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21.
Background
Domesticated einkorn (Triticum monococcum L.) is one of the oldest cultivated cereal crops in the world. Its small genome size (~?5.7 GB), low ploidy (2n?=?2x?=?14, AmAm) and high genetic polymorphism make this species very attractive for use as a diploid model for understanding the genomics and proteomics of Triticeae. Einkorn, however, is still a recalcitrant monocotyledonous species for the application of modern biotechnologies, including transgenesis. This paper reports the factors that may influence transgene delivery, integration, expression and inheritance in einkorn.Results
In this study, we report the successful genetic transformation of einkorn using biolistic-mediated DNA delivery. Immature embryo-derived tissues of spring einkorn were bombarded with a plasmid containing the reporter gene GFP (green fluorescent protein) driven by the rice actin promoter (act1) and the selectable bar gene (bialaphos resistance gene) driven by the maize ubiquitin promoter (ubi1). Adjustments to various parameters such as gas pressure, microcarrier size and developmental stage of target tissue were essential for successful transient and stable transformation. Bombarded einkorn tissues are recalcitrant to regenerating plants, but certain modifications of the culture medium have been shown to increase the production of transgenic events. In various experiments, independent transgenic plants were produced at frequencies ranging from 0.0 to 0.6%. Molecular analysis, marker gene expression and herbicide treatment demonstrated that gfp/bar genes were stably integrated into the einkorn genome and successfully inherited over several generations. The transgenes, as dominant loci, segregated in both Mendelian and non-Mendelian fashion due to multiple insertions. Fertile homozygous T1-T2 populations of transgenic einkorn that are resistant to herbicides were selected.Conclusion
To the best of our knowledge, this is the first report of the production of genetically modified einkorn plants. We believe that the results of our research could be a starting point for the application of the current biotechnological-based technologies, such as transgenesis and genome editing, to accelerate comparative functional genomics in einkorn and other cereals.22.
Inna?Chaban Marat?Khaliluev Ekaterina?Baranova Neonila?Kononenko Sergey?Dolgov Elena?SmirnovaEmail author 《Protoplasma》2018,255(6):1597-1611
Parthenocarpy and fruit malformations are common among independent transgenic tomato lines, expressing genes encoding different pathogenesis-related (PR) protein and antimicrobal peptides. Abnormal phenotype developed independently of the expression and type of target genes, but distinctive features during flower and fruit development were detected in each transgenic line. We analyzed the morphology, anatomy, and cytoembryology of abnormal flowers and fruits from these transgenic tomato lines and compared them with flowers and fruits of wild tomatoes, line YaLF used for transformation, and transgenic plants with normal phenotype. We confirmed that the main cause of abnormal flower and fruit development was the alterations of determinate growth of generative meristem. These alterations triggered different types of anomalous growth, affecting the number of growing ectopic shoots and formation of new flowers. Investigation of the ovule ontogenesis did not show anomalies in embryo sac development, but fertilization did not occur and embryo sac degenerated. Nevertheless, the ovule continued to differentiate due to proliferation of endothelium cells. The latter substituted embryo sac and formed pseudoembryonic tissue. This process imitated embryogenesis and stimulated ovary growth, leading to the development of parthenocarpic fruit. We demonstrated that failed fertilization occurred due to defective male gametophyte formation, which was manifested in blocked division of the nucleus in the microspore and arrest of vegetative and generative cell formation. Maturing pollen grains were overgrown microspores, not competent for fertilization but capable to induce proliferation of endothelium and development of parthenocarpic ovary. Thus, our study provided new data on the structural transformations of reproductive organs during development of parthenocarpic fruits in transgenic tomato. 相似文献
23.
