Increase in Salt Tolerance of <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> by <Emphasis Type="Italic">TaDi19</Emphasis>

The gene expression profile chip of salt-resistant wheat mutant RH8706-49 under salt stress was investigated. The overall length of the cDNA sequence of the probe was obtained using electronic cloning and RT-PCR. An unknown gene induced by salt was obtained, cloned, and named TaDi19 (Triticum aestivum drought-induced protein). No related report or research on the protein is available. qPCR analysis showed that gene expression was induced by many stresses, such as salt. Arabidopsis thaliana was genetically transferred using the overexpressing gene, which increased its salt tolerance. After salt stress, the transgenic plant demonstrated better physiological indicators (higher Ca²⁺ and lower Na⁺) than those of the wild-type plant. Results of non-invasive micro-test technology indicate that TaDi19-overexpressing A. thaliana significantly effluxed Na⁺ after salt treatment, whereas the wild-type plant influxed Na⁺. Chelating extracellular Ca²⁺ resulted in insignificant differences in salt tolerance between overexpressing and wild-type A. thaliana. Subcellular localization showed that the gene encoding protein was mainly located in the cell membrane and nucleus. TaDi19 was overexpressed in wild-type A. thaliana, and the transgenic lines were more salt-tolerant than the control A. thaliana. Thus, the wheat gene TaDi19 could increase the salt tolerance of A. thaliana.     

The Effects of Stress-Related Hormones on the Stress Resistance in <Emphasis Type="Italic">Drosophila melanogaster</Emphasis> Carrying Mutation in the <Emphasis Type="Italic">Dilp6</Emphasis> Gene

The heat stress resistance of Drosophila melanogaster females carrying a hypomorphic mutation of the DILP6 insulin-like protein gene (dilp6 ⁴¹ ) under a change in the level of stress-related hormones (juvenile hormone and octopamine) is studied. It is revealed that the dilp6 ⁴¹ mutation decreases the heat stress resistance of mature D. melanogaster females. An experimental decrease in the level of juvenile hormone is shown to restore the stress resistance of mutant females to the level of stress resistance observed in wild type Canton S females. These data suggest that the effects of the dilp6 ⁴¹ mutation on the stress resistance of females are mediated by an increased level of juvenile hormone. An experimental increase in the octopamine level that causes an increase in juvenile hormone level supports this hypothesis: the resistance to heat stress decreases in females of both lines and this decrease is more significant in mutant females than in the control line. Thus, it is established for the first time that the effect of the hypomorphic dilp6 gene mutation on the heat stress resistance of D. melanogaster females is mediated by juvenile hormone.     

Spontaneous recombinase activity of Cre–ERT2 in vivo

Inducible Cre–ERT recombinase technology is widely used for gene targeting studies. The second generation of inducible Cre–ERT recombinase, hemizygous B6.129S-Tg(UBC-cre/ERT2)1Ejb/J (hereafter abbreviated as Cre–ERT2), a fusion of a mutated estrogen receptor and Cre recombinase, was engineered to be more efficient and specific than the original Cre–ERT. The putative mechanism of selective Cre-mediated recombination is Cre sequestration in the cytoplasm in the basal state with translocation to the nucleus only in the presence of tamoxifen. We utilized both a reporter mouse (B6.129 (Cg)-Gt(ROSA)26Sor ^{tm4(ACTB-tdTomato,-EGFP)Luo} /J) and endothelin converting enzyme-1 floxed transgenic mouse line to evaluate Cre–ERT2 activity. We observed spontaneous Cre activity in both settings. Unintended Cre activity is a confounding factor that has a potentially large impact on data interpretation. Thus, it is important to consider background Cre activity in experimental design.     

Growth Response to Hormones by a New Rat Ovary Cell Line

SEVERAL endocrine cell lines established in recent years show a functional response to hormones in vitro¹ but, except for one mammary cell line², none of them exhibits the normal hormone requirement for growth in vivo. We have now isolated a rat ovarian cell line whose growth in vitro is markedly stimulated by bovine luteinizing hormone (LH-NIH-B7), a pituitary gonadotrophin and by dexamethasone, a synthetic glucocorticoid. This cell line provides the first permanent in vitro system for studying the growth stimulation of gonadal cells by hormones.     

Evaluation of microbial globin promoters for oxygen-limited processes using <Emphasis Type="Italic">Escherichia coli</Emphasis>

Oxygen-responsive promoters can be useful for synthetic biology applications, however, information on their characteristics is still limited. Here, we characterized a group of heterologous microaerobic globin promoters in Escherichia coli. Globin promoters from Bacillus subtilis, Campylobacter jejuni, Deinococcus radiodurans, Streptomyces coelicolor, Salmonella typhi and Vitreoscilla stercoraria were used to express the FMN-binding fluorescent protein (FbFP), which is a non-oxygen dependent marker. FbFP fluorescence was monitored online in cultures at maximum oxygen transfer capacities (OTR_max) of 7 and 11 mmol L^?1 h^?1. Different FbFP fluorescence intensities were observed and the OTR_max affected the induction level and specific fluorescence emission rate (the product of the specific fluorescence intensity multiplied by the specific growth rate) of all promoters. The promoter from S. typhi displayed the highest fluorescence emission yields (the quotient of the fluorescence intensity divided by the scattered light intensity at every time-point) and rate, and together with the promoters from D. radiodurans and S. coelicolor, the highest induction ratios. These results show the potential of diverse heterologous globin promoters for oxygen-limited processes using E. coli.     

