayed in a case-control study examining a cohort of 301 lung ADCs and 318 healthy controls. Stratification analysis by gender, smoking status, and tumor, node, metastasis (TNM) classification, was performed. In addition, sections from ADC tissue and normal tissue adjacent to tumors were stained with an anti-CHRNA3 (cholinergic receptor nicotinic α3) antibody by immunohistochemistry in 81 cases. Our results demonstrate that rs8042374, a variant of the CHRNA3 gene, is associated with an increased risk of ADC with an OR of 1.76 (95% CI: 1.17–2.65, p = 0.024). This variant was linked to a greater risk of ADC in female nonsmokers (OR (95% CI): 1.81 (1.05–3.12), p = 0.032) and female stage I + II cases (OR (95% CI): 1.92 (1.03–3.57), p = 0.039). Although located within the same gene, rs938682 showed protective effects for smokers, stage III + IV cases, and male stage III + IV cases. Additionally, the CHRNA3 protein level in ADC tissue was slightly higher than in the surrounding normal lung tissue, based on immunohistochemical analysis. Our results suggest that the CHRNA3 polymorphism functions as a genetic modifier of the risk of developing lung ADC in the Chinese population, particularly in nonsmoking females.  相似文献   

19.
The purpose of this work was to evaluate the expression of fatty acid metabolism-related genes in human adipose tissue from moderately obese women. We used qRT-PCR and Western Blot to analyze visceral (VAT) and subcutaneous (SAT) adipose tissue mRNA expression involved in de novo fatty acid synthesis (ACC1, FAS), fatty acid oxidation (PPARα, PPARδ) and inflammation (IL6, TNFα), in normal weight control women (BMI < 25 kg/m2, n = 35) and moderately obese women (BMI 30–38 kg/m2, n = 55). In SAT, ACC1, FAS and PPARα mRNA expression were significantly decreased in moderately obese women compared to controls. The downregulation reported in SAT was more pronounced when BMI increased. In VAT, lipogenic-related genes and PPARα were similar in both groups. Only PPARδ gene expression was significantly increased in moderately obese women. As far as inflammation is concerned, TNFα and IL6 were significantly increased in moderate obesity in both tissues. Our results indicate that there is a progressive downregulation in lipogenesis in SAT as BMI increases, which suggests that SAT decreases the synthesis of fatty acid de novo during the development of obesity, whereas in VAT lipogenesis remains active regardless of the degree of obesity.  相似文献   

20.
The Chinese beard eel (Cirrhimuraena chinensis Kaup) is an intertidal fish and a model organism for the study of impacts caused by topological fluctuations during the Pleistocene and current intricate hydrological conditions on fauna living in the coastal areas of China. In this study, we examined the phylogeographical pattern, population genetic profile and demographical history of C. chinensis using mitochondrial DNA (cytochrome b (cyt b) and control region (CR)) from 266 individuals sampled in seven localities across the coastal area of southeastern China. The combined data indicated high levels of haplotype diversity and low levels of nucleotide diversity. Analyses of molecular variance (AMOVA) and FST statistics suggested the absence of a significant population structure across the Chinese coast. Neutrality tests, mismatch distributions and Bayesian skyline plots uniformly indicated a recent population expansion. The phylogeographic structure of C. chinensis may be attributed to past population expansion and long-distance pelagic larval dispersal facilitated by present-day ocean currents.  相似文献   

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