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  1. Sycon coactum - transcriptome [Download]

    Title: Sycon coactum - transcriptome
    Creator: Leys, Sally
    Description: Sponges (Porifera) are among the earliest evolving metazoans. Their filter-feeding body plan based on choanocyte chambers organized into a complex aquiferous system is so unique among metazoans that it either reflects an early divergence from other animals prior to the evolution of features such as muscles and nerves, or that sponges lost these characters. Analyses of the Amphimedon and Oscarella genomes support this view of uniqueness—many key metazoan genes are absent in these sponges—but whether this is generally true of other sponges remains unknown. We studied the transcriptomes of eight sponge species in four classes (Hexactinellida, Demospongiae, Homoscleromorpha, and Calcarea) specifically seeking genes and pathways considered to be involved in animal complexity. For reference, we also sought these genes in transcriptomes and genomes of three unicellular opisthokonts, two sponges (A. queenslandica and O. carmela), and two bilaterian taxa. Our analyses showed that all sponge classes share an unexpectedly large complement of genes with other metazoans. Interestingly, hexactinellid, calcareous, and homoscleromorph sponges share more genes with bilaterians than with nonbilaterian metazoans. We were surprised to find representatives of most molecules involved in cell–cell communication, signaling, complex epithelia, immune recognition, and germ-lineage/sex, with only a few, but potentially key, absences. A noteworthy finding was that some important genes were absent from all demosponges (transcriptomes and the Amphimedon genome), which might reflect divergence from main-stem lineages including hexactinellids, calcareous sponges, and homoscleromorphs. Our results suggest that genetic complexity arose early in evolution as shown by the presence of these genes in most of the animal lineages, which suggests sponges either possess cryptic physiological and morphological complexity and/or have lost ancestral cell types or physiological processes.
    Subjects: Porifera, calcareous sponge, Sycon coactum, sponge transcriptome
    Date Created: 2014/02/27
  2. Spongilla lacustris transcriptome [Download]

    Title: Spongilla lacustris transcriptome
    Creator: Leys, Sally
    Description: Sponges (Porifera) are among the earliest evolving metazoans. Their filter-feeding body plan based on choanocyte chambers organized into a complex aquiferous system is so unique among metazoans that it either reflects an early divergence from other animals prior to the evolution of features such as muscles and nerves, or that sponges lost these characters. Analyses of the Amphimedon and Oscarella genomes support this view of uniqueness—many key metazoan genes are absent in these sponges—but whether this is generally true of other sponges remains unknown.We studied the transcriptomes of eight sponge species in four classes (Hexactinellida, Demospongiae, Homoscleromorpha, and Calcarea) specifically seeking genes and pathways considered to be involved in animal complexity. For reference, we also sought these genes in transcriptomes and genomes of three unicellular opisthokonts, two sponges (A. queenslandica and O. carmela), and two bilaterian taxa. Our analyses showed that all sponge classes share an unexpectedly large complement of genes with other metazoans. Interestingly, hexactinellid, calcareous, and homoscleromorph sponges share more genes with bilaterians than with nonbilaterian metazoans. We were surprised to find representatives ofmostmolecules involved in cell–cell communication, signaling, complex epithelia, immune recognition, and germ-lineage/sex, with only a few, but potentially key, absences. A noteworthy finding was that some important genes were absent from all demosponges (transcriptomes and the Amphimedon genome), which might reflect divergence from main-stem lineages including hexactinellids, calcareous sponges, and homoscleromorphs. Our results suggest that genetic complexity arose early in evolution as shown by the presence of these genes in most of the animal lineages, which suggests sponges either possess cryptic physiological and morphological complexity and/or have lost ancestral cell types or physiological processes.
    Subjects: Spongilla lacustris, Freshwater sponge, Porifera transcriptome
    Date Created: 2014/02/27
  3. Aphrocallistes vastus Trinity transcriptome [Download]

    Title: Aphrocallistes vastus Trinity transcriptome
    Creator: Leys, Sally
    Description: Sponges (Porifera) are among the earliest evolving metazoans. Their filter-feeding body plan based on choanocyte chambers organized into a complex aquiferous system is so unique among metazoans that it either reflects an early divergence from other animals prior to the evolution of features such as muscles and nerves, or that sponges lost these characters. Analyses of the Amphimedon and Oscarella genomes support this view of uniqueness—many key metazoan genes are absent in these sponges—but whether this is generally true of other sponges remains unknown.We studied the transcriptomes of eight sponge species in four classes (Hexactinellida, Demospongiae, Homoscleromorpha, and Calcarea) specifically seeking genes and pathways considered to be involved in animal complexity. For reference, we also sought these genes in transcriptomes and genomes of three unicellular opisthokonts, two sponges (A. queenslandica and O. carmela), and two bilaterian taxa. Our analyses showed that all sponge classes share an unexpectedly large complement of genes with other metazoans. Interestingly, hexactinellid, calcareous, and homoscleromorph sponges share more genes with bilaterians than with nonbilaterian metazoans. We were surprised to find representatives ofmostmolecules involved in cell–cell communication, signaling, complex epithelia, immune recognition, and germ-lineage/sex, with only a few, but potentially key, absences. A noteworthy finding was that some important genes were absent from all demosponges (transcriptomes and the Amphimedon genome), which might reflect divergence from main-stem lineages including hexactinellids, calcareous sponges, and homoscleromorphs. Our results suggest that genetic complexity arose early in evolution as shown by the presence of these genes in most of the animal lineages, which suggests sponges either possess cryptic physiological and morphological complexity and/or have lost ancestral cell types or physiological processes.
    Subjects: Porifera, Transcriptome, Glass sponge, Hexactinellid
    Date Created: 2014/02/11
  4. Investigation of meiotic organelle checkpoint functions by Drosophila Myt1 [Download]

