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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 Title: Emergence Phenology of Adult Apanteles polychrosidis (Hymenoptera: Braconidae) Creator: Dombrowsky, Emily A. Subjects: Apanteles polychrosidis 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 Title: Caloptilia fraxinella Creator: Wist, Tyler Subjects: Caloptila fraxinella 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
Evaluation of Beauvericinas a Marker for Beauveria bassiana virulence and its implication for greenhouse pest management
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
Pollen-mediated gene flow from transgenic safflower (Carthamus tinctorius L.) intended for plant molecular farming to conventional safflower.
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
Insights into temperature adaptation in the Thermotogae gained through transcriptomics and comparative genomics - Appendices
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 Title: Frankliniella occidentalis oviposition video Creator: Rajput, S. Description: Frankliniella occidentalis probing and oviposition video. Ventral view of an adult female thrips ovipositing an egg into deionized water through stretched parafilm. Video recorded using a Nikon Coolpix 775 digital camera mounted on a stereo microscope. Please also refer to Frankliniella occidentalis and Hercinothrips femoralis embryogenesis laboratory notes. Subjects: Thrips embryogenesis, western flower thrips, thrips oviposition, thrips probing, thrips egg laying Date Created: 2002