The effects of polymorphisms in <Emphasis Type="Italic">growth hormone</Emphasis> and <Emphasis Type="Italic">growth hormone receptor</Emphasis> genes on production and reproduction traits in Aberdeen-Angus cattle (<Emphasis Type="Italic">Bos taurus</Emphasis> L., 1758)

The study was aimed to analyze the relation between individual genotypes and allelic variants of SNPs g.2141C>G of growth hormone gene, g.914T>A and g.257A>G of growth hormone receptor gene with growth and reproduction traits and to evaluate the populationgenetic structure in Aberdeen-Angus cattle (Bos taurus L., 1758) sample of Eastern Ukraine according SNPs studied. Allele C of SNP g.2141C>G has a positive correlation with birth weight, body stature, bigger rump, udder and total exterior evaluation score, shorter calving interval and better calve birth weight and negative correlation with calve average daily gain. Allele T of SNP g.914T>A has positive correlation with the muscle and udder size; live weight in each age, average daily gain, weight and average daily gain of calves born conform to the principle AA>TT≥TA. SNP g.257A>G showed a positive correlation for G allele with muscle size. The population is in equilibrium for SNPs g.2141C>G and g.257A>G, and in disequilibrium for SNP g.914T>A. The analysis showed no linkage disequilibrium between SNPs g.914T>A and g.257A>G. Inbreeding coefficient F_ST in Aberdeen-Angus group studied was 16.1%.     

Effects of α- and β-Ecdysone on <Emphasis Type="Italic">in vitro</Emphasis> Diploid Cell Multiplication in <Emphasis Type="Italic">Drosophila melanogaster</Emphasis>

THE moulting hormone of insects is sometimes referred to as a growth and differentiation hormone. The steroid ecdysone and ecdysone analogues were shown to promote differentiation both in vivo and in vitro^1–3 but their action on cell multiplication is not certain^4–10. I used a diploid cell line, established from Drosophila melanogaster embryos by Echalier and Ohanessian^11,12, to assay insect hormones.     

Is It Possible to Manipulate Scelionidae Wasps’ Preference to a Target Host?

Parasitoid host selection is mainly mediated by chemical cues, which can be adjusted by experience, changing their innate behavior. Therefore, this study evaluated if immature experience (pre-imaginal conditioning) on eggs and volatiles from different host eggs has influence on parasitism and chemotaxic behavior of Telenomus podisi Ashmead and/or Trissolcus basalis Wollaston (Hymenoptera: Scelionidae). Both wasp species were submitted to a multiple-choice parasitism test among Euschistus heros (Fabricius), Piezodorus guildinii (Westwood), and Nezara viridula L. (Hemiptera: Pentatomidae) (Hemiptera: Pentatomidae) egg masses. Eggs from these three stink bugs were equally offered to female parasitoids. After that, adults which emerged from each host were also exposed to parasitism in a multiple-choice test for up to an additional generation. Moreover, in olfactometer “Y,” the behavior of innate and experienced T. podisi females to volatiles from hosts’ egg extracts was tested, to study their learning and memory ability. The original host had influence on T. podisi parasitism; however, T. basalis always parasitized more N. viridula eggs independently of its last rearing host. Innate T. podisi females responded positively to E. heros and P. guildinii egg volatiles, but this behavior was not observed in N. viridula. When T. podisi females were experienced on egg volatiles from a new host, they showed significant learning and memory ability for the specific host volatile for, at least, 24 h. Experienced wasps responded positively to N. viridula and through this result we have evidences about the possibility to manipulate wasp’s preferences to a specific target host.     

Identification of calmodulin binding proteins in the entomopathogenic fungus <Emphasis Type="Italic">Beauveria bassiana</Emphasis>

Calmodulin (CaM) is a primary Ca²⁺ receptor and plays a pivotal role in a variety of cellular responses in eukaryotes. Even though a large number of CaM-binding proteins are well known in yeast, plants, and animals, little is known regarding CaM-targeted proteins in filamentous fungi. To identify CaM-binding proteins in filamentous fungi, we used a proteomics method coupled with co-immunoprecipitation (CoIP) and MALDI-TOF/TOF mass spectrometry (MS) in Beauveria bassiana. Through this method, we identified ten CaM-binding proteins in B. bassiana. One of the CaM-targeted proteins was the heat shock protein 70 (BbHSP70) in B. bassiana. Our biochemical study showed that ATP inhibits the molecular interaction between BbHSP70 and CaM, suggesting a regulatory mechanism between CaM and ATP for regulating BbHSP70.     

