Tall fescue (Lolium arundinaceum) is a highly adaptable forage, pasture and turf grass that is grown on over 14 M ha in the eastern half of the United States and in other temperate regions of the ...world. A significant factor in adaptability, productivity and stand persistence is in part due to the presence of an intercellular, seed-transmissible, endophytic fungus, Epichloë coenophiala. Epichloë endophytes have been shown to produce a number of alkaloid compounds only in planta, some that are beneficial in repelling insects, while others are toxic to animals. The goal of this work was to monitor the level of the ergot and loline (classified as pyrrolizidine) alkaloid accumulation in individual plants to determine the plant genotype contribution to alkaloid concentrations. The experimental design consisted of sixteen tall fescue KY31 clones in a space-planted, replicated trial over three years. Our results demonstrated that while changes in the alkaloid concentrations for each plant/endophyte genotype were observed over the three years, the overall alkaloid levels remained relatively constant when compared to other plant/endophyte genotypes combinations in the field. Additionally, overall levels of the ergot and loline alkaloid accumulation did not vary in the same way over the three years. Since the E. coenophiala endophyte genotype was the same across all clones, our results indicate that it is the plant genotype that is responsible for determining alkaloid levels in each plant, and suggest that the signal(s) from the plant to the endophyte may not be the same for ergot and loline alkaloid production.
La podredumbre negra de la mazorca (BPR), causada por varias especies del género Phytophthora, es una de las enfermedades más limitantes para la producción de cacao ya que se presenta en todas las ...regiones productoras del mundo y genera importantes pérdidas. El objetivo de este estudio fue establecer la respuesta a esta infección en seis clones de cacao (EET8, IMC67, TSH565, PA46, ICS95 y CCN51), mediante una prueba de inoculación en frutos desprendidos utilizando cinco aislados de P. palmivora de cinco regiones productoras. Se evaluó la incidencia y severidad de la enfermedad en las vainas desprendidas a los seis y diez días después de la inoculación (DAI). El clon CCN51 se clasificó como susceptible y los clones IMC67 y PA46 como moderadamente susceptibles a los seis DAI. Todos los clones evaluados fueron categorizados como susceptibles a los diez DAI. Los aislamientos HURV19 de P. palmivora mostraron la mayor agresividad en comparación con ANYA228, que resultó ser el menos agresivo.
Many people think human reproductive cloning should be a crime. In America some states have already outlawed cloning and Congress is working to enact a national ban. Meanwhile, scientific research ...continues, both in America and abroad and soon reproductive cloning may become possible. If that happens, cloning cannot be stopped. Infertile couples and others will choose to have babies through cloning, even if they have to break the law. This book explains that the most common objections to cloning are false or exaggerated. The objections reflect and inspire unjustified stereotypes about human clones and anti-cloning laws reinforce these stereotypes and stigmatize human clones as subhuman and unworthy of existence. This injures not only human clones, but also the egalitarianism upon which our society is based. Applying the same reasoning used to invalidate racial segregation, this book argues that anti-cloning laws violate the equal protection guarantee and are unconstitutional.
Human Cloning Macintosh, Kerry Lynn
10/2012, Letnik:
v.Series Number 21
eBook
Since Dolly the sheep was born, controversy has swirled around the technology of cloning. We recoil at the prospect of human copies, manufactured men and women, nefarious impersonators and ...resurrections of the dead. Such reactions have serious legal consequences: lawmakers have banned stem cell research along with the cloning of babies. But what if our minds have been playing tricks on us? What if everything we thought we knew about human cloning is rooted in intuition rather than fact? Human Cloning: Four Fallacies and their Legal Consequences is a rollicking ride through science, psychology and the law. Drawing on sources ranging from science fiction films to the Congressional Record, this book unmasks the role that psychological essentialism has played in bringing about cloning bans. It explains how hidden intuitions have caused conservatives and liberals to act contrary to their own most cherished ideals and values.
Molecular manipulations, including DNA cloning and mutagenesis are basic tools used on a routine basis in all life-science disciplines. Over the last decade new methodologies have emerged that ...facilitated and expanded the applications for DNA cloning and mutagenesis. Ligation-Independent Cloning (LIC) techniques were developed and replaced the classical Ligation Dependent Cloning (LDC) platform. Restriction Free (RF) cloning was originally developed for introduction of foreign DNA into a plasmid at any predetermined position. RF cloning is based on PCR amplification of a DNA fragment, which serves as a mega-primer for the linear amplification of the vector and insert. Here we present several novel applications of the Restriction Free (RF) cloning platform for DNA cloning and mutagenesis. The new applications include simultaneous cloning of several DNA fragments into distinct positions within an expression vector, simultaneous multi-component assembly, and parallel cloning of the same PCR product into a series of different vectors. In addition, we have expanded the application of the RF cloning platform for multiple alterations of the target DNA, including simultaneous multiple-site mutagenesis and simultaneous introduction of deletions and insertions at different positions. We further demonstrate the robustness of the new applications for facilitating recombinant protein expression in the Escherichia coli system.
The advent of new DNA sequencing technologies leads to a dramatic increase in the number of available genome sequences and therefore of target genes with potential for functional analysis. The ...insertion of these sequences into proper expression vectors requires a simple an efficient cloning method. In addition, when expressing a target protein, quite often it is necessary to evaluate different DNA constructs to achieve a soluble and homogeneous expression of the target with satisfactory yields. The development of new molecular methods made possible the cloning of a huge number of DNA sequences in a high-throughput manner, necessary for meeting the increasing demands for soluble protein expression and characterization. In this chapter several molecular methods suitable for high-throughput cloning are reviewed.
Abstract
Development of strains for efficient production of chemicals and pharmaceuticals requires multiple rounds of genetic engineering. In this study, we describe construction and characterization ...of EasyClone vector set for baker's yeast Saccharomyces cerevisiae, which enables simultaneous expression of multiple genes with an option of recycling selection markers. The vectors combine the advantage of efficient uracil excision reaction-based cloning and Cre-LoxP-mediated marker recycling system. The episomal and integrative vector sets were tested by inserting genes encoding cyan, yellow, and red fluorescent proteins into separate vectors and analyzing for co-expression of proteins by flow cytometry. Cells expressing genes encoding for the three fluorescent proteins from three integrations exhibited a much higher level of simultaneous expression than cells producing fluorescent proteins encoded on episomal plasmids, where correspondingly 95% and 6% of the cells were within a fluorescence interval of Log10 mean ± 15% for all three colors. We demonstrate that selective markers can be simultaneously removed using Cre-mediated recombination and all the integrated heterologous genes remain in the chromosome and show unchanged expression levels. Hence, this system is suitable for metabolic engineering in yeast where multiple rounds of gene introduction and marker recycling can be carried out.
EasyClone genetical toolbox allows faster development of yeast strains for biotechnological applications.
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