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  1. Data from Kahn et al. (submitted) [Download]

    Title: Data from Kahn et al. (submitted)
    Creator: Kahn, Amanda S
    Description: Glass sponges provide a link between the microbial loop and the benthos by feeding on bacteria, a food source too small for most other animals. Glass sponge reefs on the continental shelf of western Canada have the highest grazing rate of any benthic suspension feeding community measured to date, consuming seven times more carbon than can be supplied by vertical flux alone. How do reef sponges get enough food to sustain such high rates of feeding? We studied the feeding biology of Aphrocallistes vastus and measured stable isotope signatures of reef sponges, water, and sediments to understand the sources of carbon to the reefs and its possible fate following digestion (either through assimilation into tissue or excretion). We found that particle uptake occurs in flagellated chambers but particles are digested elsewhere in the tissue. 13C-labeled bacteria filtered by sponges remained in the tissue for at least 14 days. Fecal pellets several times larger than the particles consumed were expelled from sponges within 24 hours of feeding. Stable isotope signatures suggest that bacterioplankton ingested by the sponges come from the surrounding water column, but also glass sponge reefs may rely on substantial carbon input from sediment-borne bacteria resuspended by tidal currents.
    Subjects: stable isotope analysis, Porifera, glass sponge reefs
    Date Created: 2017
  2. Geodia barretti - Energy budget data sheet for Limnology and Oceanography [Download]

    Title: Geodia barretti - Energy budget data sheet for Limnology and Oceanography
    Creator: Sally Leys
    Description: Geodia barretti is a massive nearly spherical sponge that forms dense assemblages on the continental shelf of the North Altantic and the Norwegian Sea. We studied the metabolism of individual sponges collected using a remotely operated vehicle and maintained in large tanks with high volumes of unfiltered water brought from 160m depth. We used direct methods (In-Ex) to measure excurrent flow rates, oxygen removed, and carbon and nutrient flux through the sponges. G. barretti had very low specific filtration (0.26 mL min-1 mL-1sponge tissue) and low respiration (5.34± 0.98 nmol O2 min-1 mL-1 sponge tissue; 8.44 ± 1.51 µmol O2 hr-1 g C-1) rates in comparison to other sponges. A net release of nitrogen was detected as NO3-. Bacteria were removed from the water filtered with up to 99% efficiency, yet comprised only 5% of the sponges’ total carbon budget; the remainder consisted of dissolved organic carbon and detritus. High bacterial removal was aided by the presence of a tight gasket of cells that surrounds the collar of each choanocyte filter. A test for potential bypass canals showed removal of fluorescent microspheres until they were excreted 5-12 hours after feeding. Electron micrographs showed active uptake of E. coli ‘fed’ to the sponge as well as phagocytosis of symbiont microbes by sponge cells in the mesohyl. These data provide the first comprehensive study of metabolism in a deep-water high microbial abundance sponge.
    Subjects: Geodia, Sponge, Porifera, Feeding, carbon, Filtration
    Date Created: 2017/05/26
  3. 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
  4. 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
  5. 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
  6. 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
  7. 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
  8. 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
  9. Caloptilia fraxinella [Download]

    Title: Caloptilia fraxinella
    Creator: Wist, Tyler
    Subjects: Caloptila fraxinella
  10. 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