37 research outputs found
Genome-wide data from medieval German Jews show that the Ashkenazi founder event pre-dated the 14th century
We report genome-wide data from 33 Ashkenazi Jews (AJ), dated to the 14th century, obtained following a salvage excavation at the medieval Jewish cemetery of Erfurt, Germany. The Erfurt individuals are genet-ically similar to modern AJ, but they show more variability in Eastern European-related ancestry than mod-ern AJ. A third of the Erfurt individuals carried a mitochondrial lineage common in modern AJ and eight carried pathogenic variants known to affect AJ today. These observations, together with high levels of runs of homozygosity, suggest that the Erfurt community had already experienced the major reduction in size that affected modern AJ. The Erfurt bottleneck was more severe, implying substructure in medieval AJ. Overall, our results suggest that the AJ founder event and the acquisition of the main sources of ancestry pre-dated the 14th century and highlight late medieval genetic heterogeneity no longer present in modern AJ.The study was funded by the Israel Science Foundation grant 407/17 and the United States-Israel Binational Science Foundation grant 2017024 to S.C., by the National Science Foundation (USA) grants 1912776 and 0922374 to V.R., by the MCIN/AEI/10.13039/501100011033 and by "ESF Investing in your future" grant "Ayudas para contratos Ramon y Cajal" to I.O., and by the following grants to D.R.: NIH grants GM100233 and HG012287; the Allen Discovery Center program, a Paul G. Allen Frontiers Group advised program of the Paul G. Allen Family Foundation; John Templeton Foundation grant 61220; a private gift from Jean-Francois Clin; and the Howard Hughes Medical Institute
Impact of scion/rootstock reciprocal effects on metabolomics of fruit juice and phloem sap in grafted Citrus reticulata.
BACKGROUND:Rootstock has a significant impact on plant growth and development, including fruit maturation. However, the existence of mutual interaction between scion and rootstock is often neglected. To explore the origin of different fruit quality traits in citrus, we studied the effect of rootstock and the reciprocal interaction between scion and rootstock of nine combinations; three mandarin varieties grafted on three different rootstocks. We analyzed the metabolic profile of juice via gas and liquid chromatography-mass spectrometry (GC-MS and LC-MS, respectively). Additionally, we profiled phloem sap composition in the scion and the rootstock. Quality traits of fruit and their physio-chemical characteristics were also evaluated. RESULTS:For all three cultivars, rootstock was found to affect fruit yield and biochemical fruit quality parameters (sugar and acidity) in interactions with the scions. In mandarin juice, eight of 48 compounds (two primary and six secondary) were related directly to the rootstock, and another seven (one primary and six secondary) were interactively affected by scion and rootstock. In scion and rootstock sap, six and 14 of 53 and 55 primary metabolites, respectively, were directly affected by the rootstock, while 42 and 33 were affected by rootstock interactively with scion, respectively. CONCLUSION:In this work, we show for the first time a reciprocal effect between rootstock and scion. Based on our results, the scion and rootstock interaction might be organ, distance or time dependent
Root-Associated Microbiomes, Growth and Health of Ornamental Geophytes Treated with Commercial Plant Growth-Promoting Products
The microbial community inhabiting a plant’s root zone plays a crucial role in plant health and protection. To assess the ability of commercial plant growth-promoting products to enhance the positive effects of this environment, two products containing beneficial soil bacteria and a product containing plant extracts were tested on Zantedeschia aethiopica and Ornithogalum dubium. The products were tested in two different growing media: a soil and a soilless medium. The effects of these products on Pectobacterium brasiliense, the causal agent of soft rot disease, were also evaluated in vitro, and on naturally occurring infections in the greenhouse. The growing medium was found to have the strongest effect on the microbial diversity of the root-associated microbiome, with the next-strongest effect due to plant type. These results demonstrate that either a single bacterial strain or a product will scarcely reach the level that is required to influence soil microbial communities. In addition, the microbes cultured from these products, could not directly inhibit Pectobacterium growth in vitro. We suggest density-based and functional analyses in the future, to study the specific interactions between plants, soil type, soil microbiota and relevant pathogens. This should increase the effectiveness of bio-supplements and soil disinfestation with natural products, leading to more sustainable, environmentally friendly solutions for the control of bacterial plant diseases
Novel expression vectors enabling induction of gene expression by small-interfering RNAs and microRNAs.