Thomas GH; Newbern EC; Korte CC; Bales MA; Muse SV; Clark AG; Kiehart DP 《Molecular biology and evolution》1997,14(12):1285-1295
Many structural, signaling, and adhesion molecules contain tandemly
repeated amino acid motifs. The alpha-actinin/spectrin/dystrophin
superfamily of F-actin-crosslinking proteins contains an array of triple
alpha-helical motifs (spectrin repeats). We present here the complete
sequence of the novel beta-spectrin isoform beta(Heavy)- spectrin (beta H).
The sequence of beta H supports the origin of alpha- and beta-spectrins
from a common ancestor, and we present a novel model for the origin of the
spectrins from a homodimeric actin-crosslinking precursor. The pattern of
similarity between the spectrin repeat units indicates that they have
evolved by a series of nested, nonuniform duplications. Furthermore, the
spectrins and dystrophins clearly have common ancestry, yet the repeat unit
is of a different length in each family. Together, these observations
suggest a dynamic period of increase in repeat number accompanied by
homogenization within each array by concerted evolution. However, today,
there is greater similarity of homologous repeats between species than
there is across repeats within species, suggesting that concerted evolution
ceased some time before the arthropod/vertebrate split. We propose a
two-phase model for the evolution of the spectrin repeat arrays in which an
initial phase of concerted evolution is subsequently retarded as each new
protein becomes constrained to a specific length and the repeats diverge at
the DNA level. This evolutionary model has general applicability to the
origins of the many other proteins that have tandemly repeated motifs.
相似文献
24.
Comparisons of the molecular evolutionary process at rbcL and ndhF in the grass family (Poaceae) 总被引:2,自引:1,他引:1
We examine rate heterogeneity among evolutionary lineages of the grass
family at two plasmid loci, ndhF and rbcL, and we introduce a method to
determine whether patterns of rate heterogeneity are correlated between
loci. We show both that rates of synonymous evolution are heterogeneous
among grass lineages and that are heterogeneity is correlated between loci
at synonymous sites. At nonsynonymous sites, the pattern of rate
heterogeneity is not correlated between loci, primarily due to an aberrant
pattern of rate heterogeneity at nonsynonymous sites of rbcL. We compare
patterns of synonymous rate heterogeneity to predictors based on the
generation time effect and the speciation rate hypotheses. Although there
is some evidence for generation time effects, neither generation time
effects nor speciation rates appear to be sufficient to explain patterns of
rate heterogeneity in the grass plastid sequences.
相似文献
25.
A S Sa?dakhmetova O N Dolgov V V Sherstnev 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1986,(2):45-49
The intraventricular injection of brain specific S-100 proteins leads to the prolonged heterochronous changes of the inherent rat behaviour forms during the period of water and food needs restitution. The effects of various doses of S-100 proteins fractions on the behavioural activity differs in the degree of expression and in time of their onset. The specific influence of some S-100 proteins fractions on duration of the different inherent forms of rat behaviour can be explained by plurality of molecular mechanisms of their effects. 相似文献
26.
Iu P Nikitin M I Dushkin A V Dolgov I A Gordienko 《Biulleten' eksperimental'no? biologii i meditsiny》1986,102(8):162-164
Intraperitoneal injection of 25 micrograms/100 g body weight of 17 alpha-ethinyl estradiol to rats was shown to decrease serum cholesterol and to increase hepatic cholesterol. The rise in the level of non-labeled and C14-labeled free and esterified cholesterol in hepatic homogenate, as well as in lysosomal and cytosol fractions was accompanied by reduced activity of acyl-CoA-cholesterol acyltransferase and increased activity of lysosomal cholesterol esterase, as compared with the controls. The activity of cytoplasmic cholesterol esterase remained practically unchanged. Fistula bile of treated rats collected during 30 min was analyzed for the concentration of free cholesterol and bile acids. It has been shown that treatment of rats with 17 alpha-ethinyl estradiol caused an increase in hepatic cholesterol elimination via bile pathways. 相似文献
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Plasma Physics Reports - In this paper we present experimental data on the generation of ions with MeV-energy in a Z-pinch discharge in a heavy-element medium. The calculations show that the escape... 相似文献