A Class of Lie 2-Algebras in Higher-Order Courant Algebroids

In this paper, we study the relation of the algebraic properties of the higher-order Courant bracket and Dorfman bracket on the direct sum bundle TM⊕∧pT*M for an m-dimensional smooth manifold M, and a Lie 2-algebra which is a “categorified” version of a Lie algebra. We prove that the higher-order Courant algebroids give rise to a semistrict Lie 2-algebra, and we prove that the higher-order Dorfman algebroids give rise to a hemistrict Lie 2-algebra. Consequently, there is an isomorphism from the higher-order Courant algebroids to the higher-order Dorfman algebroids as Lie 2-algebras homomorphism.

Chromosomal mapping of 5S and 18S-5.8S-25S rRNA genes in Saccharina japonica(Phaeophyceae)as visualized by dual-color fluorescence in situ hybridization

It has been reported that there was a linkage of 5S rRNA gene to 18S-5.8S-25S rRNA gene in a few of species in Ochrophyta.In regard to the usual two positions of linked 5S rDNA to the 3′end of 25S rDNA,two pairs of primers were designed for amplification to verify this linkage of two genes in a kelp cultivar of Saccharina japonica,one of species in Ochrophyta.This result supplemented the previous report that 5S rDNA was unlinked to 25S rDNA in this kelp.In order to simultaneously visualize this unlinkage of two genes,dual-color fluorescence in situ hybridization(FISH)technique was applied to the cytogenetics of S.japonica.Dual-color FISH images showed that two and four hybridization signals were present in the kelp gametophyte and sporophyte,respectively,metaphase nuclei hybridized simultaneously with the labeled probes of 18S rDNA and 5S rDNA.Both haploid and diploid karyotypes in decreasing length of chromosomes showed that 18S-5.8S-25S rDNA was localized at the interstitial region of Chromosome 23,whereas 5S rDNA resided at the sub-telomeric region of Chromosome 27.These karyotypes suggested that the kelp nuclear genome had only one locus of each rRNA gene,and their loci on different chromosomes indicated the physical unlinkage of 5S rDNA to 18S-5.8S-25S rDNA in this kelp.Therefore,dual-color FISH seems to be a powerful technique for the discrimination and pairing of chromosomes featured in both small size and nearly identical shape in S.japonica.

Molecular and FISH analysis of 45S rDNA on BAC molecule of Saccharina japonica

IGS is abundant in polymorphism,which is widely used in the analysis of intraspecific genetic diversity and phylogenetic relationships among geographical populations.In this study,the 45S rDNA repeat unit of Saccharina japonica was obtained for the first time by BAC clone sequencing.The total length of the 45S rDNA repeat unit of S.japonica was 8995 bp,including 5420 bp of 18S-5.8S-25S rDNA,and 3575 bp of IGS(Intergenic Spacer),with the GC content of 51.4%.The IGS was composed of a 465 bp of 3′-outer transcribed spacer(ETS),an 874 bp 5′-ETS,and a 2236 bp non-transcribed spacer(NTS),with the GC content of 50.1%.Fiber-FISH(fiber-fluorescence in situ hybridization)analysis of the distribution of 45S rDNA repeat units on the bacterial artificial chromosome illustrated that each fiber had at least five continuously moniliform hybridization signal points.This study provided a new candidate molecular marker for detecting intraspecific polymorphisms of S.japonica.In addition,the successful fiber-FISH analysis of the 45S rDNA on BAC molecule would contribute to the construction of the physical map and map-based cloning of this kelp.

智能DNA水凝胶在生化分析中的应用

作为一种新型的生物大分子软材料, DNA水凝胶近年来成为国内外多学科交叉研究的热点领域之一.基于DNA材料具有可编码性和功能单元丰富的特点,通过合理的序列设计以及多样化的修饰,可以在水凝胶中引入对不同类型刺激特异性响应的功能DNA结构和催化性DNA结构,从而得到具有多种功能的智能DNA水凝胶.这类材料可以在特定外界刺激下发生特异的响应性变化,材料组装具有高精准度的可控性,可满足分子识别、信号转换与放大、可控释放等诸多方面的应用需要,并具有良好的生物相容性和可降解性等优点,在生物医学特别是生化分析中具有重要的应用前景.本文总结了不同类型的智能DNA水凝胶以及其在生化分析方面的典型应用,并对该领域当前重要问题与未来前景进行了讨论与展望.

Full-length mRNA sequencing in Saccharina japonica and identification of carbonic anhydrase genes

The carbonic anhydrases(CAs)are a group of enzymes that play an important role in the absorption and transportation of CO_(2) in Saccharina japonica.They are encoded by a superfamily of genes with seven subtypes that are unrelated in sequence but share conserved function in catalyzing the reversible conversion of CO_(2) and HCO_(3)^(-).Here we have characterized the CA members in the transcriptome of S.japonica using Single-molecule real-time(SMRT)sequencing technology.Approximately 9830.4 megabases from 5,028,003 quality subreads were generated,and they were assembled into 326,512 full-length non-chimeric(FLNC)reads,with an average flnc read length of 2181 bp.After removing redundant sequences,79,010 unique transcripts were obtained of which 38,039 transcripts were successfully annotated.From the full-length transcriptome,we have identified 7 full-length cDNA sequences for CA genes(4α-CAs,1β-CAs and 2γ-CAs)and assessed for their potential functions based on phylogenetic analysis.Characterizations of CAs will provide the ground for future studies to determine the involvement of CAs in inorganic carbon absorption and transportation in S.japonica.