    Title: Investigation of meiotic organelle checkpoint functions by Drosophila Myt1
    Creator: Ramya Varadarajan
    Description: Meiosis in eukaryotes includes a developmentally programmed pre-meiotic G2 phase arrest before the onset of MI division mediated by inhibitory phosphorylation of Cdk1. There are two inhibitory kinases, Wee1 and Myt1. Myt1 mediated Cyclin B-Cdk1 regulation serves as a conserved mechanism for maintaining pre-meiotic oocyte arrest in many animal models. Earlier reports from the Campbell lab, however, have shown that loss of Myt1 activity affected multiple aspects of Drosophila spermatogenesis resulting in male sterility. The conserved meiotic checkpoint function of Myt1 was hypothesized to account for myt1 mutant male sterility, as Drosophila spermatocytes normally undergo a developmentally regulated pre-meiotic G2 phase arrest before MI. This possibility, however, has not been tested. Here I show that loss of Myt1 activity neither affects the timing of pre-meiotic G2 phase arrest nor the overall coordination of G2/MI transition. Instead, the phenotypic analysis of myt1 mutants indicated that Myt1 activity is required for structural integrity of a germline specific membranous cytoskeletal organelle called the fusome (or intercellular bridges). I found that inhibition of Cyclin A-Cdk1 during early spermatocyte development requires Myt1 activity to prevent fusomes from premature Cdk1 activation. Mis-regulation of Cyclin A-Cdk1 during spermatocyte development also perturbed premature centrioles dis-engagement, producing multipolar meiotic spindles resulting in aneuploidy of myt1 meiocytes. I conclude that the role of Myt1 during pre-meiotic G2 phase arrest of male meiosis is to regulate discrete checkpoint mechanisms that are used to spatially and temporally coordinate cytoplasmic organelle behavior with the nuclear events of meiotic progression that are triggered by Cdc25Twe-mediated Cdk1 activation, at G2/MI.
    Subjects: Myt1 kinase, Drosophila spermatogenesis, fusome
    Date Created: 2015/09/28
  5. Emergence Phenology of Adult Apanteles polychrosidis (Hymenoptera: Braconidae) [Download]

    Title: Emergence Phenology of Adult Apanteles polychrosidis (Hymenoptera: Braconidae)
    Creator: Dombrowsky, Emily A.
    Subjects: Apanteles polychrosidis
  6. Insights into temperature adaptation in the Thermotogae gained through transcriptomics and comparative genomics - Appendices [Download]

    Title: Insights into temperature adaptation in the Thermotogae gained through transcriptomics and comparative genomics - Appendices
    Creator: Pollo, Stephen M. J.
    Description: These are appendices C - G for the University of Alberta M.Sc. thesis: Pollo, Stephen M. J. 2014. Insights into temperature adaptation in the Thermotogae gained through transcriptomics and comparative genomics
    Subjects: Bacteria, RNA-Seq, Temperature Adaptation, Kosmotoga olearia, Comparative genomics, Thermotogae, Transcriptomics
    Date Created: 2014
  7. Pollen-mediated gene flow from transgenic safflower (Carthamus tinctorius L.) intended for plant molecular farming to conventional safflower. [Download]

    Title: Pollen-mediated gene flow from transgenic safflower (Carthamus tinctorius L.) intended for plant molecular farming to conventional safflower.
    Creator: McPherson M.A.
    Subjects: gene flow, pollen/genetics, Plants, genetically modified/genetics, Carthamus tinctorius/genetics
    Date Created: 2009
  8. Evaluation of Beauvericinas a Marker for Beauveria bassiana virulence and its implication for greenhouse pest management [Download]

    Title: Evaluation of Beauvericinas a Marker for Beauveria bassiana virulence and its implication for greenhouse pest management
    Creator: Rajput, Sunil
    Subjects: Beauveria bassiana, Biocontrol, Invertebrate pathology, thrips, Greenhouse, Mycotoxins
    Date Created: 2006
  9. On the Firm Foundation of Curiousity : The Early History of Biology at the University of Alberta [Download]

    Title: On the Firm Foundation of Curiousity : The Early History of Biology at the University of Alberta
    Creator: Acorn, John
    Description: History of the University of Alberta Department of Biological Sciences.
    Subjects: History, University of Alberta. Department of Biological Sciences
    Date Created: 2008
  10. Scale-eating cichlids: From hand(ed) to mouth. [Download]

    Title: Scale-eating cichlids: From hand(ed) to mouth.
    Creator: Palmer, A.R.
    Description: Two recent studies in BMC Biology and Evolution raise important questions about a textbook case of frequency-dependent selection in scale-eating cichlid fishes. They also suggest a fascinating new line of research testing the effects of handed behavior on morphological asymmetry.
    Subjects: scale-eating cichlids, morphological asymmetry, handed behavior, mouth bending
    Date Created: 2010