Analyses of gene effects and inheritance of resistance to bacterial blight in rice

We analyzed the resistant inheritance of ajaponica variety,Jia23,to two bacterial blightpathogen strains,KS-6-6 and Zhe 173,rep-resenting respectively the two predominantpathogenic types(Ⅱ and Ⅳ)in the rice crop-ping area along the Yangtze River Valley.Jia23 was crossed with susceptible vari-eties,Ewan8 and 7416.Fplants were back-

EFFECTS OF PSEUDOFYPE RETROVIRUS CONTAINING HUMAN N-RAS ANTISENSE GENE ON THE GROWTH OF HUMAN LIVER CANCER LTNM4 TRANSPLANTED IN NUDE MICE

An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC PRF/5 in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These results in vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer.

Anti-tumor effects induced by gene vaccines co-expressing truncated human prostate specific membrane antigen gene and mouse 4-1BBL

Objective To investigate the influence of m4-1BBL on anti-tumor effects induced by truncated human prostate specific membrane antigen ( tPSMA ) gene in mice. Methods A eukaryotic expression plasmid encoding tPSMA and m4-1BBL ( pDC316-tPSMA-IRES m4-1BBL) ,pDC316-tPSMA and pDC316 were constructed.

Genetic expression and effects of the rolled leaf gene Rl(t) in hybrid rice (Oryza sativa L.)

We constructed a nearisogenic line of rolled leaf gene Rl(t), which ex-pressed incompletely dondnance for the character of rolled leaf(RL), with ge-netic background of Zhenshan 97B. Using RL Zhenshan 97B and the originalZhenshan 97B as the female parents, and Minghui 63 and Yanhui 559 as themale parents, crosses of RL Shanyu 63 (RS63) and Shanyu 63(S63), RLShanyou 559 (RS559) and Shanyou 559 (S559) were made. Inheritance andeffects of Rl(t) in hybrid rice were studied at the flowering and at the 20 d afterflowering, respectively. Results were as follow:

Molecular Tagging and Effect Analysis of a New Small Grain Dwarf Gene in Rice

Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research.

Effect of apolipoprotein E gene Hha Ⅰ restricting fragment length polymorphism on serum lipids in cholecystolithiasis

AIM To investigate the role of apolipoprotein E (apoE) polymorphism in the lithogenesis of gallstone and the hereditary pathogenesis of the disease.METHODS Polymerase chain reaction (PCR)was used to study apoE phenotypes and allelefrequencies in patients with gallstones and control, and the fasting serum lipids of subjectswere also measured by enzymatic methods.RESULTS The levels of triglyceride (TG) andvery low density lipoprotein cholesterol (VLDLC) were much higher in Ez/, patients than that inE,/, control. E,/, patients were accompanied withremarkably low levels of high density lipoproteincholesterol (HDLC) and its subforms. But in E,/#patients there were only slight changes in levelsof VLDLC and low density lipoprotein cholesterol (LDL--C).CONCLUSION Different apoE phenotype patientswith gallstones have different cheracteristics ofdyslipidemia and the average level of serum lipids in patients with gallstones are higher thansubjects without gallstones in the same apoEgene phenotype. EZ allele is possibly one of thedangerous factors in the lithogenesis of cholecystolithiasis.

Effect of Rolled Leaf Gene Rl_(t) on Grain Quality in Hybrid Rice

Effects of rolled leaf gene Rl（t） on grain quality characters of hybrid rice were analyzed by using three pairs of rolled leaf near-isogenic lines under two fertilizer treatments. Under normal fertilizer level （e.g. 450 kg urea per ha）, head rice rates and milled rice recovery of rolled leaf hybrids were significantly higher than those of corresponding non-rolled crosses, while the chalky rice rate and chalkiness were all lower. Of the RVA profiles, the peak viscosity, the hot paste viscosity and the breakdown viscosity of the rolled were all higher than those of the corresponding non-rolled ones to various degrees. Increasing fertilizer application for promoting panicle development increased the brown, milled and head rice rates except for Shanyou 63, furthermore, significant difference of head rice rates existed between the rolled leaf Shanyou 559 and Shanyou 559; while the peak viscosity, the hot paste viscosity and the breakdown viscosity all decreased to different levels; changes of values of other characters had no apparent regularity. It suggested that Rl（t） could improve rice quality under certain conditions.

