中国近海牡蛎系统分类研究的现状和对策

探讨了中国近海沿岸牡蛎分类的诸多疑难和热点问题,回顾了国内外包括贝类等动物的分子系统发生学研究的主要进展,分析了中国近海牡蛎系统分类目前存在的问题,重点阐述了利用分子标记等手段解决形态相似种的鉴定和种系发生关系等问题的巨大潜力,报道了利用分子标记进行牡蛎分类研究所取得的最新进展。预期经典分类学和分子系统发生学研究的交叉综合,将大力推动中国近海牡蛎的系统分类和系统发生研究的发展。     

Development of genome-wide insertion and deletion markers for maize,based on next-generation sequencing data

Background

Insertions and deletions (indels) are the most abundant form of structural variation in all genomes. Indels have been increasingly recognized as an important source of molecular markers due to high-density occurrence, cost-effectiveness, and ease of genotyping. Coupled with developments in bioinformatics, next-generation sequencing (NGS) platforms enable the discovery of millions of indel polymorphisms by comparing the whole genome sequences of individuals within a species.

Results

A total of 1,973,746 unique indels were identified in 345 maize genomes, with an overall density of 958.79 indels/Mbp, and an average allele number of 2.76, ranging from 2 to 107. There were 264,214 indels with polymorphism information content (PIC) values greater than or equal to 0.5, accounting for 13.39 % of overall indels. Of these highly polymorphic indels, we designed primer pairs for 83,481 and 29,403 indels with major allele differences (i.e. the size difference between the most and second most frequent alleles) greater than or equal to 3 and 8 bp, respectively, based on the differing resolution capabilities of gel electrophoresis. The accuracy of our indel markers was experimentally validated, and among 100 indel markers, average accuracy was approximately 90 %. In addition, we also validated the polymorphism of the indel markers. Of 100 highly polymorphic indel markers, all had polymorphisms with average PIC values of 0.54.

Conclusions

The maize genome is rich in indel polymorphisms. Intriguingly, the level of polymorphism in genic regions of the maize genome was higher than that in intergenic regions. The polymorphic indel markers developed from this study may enhance the efficiency of genetic research and marker-assisted breeding in maize.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1797-5) contains supplementary material, which is available to authorized users.     

The Prevalence and Influence Factors of Inter-Ankle Systolic Blood Pressure Difference in Community Population

Aim

The aim of this study was to investigate the prevalence of interankle systolic blood pressure difference (sIAND) and its influencing factors in community population.

Methods

This study included 2849 (65.1±9.4 y) subjects. Blood pressure (BPs) of four limbs was simultaneously measured with 4 electronic sphygmomanometers after 10 min rest in supine position. The difference of systolic BP (SBP) between two ankles was calculated as DETASBP. The criterion for abnormal sIAND was ≥10 mmHg of absolute DeltaSBP, in which the criterion for 1o sIAND was 10–19 mmHg and for 2o sIAND was ≥20 mmHg. Age, gender, smoking, hypertension, family histories of hypertension and diabetes were recorded. Fasting blood glucose and lipids, circumference of hip and waist, and body mass index (BMI) were measured.

Results

The SBP was higher in the right ankle than in the left ankle (158.9±21.8 vs 157.3±21.6 mmHg, P<0.05) and mean DeltaSBP was 6.08±6.26 mmHg. Similar difference was found in both genders. The prevalence of abnormal was 18.5%, in which, the prevalence 1o sIAND was 15.3% and that of 2o sIAND was 3.1%. Multivariate regression analysis showed that age, waist circumference and blood glucose level were the positive factors for DeltaSBP. The normal upper limit for DeltaSBP was 16.7 mmHg in this population, the prevalence of sIAND by≥16 mmHg was 5.8%.

Conclusion

Aging, hypertension, obesity and abnormal glucose metabolism are positive factors for inter-ankle SBP difference.     

Functional role and immunocytochemical localization of the gamma a and gamma b forms of the Na,K-ATPase gamma subunit

The gamma subunit of the Na,K-ATPase is a member of the FXYD family of type 2 transmembrane proteins that probably function as regulators of ion transport. Rat gamma is present primarily in the kidney as two main splice variants, gamma(a) and gamma(b), which differ only at their extracellular N termini (TELSANH and MDRWYL, respectively; Kuster, B., Shainskaya, A., Pu, H. X., Goldshleger, R., Blostein, R., Mann, M., and Karlish, S. J. D. (2000) J. Biol. Chem. 275, 18441-18446). Expression in cultured cells indicates that both variants affect catalytic properties, without a detectable difference between gamma(a) and gamma(b). At least two singular effects are seen, irrespective of whether the variants are expressed in HeLa or rat alpha1-transfected HeLa cells, i.e. (i) an increase in apparent affinity for ATP, probably secondary to a left shift in E(1) <--> E(2) conformational equilibrium and (ii) an increase in K(+) antagonism of cytoplasmic Na(+) activation. Antibodies against the C terminus common to both variants (anti-gamma) abrogate the first effect but not the second. In contrast, gamma(a) and gamma(b) show differences in their localization along the kidney tubule. Using anti-gamma (C-terminal) and antibodies to the rat alpha subunit as well as antibodies to identify cell types, double immunofluorescence showed gamma in the basolateral membrane of several tubular segments. Highest expression is in the medullary portion of the thick ascending limb (TAL), which contains both gamma(a) and gamma(b). In fact, TAL is the only positive tubular segment in the medulla. In the cortex, most tubules express gamma but at lower levels. Antibodies specific for gamma(a) and gamma(b) showed differences in their cortical location; gamma(a) is specific for cells in the macula densa and principal cells of the cortical collecting duct but not cortical TAL. In contrast, gamma(b) but not gamma(a) is present in the cortical TAL only. Thus, the importance of gamma(a) and gamma(b) may be related to their partially overlapping but distinct expression patterns and tissue-specific functions of the pump that these serve.     

GFP基因在新疆小拟南芥和拟南芥中的表达分析

以质粒pMCB30为模板,扩增GFP基因,连接到载体pCMBIA2300-35S-OCS上,构建过量表达载体p35S:GFP,将其转入农杆菌GV3101.通过农杆菌介导法将p35S:GFP载体分别转入新疆特色植物小拟南芥和拟南芥中.T0代经含有卡那霉素的1/2MS培养基筛选,获得了T1代转基因小拟南芥2株,T1代转基因拟南芥9株.通过激光共聚焦显微镜观察,在转基因小拟南芥和拟南芥的根尖细胞中均可检测到GFP绿色荧光蛋白;对转基因植株进行PCR扩增,均可检测到GFP基因,表明GFP基因已成功转入小拟南芥和拟南芥中.该研究建立了小拟南芥的遗传转化体系,为进一步利用GFP基因和进一步研究小拟南芥的功能基因奠定基础.     

Excitation of Broadband Surface Plasmons with Dye Molecules

Rhodamine B and Rhodamine 6G molecules were doped in polymethyl methacrylate solution. Then a silver film on the glass substrate was spin coated with the mixed solution to get a multilayer film. Under the irradiation of a 532-nm green laser, broadband surface plasmons (SPs) on the silver film were generated due to the coupling between the broadband fluorescence and the SP modes allowed in the multilayer film. From the back focal plane image of a leakage radiation microscopy, propagation constants of SP waves at different wavelengths were derived. Numerical calculations were also carried out and were consistent with the experimental results.