Nonabelian omni-Lie algebroids

In this paper,we study the structure of nonabelian omni-Lie algebroids.Firstly,taking Lie algebroid(E,[·,·]_(E,ρE))as the starting point,a nonabelian omni-Lie algebroid is defined on direct sum bundle DE⊕JE,where DE and JE are,respectively,the gauge Lie algebroid and the jet bundle of vector bundle E,and study its properties.Furthermore,it is concluded that the nonabelian omni-Lie algebroid is a trivial deformation of the omni-Lie algebroid,and the nonabelian omni-Lie algebroid is a matched pair of Leibniz algebroids.

Complete sequence of chloroplast genome from Sargassum vachellianum(Sargassaceae,Phaeophyceae):Genome structure and comparative analysis

Sargassum vachellianum is an ecologically important brown alga.It is China-specific and mainly inhabits in rocky intertidal zones in southeast coastal waters of China.In this study,we sequenced its circular complete chloroplast genome(cpDNA)and compared it with cpDNAs from S.vachellianum,S.horneri and S.thunbergii.The complete S.vachellianum cpDNA was 124,582 bp in length and consisted of a pair of inverted repeats(IRs)of 5435 bp,a large single copy(LSC)region of 73,721 bp and a small single copy(SSC)region of 39,991 bp.Totally 160 genes were predicted,including 132 protein-coding genes,four ribosomal RNA genes and 24 tRNA genes,and the coding sequences contributed 77.48%of the whole genome.In addition,25 SSR loci and 28 highly variable regions were identified from the S.vachellianum cpDNA,which might be used as candidates for developing DNA barcode markers of Sargassum species.The phylogenetic tree based on datasets of all the plastid-encoded proteins demonstrated that species of S.subgenus Bactrophycus were firstly combined and then clustered with S.vachellianum,which belongs to S.subgen.Sargassum.The results indicate that the chloroplast genomes are good resources for developing new DNA markers for taxonomy,and also as tools for evolutionary research of closely related species in future studies.

Transcriptome analysis of gill from Lateolabrax maculatus and aqp3 gene expression

The Lateolabrax maculatus is an important marine fish in China that can adapt to a wide range of water salinities.The gill is the main organ involved in fish osmoregulation and in this study,a cDNA library of the L.maculatus gill was constructed to understand gill function in Lateolabrax maculatus and it adaptation to salinity.A total raw data of 5.3G base pairs was obtained,followed removal of low-quality and linker DNA sequences and it yielded a total of 23,038,590 clean reads.After splicing and clustering,31,976 unigenes were obtained.The average transcript length was 1327 bp and N50 was 2057 bp.In comparisons with other tissues analysis of the gill transcriptome revealed a high level of relative expression of apolipoprotein E,CD74,keratin,type I cytoskeleton 13,carbonic anhydrase,betaine-homocysteine S-methyltransferase,and aquaporin 3(AQP3)genes.The L.maculatus aqp3(Lm-aqp3)gene was specific for the gills Lm-aqp3 and this gene has a typical transmembrane structure of six alpha helices and a water channel domain.Phylogenetic analysis indicated that Lm-aqp3 clusters with the homologue genes from Labrus bergylta and Dicentrarchus labrax.Quantitative RT-PCR confirmed that Lm-aqp3 was highly abundant in the gills and low expressed in other tissues(stomach,liver,brain,spleen and testis).Analysis of Lm-aqp3 in freshwater aquaculture fish revealed that gene expression was significantly statistical higher than in seawater(20 ppt)fish,suggesting that Lm-aqp3 may play an important role in water metabolism and osmotic pressure regulation in L.maculatus.

Higher order Dirac structure and Nambu-Poisson geometry

This paper studies the properties of Nambu-Poisson geometry from the(n-l,k)-Dirac structure on a smooth manifold M.Firstly,we examine the automorphism group and infinitesimal on higher order Courant algebroid,to prove the integrability of infinitesimal Courant automorphism.Under the transversal smooth morphismΦ:N-→M and anchor mapping of M on(n-1,k)-Dirac structure,it's holds that the pullback(n-1,k)-Dirac structure on M turns out an(n-1,k)-Dirac structure on N.Then,given that the graph of Nambu-Poisson structure takes the form of(n-1,n-2)-Dirac structure,it follows that the single parameter variety of Nambu-Poisson structure is related to one variety closed n-symplectic form under gauge transformation.WhenΦ:N-→M is taken as the immersion mapping of(n-1)-cosymplectic submanifold,the pullback Nambu-Poisson structure on M turns out the Nambu-Poisson structure on N.Finally,we discuss the(n-1,O)-Dirac structure on M can be integrated into a problem of(n-1)-presymplectic groupoid.Under the mapping II:M-→M/H,the corresponding(n-1,O)-Dirac structure is F and E respectively.If E can be integrated into(n-1)-presymplectic groupoid(g,2),then there exists the only,such that the corresponding integral of F is(n-1)-presymplectic groupoid(g,).