Analysis of Gene Effect on Four Characters of Immature Embryo Culture in Maize

This study was to find the regularity in the hereditary variation for the main culturing characters of the immature embryo culture in maize. Two kinds of inbred-line, R18-599 （red） with very excellent embryo culturing capacity and R15 with very poor embryo culturing capacity, were used as P1 and P2 for obtaining six generations. By culturing immature embryos of the six generations, four culturing characters, namely embryonic callus induction efficiency, nonembryonic callus induction efficiency, cloning ability of the embryonic callus, and number of regenerating plants, were analyzed using the general mean analysis and generation joint analysis. Results showed that the embryonic callus induction efficiency accorded with two major additive-dominance-epistatic genes and polygene-mixed additive-dominance-epistatic inheritance model. The induction efficiency of the nonembryonic callus accorded with two major additive-dominance-epistatic genes. The number of regenerating plants accorded with one major gene and polygene-mixed additive-dominance inheritance model. The cloning ability of the embryo callus accorded with two major genes and polygene-mixed inheritance model, whereas the effect of epistatic gene on this character was identified results of the two methods, generation joint analysis may genetic information. to be different using the two methods. By comparison of the not only raise experimental precision but also provide more

Isolation, Identification and Earliness Effect Analysis of Rice Dominant Earliness Gene Ef-cd

Ef-cd gene is a dominant earliness gene located on the short arm of rice chromosome 3. In this paper, through continuous backcross, self-pollination and molecular marker assisted selection, individual Ef-cd gene was isolated and its nearly isogenic lines were constructed by using early-maturing indica line 6442S-7 as the donor parent, and by using latematuring indica line Minghui 63 （MH63）, Shuhui 881 （SH881） and Shuhui 527 （SH527） as the recurrent parents （genetic background）, respectively. Further, it was found out that Ef-cd gene could generally advance rice to head 11-14 d earlier. So, it was considered that Ef-cd gene played an important role in rapid developing early-maturing and super high-yielding rice varieties.

THE EFFECT OF db-cAMP ON THE GENE EXPRESSION OF CALMODULIN AND CYTOSKELETON IN THE TRANSFORMED CELLS

We have demonstrated that the distribution of microtubules (MT), mlcrofilaments (MF) and fibronectin (FN) were diminished, while the gene expression of the calmodulin and c- fos enhanced in the transformed C3H10T1/2 cells. After treatment with 1 mM db-cAMP for 1 hour and 2 hours, there was an early and repldly reduced in gene expression of Calmodulin and c-fos respectively. After db-cAMP treatment for 4 -5 days, the number of capping cells of ConA binding decreased significantly and the cell surface microvllll decreased as well. The growth of treated cells was inhibited markedly. By using 4F1 cDNA probe, which is preferentially expressed In G1 phase, we have found that the db- cAMP treated cells were accumulated at G1 phase. Of particular interest is the fact that the distribution of microtubules, mlcrofilaments and fibronectln were recovered after treatment with 1 mM db-cAMP for 6 days. It is suggested that the Inhibition of proliferation, alteration, of phenotype and reco- very of cytoskeleton is transformed cells after treatment with db-cAMP are related to the Inhibition of gene expression of Calmodulin.

Cloning and expression of human arresten gene and effect of its recombinant protein on endothelial cell proliferation

To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites of prokaryotic expression vector pRSET containing T7 promoter.The recombinant plasmid pRSETAN was subsequently transformed into the strain E.coli BL21(DE3),and the target gene was expressed under induction of IPTG.The expressed protein was extracted,purified by Ni 2+ chelation affinity chromatography and refoled.The effect of the recombinant protein on proliferation of human umbilical vein endothelial cells (HUVECs) was also analyzed with the MTT assay.Results Endonuclease digesting and DNA sequencing confirmed that the arresten gene was correctly inserted into the expression vector.The recombinant protein was hightly expressed in the form of inclusion body in the host bacteria after induction.SDS-PAGE analysis revealed that the recombinant protein with a molecular weight of 26×103 amounted to 27% of the total bacterial proteins.The purity of the expected protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could significantly suppress proliferation of human umbilical vein endothelia cells(HUVECs) induced by vascular endothelial growth factor(VEGF).Conclusion Human arresten gene was successfully cloned into the expression vector pRSET and expressed at high level in Escherichia coli.Purified and refolded arresten protein could effectively inhibit proliferation of vascular endothelia cells.2 refs.

