Publications by authors named "Donna M Cassidy-Hanley"

Mitochondrial cox1 689 bp barcodes are routinely used for identification of Tetrahymena species. Here, we examine whether two shorter nuclear sequences, the 5.8S rRNA gene region and the intergenic region between H3 and H4 histone genes, might also be useful either singly or in combination with each other or cox1.

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The requirement for low cost manufacturing makes bacterial cells a logical platform for the production of recombinant subunit vaccines for malaria. However, protein solubility has been a major stumbling block with prokaryotic expression systems. Notable examples include the transmission blocking vaccine candidates, Pfs25 and Pfs48/45, which are almost entirely insoluble when expressed as recombinant proteins in Escherichia coli.

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Immobilization antigens (i-antigens) are surface membrane proteins that are widely recognized to be the ideal candidates as vaccines antigens for immunization against Cryptocaryon irritans. In this study, we cloned a putative i-antigen gene from C. irritans, which was expressed in all three stages of the C.

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Although the presence of endosymbiotic rickettsial bacteria, specifically Megaira, has been reported in diverse habitats and a wide range of eukaryotic hosts, it remains unclear how broadly Megaira are distributed in a single host species. In this study we seek to address whether Megaira are present in most, if not all isolates, of the parasitic ciliate . Conserved regions of bacterial 16S rRNA genes were either PCR amplified, or assembled from deep sequencing data, from 18 isolates/populations of sampled worldwide (Brazil, Taiwan, and USA).

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The germline genome of the binucleated ciliate undergoes programmed chromosome breakage and massive DNA elimination to generate the somatic genome. Here, we present a complete sequence assembly of the germline genome and analyze multiple features of its structure and its relationship to the somatic genome, shedding light on the mechanisms of genome rearrangement as well as the evolutionary history of this remarkable germline/soma differentiation. Our results strengthen the notion that a complex, dynamic, and ongoing interplay between mobile DNA elements and the host genome have shaped chromosome structure, locally and globally.

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Ichthyophthirius multifiliis is the etiologic agent of "white spot", a commercially important disease of freshwater fish. As a parasitic ciliate, I. multifiliis infects numerous host species across a broad geographic range.

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Tetrahymena has been a useful model in basic research in part due to the fact it is easy to grow in culture and exhibits a range of complex processes, all within a single cell. For these same reasons Tetrahymena has shown enormous potential as a teaching tool for fundamental principles of biology at multiple science education levels that can be integrated into K-12 classrooms and undergraduate and graduate college laboratory courses. These Tetrahymena-based teaching modules are inquiry-based experiences that are also effective at teaching scientific concepts, retaining students in science, and exciting students about the scientific process.

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The ciliated protozoan Tetrahymena thermophila has been an important model system for biological research for many years. During that time, a variety of useful strains, including highly inbred stocks, a collection of diverse mutant strains, and wild cultivars from a variety of geographical locations have been identified. In addition, thanks to the efforts of many different laboratories, optimal conditions for growth, maintenance, and storage of Tetrahymena have been worked out.

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Background: Ichthyophthirius multifiliis, commonly known as Ich, is a highly pathogenic ciliate responsible for 'white spot', a disease causing significant economic losses to the global aquaculture industry. Options for disease control are extremely limited, and Ich's obligate parasitic lifestyle makes experimental studies challenging. Unlike most well-studied protozoan parasites, Ich belongs to a phylum composed primarily of free-living members.

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The parasitic ciliate, Ichthyophthirius multifiliis (Ich), is among the most important protozoan pathogens of freshwater fish. Ichthyophthirius cannot be grown in cell culture, and the development of effective prophylactic and therapeutic treatments has been hampered by a lack of information regarding genes involved in virulence, differentiation and growth. To help address this issue, we have generated EST libraries from the two major stages of the parasite life cycle that infect and develop within host tissues.

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Background: Tetrahymena thermophila, a widely studied model for cellular and molecular biology, is a binucleated single-celled organism with a germline micronucleus (MIC) and somatic macronucleus (MAC). The recent draft MAC genome assembly revealed low sequence repetitiveness, a result of the epigenetic removal of invasive DNA elements found only in the MIC genome. Such low repetitiveness makes complete closure of the MAC genome a feasible goal, which to achieve would require standard closure methods as well as removal of minor MIC contamination of the MAC genome assembly.

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