Genetic diversity of threeAristichthys nobilis populations and one inbreeding stock

Genetic diversity of threeAristichthys nobilis populations and one inbreeding stock was studied using random amplified polymorphic DNA (RAPD) method. Materials of natural populations were collected from two counties of Guangxi Province, Hengxian (NH) and Shanglin (NS) and one city of Hubei Province, Wuhan city. (NW). Shanglin and Hengxian's river system respectively belongs to Qianjiang and Yujiang River, two tributaries confluencing to Xunjiang River, main tributary of Xijiang River, which is the biggest tributary of the Zhujiang River system, and Wuhan's water system belongs to the Yangtse River system. The inbreeding stock (RS) was the more than 10 generation descendant by brother-sister mating system whose parents were collected from Shanglin. The results showed that the genetic variety of individuals of RS was very low (0.105 4), whereas that of natural populations was relatively high, which from high to low was 0.158 1 (NW), 0.132 0 (NH) and 0.110 5 (NS). As an index for genetic distance pair-wise populations, the genetic variety between populations was studied, which characterized the genetic distance between populations. The genetic distance of NW and NH, NW and NS, NW and RS were respectively high, whereas that of NH and NS, NS and RS, NH and RS was low. Chi-test (χ ²) and the analysis of the genetic variety pair-wise populations was taken as efficient approach for studying population difference. Foundation item: Supported by the National Ninth-Five Research Program (No. 96-08010301), and Species Resource and Biotech of Freshwater Fish Pivot Laboratory of Agriculture Ministry Biography: Wang He(1978-), male, Master, research direction: molecular genetic markers in fish     

贵州马铁菊头蝠群体遗传结构的微卫星分析

利用6对微卫星引物对贵州马铁菊头蝠的等位基因频率、基因杂合度和多态性信息含量进行了遗传检测。结果表明,6对微卫星引物共扩增出18个等位基因。基因频率分布在0.021 0～0.833 0之间。6个微卫星位点的平均杂合度为0.342 7,平均多态性信息含量为0.381 3。分析认为贵州马铁菊头蝠遗传多样性相对较低。     

Genetic diversity of rhizobial populations recovered from three Lotus species cultivated in the infra-arid Tunisian soils

Eighty-three bacterial strains isolated from root nodules of Lotus creticus, L. pusillus, and L. arabicus grown in infra-arid Tunisian soils were characterized using a polyphasic approach including phenotypic analysis, rep-PCR and PCR-RFLP analyses of the 16S rRNA gene. Phenotypically, all isolates are fast growers the majority of which grow at a pH of between 5.5 and 9. Most of the tested isolates tolerate NaCl concentrations from 1.39% to 3.48%. By rep-PCR fingerprinting, the genomic similarity varied from 30% to 98%. All tested isolates were clustered into 32 rep-PCR clusters at the similarity level of 80%. The genomic divergence of strains revealed by rep/PCR analysis appeared to be very important since a molecular polymorphism delimiting symbionts for each species of Lotus was identified. With the high-resolution of rep-PCR profiles of the isolates obtained using Pearson’s/UPGMA analysis, the isolates were resolved into 60 different profiling groups to undergo 16S ARDRA analyses. The analysis of all restriction fragments from each strain based on the UPGMA algorithm from the combined patterns showed that Lotus isolates are very diverse and that they were affiliated to Sinorhizobium, Rhizobium, and Mesorhizobium genera.     

Evolutionary mode of metallothioneins inferred from Cd-MT genes of Tetrahymena

FromTetrahymena thermophila (strain BF5), the coding region ofCd-MT gene was cloned and sequenced, and identified as MTTI isoform. A serial duplicate structure is discovered in its amino acid sequence, which separates the coding region into three parts (Part 1: 7–61: Part 2: 64–118; Part 3: 122–162). The alignments among them and comparison with the corresponding parts of MT1 isoform suggest that MT1 and MTT1 isoforms both come from the same ancient gene that is homologous to Part 1, and Cd-MTs ofTetrahymena are aroused by such ancient gene duplication. The prediction of secondary structures and the analysis of the disulfide-bonding state of cysteine show that there are a lot of differences between MT1 and MTT1 isoforms, which maybe relate to their function mechanism. Foundation item: Supported by KSCX of Chinese Academy of Sciences Grant (SW-102) and the Allocation from the Earmaarked Grant for Hong Kong. Biography: WAN Mingliang (1980-). male, Ph. D. candidate, research direction: molecular ecotoxicology of protozoan.     