Studies on the Heredity of the Traits Related to the Photoperiod-Sensitive Phenomenon Among the Temperate ×Tropical Crosses in Maize

The genetic study of characters concerning photoperiod sensitivity of the growth and development stages, plant and ear height was carried out from 5 temperate tropical combinations by using P1 , P2, F1, F2, BC1, BC2 generations mean analysis. The results showed that the square sums of additive, of dominance and of epistatic gene effects contributed to total genetic variance were 11. 3 -53. 6%, 36.0 -78. 6% and 5.5 -27.0% respectively for five traits of the insensitive×insensitive combination to photoperiod, which suggested dominance gene effect was the most important among various gene effects. In insensitive X sensitive combination to photoperiod, the square sums of additive gene effect with 66. 9 - 84. 5 %, of dominance gene effect with 11. 6 30. 7% and of epistatic gene effect with 1.4-5. 2% were found for five tested traits, which showed additive gene effect held a dominant position, and dominance and epistatic gene effects were reduced compared with insensitive×insensitive combination. The differences existed among different insensitive×sensitive combinations. The proportion of the genetic component among the insensitive×sensitive crossbreed offspring in the temperate zone had a certain dosage effect on fading photoperiod sensitivity reaction. The sensitivity of BC1 , with 25 % of the tropical genetic component, is extremely weak, but with high application value.

Effects of Chirality on Gene Delivery Efficiency of Polylysine

Chirality is a key factor in the biological activity of many biomolecules. Poly（L-lysine）（PLL）, a polypeptide synthesized from L-lysine, is one of the mostly used cationic polymers for gene delivery. The effect of chirality of polylysine（PL） on its gene delivery remains unknown. Herein, we prepared three polylysines（PLs） with the similar molecular weight but different backbone chiralities including poly（L-lysine）（PLL）, poly（D-lysine）（PDL） and poly（DL-lysine）（PDLL）. The side chains of each PL were modified with propylene oxide（PO） of different chiralities including（R）PO,（S）PO and（R,S）PO. These PL-POs with distinct chirality in main and side chains could condense p DNA into polyplexes. The polyplexes had approximately the same size, zeta potential and binding ability, but showed distinct gene transfection efficiency. We found that the PLs of L-configuration in the main chain had higher transfection efficiency than that of D or DL configuration due to their faster cellular uptake, while the side chain chirality had no effect on transfection efficiency.

Effects of quorum sensing autoinducer degradation gene on virulence and biofilm formation of Pseudomonas aeruginosa

The aiiA gene from Bacillus thuringiensis was cloned into the Pseudomonas/E. coli shuttle vector and transformed into Pseudomonas aeruginosa strain PAO1. Western blotting showed that the AiiA protein was expressed in PAO1. After induction by IPTG for 6 h and 18 h, expression of the aiiA gene in PAO1 completely degraded the quorum sensing autoinducers N-acylhomoserine lactones (AHLs): N-oxododecanoyl-L-homoserine lactone (OdDHL) and N-butyryl-L-homoserine lactone (BHL). The re- duced amount of AHLs in PAO1 was also correlated with decreased expression and production of several virulence factors such as elastase and pyocyanin. AiiA expression also influenced bacterial swarming motility. Most importantly, our studies indicated that aiiA played significant roles in P. aeruginosa biofilm formation and dispersion, as observed by the differences of the biofilm formation on liquid and solid surfaces, and biofilm structures under a scanning electron microscope.

Preliminary analysis of species sensitivity distribution based on gene expression effect

Species sensitivity analysis is one of the major techniques applied to derive water quality criteria. Presently, the toxicity data used for development of water quality criteria are mainly in the biological individual level. With the increase of ecotoxicogenomics toxicity data, it is worth studying whether the gene expression effect data can be used to derive water quality criteria. Taking cadmium, copper and zinc as examples, we analyzed the toxic effects of the three heavy metals by constructing the species sensitivity distribution curves on the basis of extensive toxicity data. The results showed that the rank of species sensitivity for the acute, chronic and gene expression effect toxicity data of cadmium is "chronic>gene>acute". Although the gene expression effect data of copper and zinc are insufficient, the trend of data sensitivity of zinc is similar to cadmium. However, the trend of species sensitivity of copper is different from that of cadmium and zinc with higher sensitivity of gene expression data. It suggested that though the existing data of gene expression effects are not sufficient enough, they have the potential to be used in the development of chronic water quality criteria. For application in the derivation of water quality criteria, illogical test concentration design and insufficient target genes are two main weaknesses in the study of gene expression effects.

