Yi chuan xue bao = Acta genetica Sinica最新文献

In this study, the aroA-M12 gene encoding bacterial 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) and the Btslm recombinant gene encoding Bacillus thuringiensis (Bt) toxin gene were introduced into a Brassica napus variety, Xiangyou No. 15, via Agrobacterium-mediated transformation using glyphosate as a selectable agent. PCR amplification and Southern blot analyses of T0 transgenic plants showed that the alien genes were transferred and integrated stably into the genome of Xiangyou No. 15. Western blot further confirmed that the alien genes were expressed in these plants. Transgenic plants with tolerance to both glyphosate and the tested pest were demonstrated by bioassays. Our result also clearly shows that the aroA-M12 gene can be used as an efficient selectable marker gene instead of antibiotic resistant markers in plant transformation.

A case-control study was carried out on a sample of 583 cases vs. 372 controls in the Chinese Han population, investigating several published polymorphisms in the YWHAH and NPY genes, which reported to be associated with schizophrenia. The polymorphism -134 (GCCTGCA)2-4, in the YWHAH was not analyzed for the failure of amplification, and the polymorphism T1128C in the NPY is not existent in the samples. The analysis was then emphasized on the variants -485C > T(NPY) and G753A(YWHAH). However, no significant differences of allele frequencies (with P values of 0.696 and 0.743, OR values of 1.041 and 0.962 respectively) or genotype frequencies (with P value of 0.45 and 0.75, chi2 = 1.51 and 0.58 respectively) among the matched groups were found. No sex-dependent effect was found either. Also,the analysis of the relative risk between the genotypes of the two genes indicates that the two genes could not cooperate with each other to add the risk of disease (P > 0.05). The results suggest that the polymorphisms - 485C > T (NPY) and G753A (YWHAH) are unlikely to be linked with genetic susceptibility to schizophrenia in the Chinese Han population.

To study the effect of RAB5A gene on microfilaments in human lung adenocarcinoma cells, AGZY83-a cells were stained with fluorescein isothiocyanate (FITC)-phalloidin. Microfilament bundles in RAB5A gene over-expressed AGZY83-a cells were shown to be denser than in control cells using confocal laser scanning microscope (CLSM). According to the analysis of Tumor Metastasis Microarray on RAB5A gene, three genes related to the regulation of cytoskeleton were identified, including NM23H1, Rac1 (downregulated in RAB5A over expressing cells), and S100A4 (upregulated in RAB5A overexpressing cells). Previous studies demonstrated that S100A4 gene functioned to suppress the expression of NM23H1 gene. To test if this elevated expression of S100A4 results in the down-regulation of NM23H1, RNAi was applied to silence the expression of S100A4 in AGZY83-a cells. Our data indicated that expression of NM23H1 was increased following the inhibition of S100A4 expression. Altogether, the results indicated that RAB5A gene was involved in the suppression of expression of NM23H1 by promoting the expression of S100A4.

The GP5 gene of porcine reproductive and respiratory syndrome virus (PRRSV) was integrated into the TK gene locus of pseudorabies virus (PRV) vaccine strain Bartha-K61, resulting in a TK- and gE- negative recombinant PRV harboring GP5 gene, designated as rPRV-GP5. The in vitro expression of the GP5 by rPRV-GP5-infected cells was analyzed by single-step growth analysis,Western blot,and indirect immunofluorescence test. It was shown that GP5 gene can be expressed authentically in the cytoplasm of rPRV-GP5-infected cells. Compared to its parental virus, rPRV-GP5 showed no obvious difference regarding viral replication and cytopathogenic effects in several cell cultures. Four PRV-negative sheep immunized intramuscularly with 10(6.0) PFU of rPRV-GP5 were fully protected from challenge with 10(3) LD50 of highly virulent PRV S strain of porcine origin. Ten PRV- and PRRSV-negative piglets given intranasally with 10(7.0) PFU of rPRV-GP5 and challenged intranasally with 10(5.0) TCID50 of virulent PRRSV CH-1a strain at day 63 post-inoculation developed antibodies against PRRSV 3, 5, 14 days post-challenge, as revealed by indirect immunofluorescence test, enzyme-linked immunosorbent assay and virus neutralization test. The results suggest that rPRV-GP5 is capable of inducing anamnestic immune response to PRRS in inoculated animals.

A sequence-specific M1GS ribozyme (M1-T3) was constructed by covalently linking an oligonucleotide (guide sequence,GS) to the 3' terminus of M1 RNA ,the catalytic subunit of RNase P from Escherichia coli. The engineered ribozyme is targeted to the mRNA sequence encoding a protein kinase (UL97) of HCMV and could effectively cleave the mRNA segment in vitro. Further studies about the significance of some structural elements in the M1 GS (e.g. the 3' CCA tail sequence and a bridge sequence between the 3' terminus of M1 RNA and the 5' terminus of the GS) were carried out. The results showed that the bridge sequence of 88 nucleotides in a mutated M1 GS (i.e. M1-T3*) dramatically increased the cleavage activity to the substrate in vitro. Moreover, the 3'CCA tail sequence was confirmed to be a necessary element for the cleavage activity of M1 GS ribozyme. These data we got in the study will help in understanding the interaction between the M1 GS RNA and its substrate,and will markedly facilitate the research of a general gene targeting agent for anti-HCMV applications.