Identification and Functional Analysis of Two Cotton Orthologs of <Emphasis Type="Italic">MAX2</Emphasis> Which Control Shoot Lateral Branching

Cotton (Gossypium spp.), as the most important fiber and oilseed crop in the world, is extremely important for the industry. However, due to its indeterminate growth habit and complex branching system, massive labor costs are needed for shoot apex removal and branch pruning during cotton production. Therefore, it is very important to explore branch-controlling genes and genetically modify the branch architecture of cotton. Strigolactones (SLs) are a novel class of plant hormone that inhibit the outgrowth of lateral branches. To elucidate the role of SLs in branch development of cotton, we cloned and characterized GhMAX2a and GhMAX2b from tetraploid upland cotton (Gossypium hirsutum), the orthologs of Arabidopsis MAX2, rice D3, and petunia RMS4. GhMAX2a/2b was ubiquitously expressed in all tested tissues of cotton, with relatively higher expression levels in leaves and lateral buds. Subcellular localization assay showed that the GhMAX2-GFP fusion protein localized to the nucleus. Both GhMAX2a and GhMAX2b can fully rescue the dwarfed and highly branched phenotypes of the Arabidopsis max2-1 mutant, indicating that GhMAX2s have conserved functions with that of AtMAX2. The cotton GhMAX2b interacted with Arabidopsis Skp1-like 1 (ASK1) proteins in vitro which was further confirmed in the Arabidopsis protoplasts using the co-immunoprecipitation assay, indicating that GhMAX2b probably functions through forming an SCF E3 complex with Skp and other proteins in the Arabidopsis. These results suggest that the cotton GhMAX2s encode functional MAX2 that can inhibit the shoot lateral branching. Further functional analysis of GhMAX2s in determining cotton branch architecture and yield is underway.     

On the minimum electron transport coefficients in tokamaks in the range of low collision frequencies

There are two close empirical scalings, namely, the T-11 and neo-Alcator ones, that provide correct estimates for the energy confinement time in tokamaks in ohmic heating regimes in the linear part of the dependence τ _E (\(\bar n_e \)) in the range of low values of \(\bar n_e \) and 〈ν _e ^* 〉 ≤ 1. The similar character of electron energy confinement in this range, which expands with increasing magnetic field B ₀, has stimulated the search for dimensionless parameters and simple physical models that would explain the experimentally observed dependences χ _e ～ 1/n _e and τ _Ee ～ \(\bar n_e \). In 1987, T. Okhawa showed that the experimental data were satisfactorily described by the formula χ_e⊥ = (c ²/ω _pe ² )ν _e /qR, in deriving of which the random spatial leap along the radius r on the electron trajectory was assumed to be the same as that in the coefficient of the poloidal field diffusion, while the repetition rate of these leaps was assumed to be ν _e /qR. In 2004, J. Callen took into account the decrease in the fraction of transient electrons with increasing toroidal ratio ? = r/R and corrected the coefficient c ²/ω _pe ² in Okhawa equation by the factor σ _‖ ^Sp /σ _‖ ^neo . If one takes into account this correction and assumes that the frequency of the stochastic process is equal to the reciprocal of the half-period of rotation of a trapped electron along its banana trajectory, then the resulting expression for χ_e⊥ will coincide with the T-11 scaling: χ _e ^an ∞ ?^1.75(T _e /A _i )^0.5/(n _e qR) at A i = 1. If the same stochastic process also involves ions, it may result in the opening of the orbit of a trapped ion at the distance ～(c/ω _pe )(m _i /m _e )^1/4. In this case, the calculated coefficient of electron and ion diffusion D is close to D ^an ≈ χ _e ^an /2.     

Check of Gene Number during the Process of rDNA Magnification

THE multiple sequences of rDNA (DNA complementary to ribosomal RNA) of the Drosophila genome are localized at the bobbed locus, located in the X chromosome, position 66 and in the short arm of the Y chromosome^1,2. Wild bobbed (bb⁺) is that locus which, without a partner, gives rise to a normal phenotype. That locus which in similar conditions is incapable of giving rise to a normal phenotype is called a bobbed mutation (bb) and contains fewer genes for rRNA. The number of genes for rRNA in different individuals can vary considerably. One mechanism for rDNA variation is unequal crossing over³. Another mechanism, described by Tartof⁴, becomes apparent when individual flies, carrying only one bobbed locus, are constructed and only if such a locus is on the X chromosome; that is, if one constructs Xbb⁺/O males (and also Xbb/O males) or Xbb⁺/X_NO- females. Such individuals show a higher rDNA content than expected from the analysis of the same locus in Xbb⁺/Xbb⁺ females or in Xbb⁺/Ybb⁺ males. The increase of rDNA in this case is not inheritable⁴.