Expression of Acyl-lipid 12-desaturase Gene in Prokaryotic and Eukaryotic Cells and Its Effect on Cold Stress Tolerance of Potato

We report the expression profile of acyl-lipid △12-desaturase （desA） gene from Synechocystis sp. PCC6803 and its effect on cell membrane lipid composition and cold tolerance in prokaryotic （Escherichia coil） and eukaryotic （Solanum tuberosum） cells. For this purpose, a hybrid of desA and reporter gene encoding thermostable lichenase （licBM3） was constructed and used to transform these cells. The expression of this hybrid gene was measured using qualitative （Petri dish test, electrophoregram and zymogram） and quantitative methods （spectrometry and gas liquid chromatography assays）. The maximum level of linoleic acid in the bacterial cells containing hybrid gene was 1.9% of total fatty acids. Cold stress tolerance assays using plant damage index and growth parameters showed that cold tolerance was enhanced in primary transgenic lines because of increased unsaturated fatty acid concentration in their lipids. The greatest content of 18：2 and 18：3 fatty acids in primary transgenic plants was observed for lines 2 （73%） and 3 （41%）. Finally, our results showed that desaturase could enhance tolerance to cold stress in potato, and desaturase and lichenase retain their functionality in the structure of the hybrid protein where the enzymatic activity of target gene product was higher than in the case of reporter lichenase gene absence in the construction.

GPS： a constraint-based gene position procurement in chromosome for solving large-scale multiobjective multiple knapsack problems

The multiple knapsack problem （MKP） forms a base for resolving many real-life problems. This has also been considered with multiple objectives in genetic algorithms （GAs） for proving its efficiency. GAs use self- adaptability to effectively solve complex problems with constraints, but in certain cases, self-adaptability fails by converging toward an infeasible region. This pitfall can be resolved by using different existing repairing techniques; however, this cannot assure convergence toward attaining the optimal solution. To overcome this issue, gene position-based suppression （GPS） has been modeled and embedded as a new phase in a classical GA. This phase works on the genes of a newly generated individual after the recombination phase to retain the solution vector within its feasible region and to im- prove the solution vector to attain the optimal solution. Genes holding the highest expressibility are reserved into a subset, as the best genes identified from the current individuals by re- placing the weaker genes from the subset. This subset is used by the next generated individual to improve the solution vec- tor and to retain the best genes of the individuals. Each gene＇s positional point and its genotype exposure for each region in an environment are used to fit the best unique genes. Further, suppression of expression in conflicting gene＇s relies on the requirement toward the level of exposure in the environment or in eliminating the duplicate genes from the environment.The MKP benchmark instances from the OR-library are taken for the experiment to test the new model. The outcome por- trays that GPS in a classical GA is superior in most of the cases compared to the other existing repairing techniques.

Zbed3 participates in the subcortical maternal complex and regulates the distribution of organelles

We previously identified a subcortical maternal complex （SCMC） that is essential for early embryogenesis and female fertility in mice. However, the molecular mechanism by which the SCMC affects female fertility remains largely uncharacterized. Here, we report that a novel maternal protein, zinc finger BED-type containing 3 （Zbed3）, participates in the SCMC. Depletion of maternal Zbed3 results in reduced fecundity of females, because of the impaired and delayed development in a proportion of mutant embryos. The loss of maternal Zbed3 results in asymmetric zygotic division and abnormal distributions of organeUes in the affected oocytes and zygotes, similar to the phenotypes observed in females with disrupted core SCMC genes. Further investiga- tion revealed that these phenotypes are associated with disrupted dynamics of microtubules and/or formation of cytoplasmic lat- tices （CPLs）. The stability and localization of Zbed3 depend on, but are not required for, the formation of the SCMC. Thus, our data suggest Zbed3 as one of downstream proteins mediating SCMC functions and provide further insights into the roles of the SCMC and CPLs in female fertility.