Streptomyces sp. 139 was identified to produce a new exopolysaccharide Ebosin (139A) with antirheumatic arthritis activity in vivo. The Ebosin biosynthesis gene cluster(31.3 kb; GenBank Accession Number: AY131229) containing 22 ORFs (ste1-ste22) of Streptomyces sp. 139 had been reported previously. In this paper,we present experimental evidence for the identity of the ste6 gene product as a UDP-glucose dehydrogenase (UDPGDH). With pET-30a as vector,the gene was cloned and expressed in Escherichia coli BL21 (DE3). The expressed protein was purified to homogeneity by His-Bind resin affinity chromatograpy and it was able to catalyze UDP-glucose to UDP-glucuronic acid. To evaluate the function of ste6, the gene was disrupted by a single-crossover homologous recombination event and the result showed that ste6 is required in Ebosin biosynthesis.

Ferrous iron toxicity is the main factor limiting the productivity of rice in gleyic paddy soils. In this study, an F2 and an equivalent F3 populations derived from a japonica/indica cross of rice, Longza8503/IR64, were raised under iron-enriched solution cultures, and used to map QTLs controlling ferrous iron toxicity tolerance. A genetic linkage map consisting of 101 SSR markers was constructed to determine the position and nature of quantitative trait loci (QTLs) affecting Fe2+ toxicity tolerance. Three characters, i.e., leaf bronzing index (LBI), plant height (PH) and maximum root length (MRL) were evaluated for the F2 plants and F3 lines and the parents at the seedling stage in nutrient solution. A total of 20 QTLs for LBI, PH and MRL under the Fe2+ stress were detected over 10 of the 12 rice chromosomes, reflecting multigenic control of these traits. QTLs controlling LBI were located at the region of RM315-RM212 on chromosome 1, RM6-RM240 on chromosome 2 and RM252-RM451 on chromosome 4. Compared with other mapping results: (1) the QTL for LBI located at the region of RM252-RM451 on chromosome 4 was identical with the QTL for decreased chlorophyll content on a rice function map. Another QTL for LBI located at the region of RM315-RM212 on chromosome 1 was linked with the QTL for chlorophyll content which located at the region of C178-R2635 on a rice function map. (2) The third QTL for LBI located at the region of RM6-RM240 on choromosome 2 was linked with the QTL for potassium uptake located at the region of RZ58-CDO686 under potassium deficiency stress.

Bone size is an important risk factor, independent of bone mineral density (BMD), for osteoporotic fracture. Bone size has a high heritability. A better understanding of genetic factors regulating bone size will have important clinical implications. In this study, we explored the relationship between the alpha2-HS glycoprotein (AHSG) gene and bone size variation at the spine and hip in a Chinese population. The study sample comprised 1 260 subjects from 401 Chinese nuclear families (each including both parents and at least one female child). The Sac / polymorphism inside the exon 7 of the AHSG gene was genotyped and analyzed. This variant represents a nucleotide substitution of C to G at amino acid position 238 resulting in a translation polymorphism of threonine to serine and thus making a potential impact on gene function. We assessed population stratification but did not find significant evidence at any skeletal sites. We found significant association between the AHSG Sac / polymorphism and bone size at the intertrochanteric region (P = 0.019) and the total hip (P = 0.035). The polymorphisms explained 3.74% and 3.16% variations in bone size at the intertrochanteric region and total hip respectively. No significant evidence of linkage was detected, largely due to the limited number of sibpairs in this data set and less informative marker (AHSG Sac / polymorphism) (compared with microsatellite markers) for linkage analysis. Our results suggested that the AHSG gene may contribute to bone size variation at the hip in this Chinese population.

A MADS box gene HoMADS2 was cloned from Hyacinthus orientalis L. in this study. Sequence comparison revealed that HoMADS2 was highly homologous to the class B MADS box genes. Furthermore, phylogenetic analysis showed that HoMADS2 was closely related to PI gene family and this was also supported by the presence of specific diagnostic sites of PI homologs in K box domain and C terminal region,suggesting that HoMADS2 might be a PI-like gene. HoMADS2 mRNA was accumulated in all floral organs,different from the expression patterns of PI homologs in dicots. During in vitro flower development, HoMADS2 expression was constitutively expressed and not affected by the presence of cytokinin and auxin in the regenerated flowers. Our results indicated that the expression of HoMADS2 is different from those of both HAG1 and HoMADS1 in responding to plant hormones during in vitro flower development.

Streptomycetes are Gram-positive, soil-inhabiting bacteria of Actinomycetales. These organisms exhibit complex life cycle and secondary metabolic pathways, and produce many economically important secondary metabolites. This review presented recent progress in Streptomycetes chromosome structure,genomics and the research of secondary metabolic pathway in Streptomyces. As more genomic sequences become available, it wiil be greatly facilitated to elucidate metabolic and regulatory networks and gain the over-production of desired metabolites or create the novel production of commercially important compounds.