The expression of vasa gene during zebrafish ( Danio rerio ) oogenesis

vasa gene expression pattern during oogenesis of zebrafish was examined usingin situ hybridization and fluorescent quantitative RT-PCR. During zebrafish oogensis,vasa mRNA is expressed strongly and uniformly distributed in the cytoplasm in stage II oocytes, followed by a distribution among vacuome in stage III. Later in stage IV and V,vasa mRNA is enriched at the cortex and finally localized at the cortex. The fluorescent quantitative RT-PCR shows that the quantity ofvasa mRNA decreases from stage II to stage III, but remains relatively invariable from stage III to stage V. The observed differences invasa mRNA expression in the different stages of zebrafish oogenesis suggest thatvasa gene plays an important role during oogenesis. Foundation item: Supported by the National Natural Science Foundation of China (30370744, 30150005) Biography: XIANG Fang (1979-), male, Master candidate, research direction: molecular development of animals.     

A laurent expansion and residue theorems of k -regular functions in clifford analysis

In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in 1 R ₁ ⁿ with values in R _0,n . We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems.      

Assessment of genetic diversity in the forest musk deer （Moschus berezovskii） using microsatellite and AFLP markers

Microsatellite genotyping and amplified fragment length polymorphism (AFLP) techniques are often utilized in studies of conservation genetics of endangered animals. To select a more effective marker system for conserving the endangered forest musk deer, we used microsatellite and AFLP markers to estimate levels of genetic diversity of two populations, the pure mother Jinfengshan (JFS) group and the offspring Baisha (BS) group with introduction of new blood. It was expected that JFS would pos- sess significa...     

Antioxidant Activity In Vitro of Three Constituents from Caesalpinia sappan L

Antioxidant activities of the 95% ethanol extract from Caesalpinia sappan heartwood （ECS）, protosappanin A, protosappanin B, and brazilein were studied in vitro. The inhibition of the formation of malondialdehyde （MDA） and the scavenging of superoxide anions, hydrogen peroxide, and hydroxyl radicals were assayed. The experimental results show that all four substances had antioxidant activity in vitro but their capabilities differed for the different indicators. ECS, protosappanin A, and protosappanin B show more inhibition of MDA and scavenging of hydrogen peroxide, while brazilein shows more scavenging of hydroxyl radicals. All the samples show little scavenging of superoxide anions.     

Efficient indica and japonica rice identification based on the InDel molecular method: Its implication in rice breeding and evolutionary research

An efficient molecular method for the accurate and efficient identification of indica and japonica rice was created based on the polymorphisms of insertion/deletion (InDel) DNA fragments obtained from the basic local alignment search tool (BLAST) to the entire genomic sequences of indica (93-11) and japonica rice (Nipponbare). The 45 InDel loci were validated experimentally by the polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) in 44 typical indica and japonica rice varieties, including 93-11 and Nipponbare. A neutrality test of the data matrix generated from electrophoretic banding patterns of various InDel loci indicated that 34 InDel loci were strongly associated with the differentiation of indica and japonica rice. More extensive analyses involving cultivated rice varieties from 11 Asian countries, and 12 wild Oryza species with various origins confirmed that indica and japonica characteristics could accurately be determined via calculating the average frequency of indica- or japonica-specific alleles on different InDel loci across the rice genome. This method was named as the “InDel molecular index” that combines molecular and statistical methods in determining the indica and japonica characteristics of rice varieties. Compared with the traditional methods based essentially on morphology, the InDel molecular index provides a very accurate, rapid, simple, and efficient method for identifying indica and japonica rice. In addition, the InDel index can be used to determine indica or japonica characteristics of wild Oryza species, which largely extends the utility of this method. The InDel molecular index provides a new tool for the effective selection of appropriate indica or japonica rice germplasm in rice breeding. It also offers a novel model for the study of the origin, evolution, and genetic differentiation of indica and japonica rice adapted to various environmental changes.     

A note on m -weights of linear codes

m-weight, as a new generalization of classical Hamming weight, was discussed in this paper. A condition for the existence of linear codes of certainm-weights was given; the Singleton bound, Plotkin bound and Sphere Parking bound of Hamming weight were correspondingly generalized to them-weight. Foundation item: Supported by the National Program on Basic Sciences (973 Program, G1999075102) Biography: YUAN Yuan (1979-), female, Ph. D candidate, research directions: combination and codes.     

Speciation of the genus Arthricocephalus Bergeron, 1899 (Trilobita) from the late Early Cambrian and its stratigraphic significance

The genus Arthricocephalus Bergeron, 1899 is revised, and Halipanktos Balker & Peel, 1997 is suggested here as a senior synonym. The subgenus Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al., 1974 is considered as a separate genus. Of the 20 previously assigned species of Arthricocephalus (Arthricocephalus) Bergeron, 1899, Arthricocephalus (Arthricocephalites) Chien & Lin in Lu et al., 1974, Arthricocephalus (Euarthricocephalus) Ju, 1983 are lumped into eight species. The speciation trend of Arthricocephalus and Arthricocephalites is demonstrated based on their stratigraphic occurrences. It not only enhances the resolution of the biostatigraphic zonation in the uppermost Lower Cambrian, but also represents a potential candidate to define the Duyunian stage. The base of the stage is suggested at the first appearance datum (FAD) of Arthricocephalus chauveaui Bergeron, 1899 within the evolutionary lineage from Ar. jiangkouensis Yin in Yin & Li,1978 to Ar. chauveaui in a global scale.     

