Genome amplification and gene expression in the ciliate macronucleus

The focus of this review is on the micronucleus and macronucleus in the ciliated protozoa and the organization and function of the DNA molecules within them. We present (1) some of the structural and functional differences which are known, (2) the genetic evidence for macronuclear units, (3) two hypotheses for the organization of the DNA molecules in the macronucleus to explain these units, and (4) experiments designed to discriminate between these hypotheses. We conclude that the size of the genome is not reduced in the macronucleus and that there are 45 copies of the haploid genome present in the macronucleus of normal strains of Tetrahymena pyriformis and 800 copies in the macronucleus of Paramecium aurelia . The ciliate genome is relatively simple in terms of repeated sequences. However, not all copies of the genes present in the macronucleus may be identical since fractions of differing thermal stability appear after renaturation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44178/1/10528_2004_Article_BF00486122.pd

The Quantum Mind: Alternative Ways of Reasoning with Uncertainty

© 2018, Ontario Institute for Educational Studies (OISE). Human reasoning about and with uncertainty is often at odds with the principles of classical probability. Order effects, conjunction biases, and sure-thing inclinations suggest that an entirely different set of probability axioms could be developed and indeed may be needed to describe such habits. Recent work in diverse fields, including cognitive science, economics, and information theory, explores alternative approaches to decision theory. This work considers more expansive theories of reasoning with uncertainty while continuing to recognize the value of classical probability. In this paper, we discuss one such alternative approach, called quantum probability, and explore its applications within decision theory. Quantum probability is designed to formalize uncertainty as an ontological feature of the state of affairs, offering a mathematical model for entanglement, de/coherence, and interference, which are all concepts with unique onto-epistemological relevance for social theorists working in new and trans-materialisms. In this paper, we suggest that this work be considered part of the quantum turn in the social sciences and humanities. Our aim is to explore different models and formalizations of decision theory that attend to the situatedness of judgment. We suggest that the alternative models of reasoning explored in this article might be better suited to queries about entangled mathematical concepts and, thus, be helpful in rethinking both curriculum and learning theory

Strict control of transgene expression in a mouse model for sensitive biological applications based on RMCE compatible ES cells.

Recombinant mouse strains that harbor tightly controlled transgene expression proved to be indispensible tools to elucidate gene function. Different strategies have been employed to achieve controlled induction of the transgene. However, many models are accompanied by a considerable level of basal expression in the non-induced state. Thereby, applications that request tight control of transgene expression, such as the expression of toxic genes and the investigation of immune response to neo antigens are excluded. We developed a new Cre/loxP-based strategy to achieve strict control of transgene expression. This strategy was combined with RMCE (recombinase mediated cassette exchange) that facilitates the targeting of genes into a tagged site in ES cells. The tightness of regulation was confirmed using luciferase as a reporter. The transgene was induced upon breeding these mice to effector animals harboring either the ubiquitous (ROSA26) or liver-specific (Albumin) expression of CreER(T2), and subsequent feeding with Tamoxifen. Making use of RMCE, luciferase was replaced by Ovalbumin antigen. Mice generated from these ES cells were mated with mice expressing liver-specific CreER(T2). The transgenic mice were examined for the establishment of an immune response. They were fully competent to establish an immune response upon hepatocyte specific OVA antigen expression as indicated by a massive liver damage upon Tamoxifen treatment and did not show OVA tolerance. Together, this proves that this strategy supports strict control of transgenes that is even compatible with highly sensitive biological readouts