Small-interfering RNAs and microRNAs are small ∼21-22 nucleotide long RNAs capable of posttranscriptional suppression of gene expression. The synthetic siRNAs are especially designed to target pre-specified genes and are common molecular biology tools. The miRNAs are endogenous regulators of gene expression found in a wide variety of eukaryotes. miRNAs are currently utilized for diagnostics applications. Therapeutically, various miRNA-antagonizing tools are being explored and miRNAs are also utilized for cell-specific inhibition of the expression of gene therapy vectors harboring target sites for specific miRNAs. Here we show, for the first time, that siRNAs and miRNAs can be harnessed to induce gene expression. We designed special expression vectors in which target sites for artificial siRNAs or endogenous miRNAs are located between the transgene and an Upstream Inhibitory Region (UIR). We hypothesized that cleavage of the mRNA by siRNAs or miRNAs will separate the transgene from the UIR and the resulting uncapped mRNA will be capable of being translated. A UIR composed of seven open reading frames was found to be the most efficient inhibitor of the translation of the downstream transgene. We show that under such a configuration both artificial siRNAs and endogenous miRNAs were capable of inducing transgene expression. We show that using the diphtheria toxin A-chain gene, in combination with target sites for highly expressed miRNAs, specific induction of cell-death can be achieved, setting the stage for application to cancer therapy
Use of X-ray Mutagenesis to Increase Genetic Diversity of Zantedeschia aethiopica for Early Flowering, Improved Tolerance to Bacterial Soft Rot, and Higher Yield
The development of new cultivars is important for the profitability of the floriculture industry. There is a limited number of cultivars of Zantedeschia aethiopica, an iconic ornamental cut flower, garden plant, and potted plant, because of the incompatibility of interspecific crossings within the genus. Most present-day varieties are the result of spontaneous mutations or classical breeding within the species, followed by a long selection process. Here, Z. aethiopica mutants were generated by treating seeds with 100 Gy of X-ray radiation. The resulting putative mutants were selected based on particular flowering parameters and compared to nonirradiated, control plants. Over two growing seasons, characteristics such as early flowering, flower size and shape, yield, and response to soft-rot disease were monitored, and considerable variation was observed among the mutated lines. Out of 319 mutants, 20 lines were selected based on their phenotypes and then propagated and further analyzed. Within this group, only two phenotypes displayed at least five improved flowering properties under natural Mediterranean conditions. The rest displayed two to four desired combinations of flowering traits, some with great commercial potential
Sucrose Synthase and Fructokinase Are Required for Proper Meristematic and Vascular Development
Sucrose synthase (SuSy) and fructokinase (FRK) work together to control carbohydrate flux in sink tissues. SuSy cleaves sucrose into fructose and UDP-glucose; whereas FRK phosphorylates fructose. Previous results have shown that suppression of the SUS1,3&4 genes by SUS-RNAi alters auxin transport in the shoot apical meristems of tomato plants and affects cotyledons and leaf structure; whereas antisense suppression of FRK2 affects vascular development. To explore the joint developmental roles of SuSy and FRK, we crossed SUS-RNAi plants with FRK2-antisense plants to create double-mutant plants. The double-mutant plants exhibited novel phenotypes that were absent from the parent lines. About a third of the plants showed arrested shoot apical meristem around the transition to flowering and developed ectopic meristems. Use of the auxin reporter DR5::VENUS revealed a significantly reduced auxin response in the shoot apical meristems of the double-mutant, indicating that auxin levels were low. Altered inflorescence phyllotaxis and significant disorientation of vascular tissues were also observed. In addition, the fruits and the seeds of the double-mutant plants were very small and the seeds had very low germination rates. These results show that SUS1,3&4 and FRK2 enzymes are jointly essential for proper meristematic and vascular development, and for fruit and seed development
Decrease in cell viability by siRNA and miRNA dependent induction of DTA.
<p>U251 cells were transfected with the indicated construct (50 ng) with (A) or without (B) siRNAs (10pmol). Cell viability was determined by an XTT assay. The XTT viability value of the “No DTA” construct was set as 100% and the viability value obtained for all other constructs were compared to the No DTA level. (A) DTA dependent decrease in cell viability induced by siRNA in HUH7 cells. The siRNA used were: siCont: control siRNA; S4: siRNA S4; S5: siRNA S5. The numbers above the bars indicated the % viability obtained with each siRNA. P-values are indicated for the specific siRNAs. (B) DTA dependent decrease in cell viability induced by miRNA in U251 cells. The “Const DTA” construct had no UIR, with the DTA transgene directly driven by the CMV promoter. Each bar on the X-axis stands for a construct containing different TS region. The “sTS” control was the 4ORF construct with target sites for siRNAs S4 and S5. The miRNAs for which fully matched target sites were included in the TS are indicated below the bars. The relative level of expression of the miRNAs in the cells (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0115327#pone-0115327-t002" target="_blank">Table 2</a>) are marked as L (Low) or H (High). The numbers above the bars of the siRNA indicated the % viability obtained with each siRNA. The experiments were repeated 3 and 4 times, respectively, for A and B. Each experiment was done in triplicates. Statistical analysis was done by T-test and the bars represent standard error. P value for the construct with target sites for miRNAs 21-5p, 125b-5p, 1273g-5p was 1.2*e(−10).</p