Deviation inequality for the number of k -cycles in a random graph

We study the number of k-cycles in a random graph G(n, p). We estimate the probability that a random graph contains more k-cycles than expected. In this case, the usual martingale inequality with bounded difference is not effective. By constructing a variable that approximates to the number of k-cycles in a random graph and using a new and extensive martingale inequality, we get the results in this paper. Foundation item: Supported by the National Natural Science Foundation of China (10571139)     

Analysis of IGF2 mRNA expression and its methylation status between cattle yaks and their parents

Cattle yaks are an F1 hybrid between cattle and yaks and exhibit significant hybrid vigor. However, cattle yaks are sterile males. To study the epigenetic aspects of this reproductive isolation, IGF2 mRNA expression in cattle yaks and their parents and the patterns of the IGF2 differentially methylated regions (DMR) were examined in blood and testes. The results showed that IGF2 expression in cattle yaks’ testes was lower than in their parents (P < 0.01). The IGF2 DMR was highly methylated (above 90%) in blood and testes of cattle yaks, yaks and cattle, with the highest level in cattle yaks (P > 0.05). Our study showed that IGF2 plays an important role in bovine spermatogenesis and might be involved in cattle-yak male sterility. The methylation level of the IGF2 DMR was irrelevant to the lower expression of IGF2 in cattle yaks; other factors perhaps play roles in its expression.     

Identification of a bi-directional promoter from Tomato yellow leaf curl China virus

A bi-directional promoter of Tomato yellow leaf curl China virus (TYLCCNV) was obtained with the total DNA from TYLCCNV isolate Y10 infected tobacco leaves as a template. Plant expression vectors were constructed by fusing the amplified DNA fragment with the gus gene and nopaline terminator in different orientations. The vectors containing promoter fragments were transferred into leaf cells and plant stems of Nicotiana benthamiana by Agrobacterium-mediated method. Transient expression results showed that both the complementary and virion-sense promoters could drive the gus gene to express, and the GUS activity of the complementary-sense promoter was stronger than that of the virion-sense. Co-expression of the vector containing βC1 gene of TYLCCNV DNAβ with the vector containing a bi-directional promoter revealed that the βC1 protein has no impact on expression of either the virion- or the complementary-sense promoter.     

Cloning, Characterization, and Expression Analysis of Calreticulin from Pearl Oyster Pinctada fucata

Calreticulin is a unique calcium-binding protein with multiple functions mostly located in the sarcoplasmic/endoplasmic reticulum. A large amount of calcium is absorbed from the medium and transported to mineralization sites during biomineralization in pearl oyster. This paper describes the cloning of the full-length cDNA of calreticulin from Pinctada fucata, namely PCRT. PCRT encodes a deduced 414-amino acid protein, which includes a predicted 17- amino acid signal peptide and an endoplasmic reticulum retrieval sequence HDEL. The protein shows 63%-76% sequence identity and shares some common characteristics with calreticulins from other species. Semi-quantitative RT-PCR indicates that PCRT is ubiquitously expressed in all tissues tested with the highest expression in the hemolymph and the mantle. In situ hybridization analysis of PCRT in the mantle showed strong signals in the inner fold, the inner side of middle fold, and the inner side of outer fold of the mantle epithelium, All these results suggest PCRT might be involved in Ca^2＋ transport and storage during oyster biomineralization.     

H-ATPase in the plasma membrane of Arabidopsis pollen cells is involved in extracellular calmodulin-promoted pollen germination

In this paper, the role of the plasma membrane (PM) H⁺-ATPase in extracellular calmodulin (CaM)-promoted pollen germination and in tube growth of Arabidopsis thaliana was investigated. Pollen germination, pollen tube growth rate, free cytosolic Ca²⁺ concentration ([Ca²⁺]_cyt) and Ca²⁺ channel activity in the PM of pollen cells were measured. In response to fusicoccin or CaM treatment, in vitro pollen germination and pollen tube growth rate, [Ca²⁺]_cyt and activity of a hyperpolarization-activated Ca²⁺-permeable channel increased. Sodium vanadate inhibited the promotion of these parameters by extracellular CaM. The results suggest that H⁺-ATPase may be involved in extracellular CaM-regulated pollen germination and in tube growth by modulation of the hyperpolarization-activated Ca²⁺ channel in the PM of A. thaliana pollen cells.