Molecular Biology Commons^™

Molecular Identification And Characterization Of Viral Pathogens Infecting Sweet Cherry, Aaron J. Simkovich

Electronic Thesis and Dissertation Repository

Stone fruits are a valuable crop grown worldwide, however pathogens such as viruses threaten fruit production by reducing tree health and fruit yield. In an orchard within the Niagara region of Ontario, symptoms typical of viral infection such as chlorosis and leaf deformation were seen on sweet cherry (Prunus avium L.) trees. Next generation sequencing was performed on symptomatic and asymptomatic leaves and four viruses were identified. On the tree displaying the most severe symptoms, Prune dwarf virus (PDV), was the only virus detected. A survey conducted during this work showed 42% of cherry trees on a single …

The Role Of H3k4 Methyltransferases In Drosophila Memory, Nicholas Raun

Electronic Thesis and Dissertation Repository

Gene transcription required for long-term memory requires the modification of histones. However, there are still many uncertainties about the identity and spatial expression of genes regulated by histone modifications during memory related processes. In this project I examined the role of Drosophila melanogaster methyltransferases Set1 and trx in courtship memory. Genetic knockdown of Set1 and trx in the mushroom body (MB) revealed that Set1 was necessary for short- and long-term memory, while trx was only required for long-term memory. Transcriptional profiling of MBs following trx-knockdown revealed expression changes in MB-enriched genes and genes involved in RNA processing. Among the …

The Association Between Oxidative Stress, Cellular Differentiation And Galectins In Human Promyelocytic Leukemia Cells (Hl-60), James R. Vinnai

Electronic Thesis and Dissertation Repository

Galectins are a group of β-galactoside-binding proteins involved in different cellular processes including stress responses and differentiation. The role and expression of galectins under oxidative stress and during neutrophilic differentiation was examined in HL-60 cells. Galectin gene (LGALS), and galectin protein expression were determined using RT-qPCR and immunoblotting, respectively. Neutrophilic differentiation was measured via a spectrofluorometric assay. DNA methylation and JNK signaling were investigated as galectin regulatory mechanisms. Menadione-induced oxidative stress, DMSO-induced differentiation, DNA hypomethylation and JNK signaling all promoted similar galectin expression profiles. Antioxidant N-acetylcysteine attenuated the menadione-induced galectin expression but only partially attenuated DMSO-induced galectin expression. …

Planting The Chalcone Reductase Family Tree: Identification And Characterization Of Chalcone Reductase Genes In Soybean, Caroline Julia Sepiol

Electronic Thesis and Dissertation Repository

Soybean (Glycine max [L.] Merr) is an important crop grown in Canada, generating $2.4 billion in sales. Though this number may be promising, soybean farmers lose about $50 million worth of yield annually due to root and stem rot disease caused by Phytophthora sojae. Many strategies have been developed to combat the infection; however, these methods are prohibitively expensive. A ‘cost effective’ approach to this problem is to select a trait naturally found in soybean that can increase resistance. One such trait is the increased production of root glyceollins. One of the key enzymes exclusively involved in glyceollin …

Sirna Targeting Of Thymidylate Synthase, Thymidine Kinase 1 And Thymidine Kinase 2 As An Anticancer Therapy: A Combinatorial Rnai Approach, Christine Di Cresce

Electronic Thesis and Dissertation Repository

Thymidylate synthase (TS) is the only de novo source of thymidylate (dTMP) for DNA synthesis and repair. Drugs targeting TS protein are a mainstay in cancer treatment but off-target effects and toxicity limit their use. Cytosolic thymidine kinase (TK1) and mitochondrial thymidine kinase (TK2) contribute to an alternative dTMP-producing pathway, by salvaging thymidine from the tumour milieu, and may modulate resistance to TS-targeting drugs. We have previously shown that TS antisense molecules (oligodeoxynucleotides, ODNs, and small interfering siRNA, siRNA) sensitize tumour cells, both in vitro and in vivo, to TS targeting drugs. As both TS and TKs contribute to cellular …

Uncovering The Molecular Link Between Mir156.Spl15 And Carotenoid Accumulation In Arabidopsis, Davood Emami Meybodi

Electronic Thesis and Dissertation Repository

Carotenoid Cleavage Dioxygenases (CCDs) are an enzyme family that cleaves specific double bonds in carotenoids. MicroR156 in Arabidopsis regulates a network of genes by repressing 10 SPL genes, among which, SPL15 was found to regulate shoot branching and carotenoid accumulation. The expression of CCD1, CCD4, CCD7, CCD8, NCED2, NCED3, NCED5, NCED6, NCED9 and SPL15 was evaluated in siliques at 10 days post anthesis and in 10-day-old roots in Arabidopsis wild type, sk156 (miR156 overexpression mutant), RS105 (miR156 overexpression line), spl15 (SPL15 knockout mutant) and two 35S:SPL15 lines. Results showed that most of CCD/NCED genes were …

Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1, Hemanta Raj Mainali

Electronic Thesis and Dissertation Repository

I identified members of the Cyclophilin (CYP) gene family in soybean (Glycine max) and characterized the GmCYP1, one of the members of soybean CYP. CYPs belong to the immunophilin superfamily with peptidyl-prolyl cis-trans isomerase (PPIase) activity. PPIase catalyzes the interconversion of the cis- and trans-rotamers of the peptidyl-prolyl amide bond of peptides. After extensive data mining, I identified 62 different CYP genes in soybean (GmCYP1 to GmCYP62), of which 8 are multi-domain proteins and 54 are single domain proteins. At least 25% of the GmCYP genes are expressed in soybean. GmCYP1 …

Involvement Of Hexokinase1 In Plant Growth Promotion As Mediated By Burkholderia Phytofimans, Jae Min Park

Electronic Thesis and Dissertation Repository

Burkholderia phytofirmans strain PsJN consistently enhanced the growth of potato plants in vitro. The role of hexokinase1 in glucose phosphorylation was investigated in plants with PsJN. Increased hexokinase1 activity only in roots of PsJN-treated plants cultivar Kennebec suggests that hexokinase1 is associated with plant root and stem growth.

Plant growth with PsJN was determined when plants were grown with different sugars at various concentrations. PsJN-treated plants expressed diverse forms of growth promotion. When growth promotion did occur, hexokinase1 activity also increased. Growth promotion and hexokinase1 activity appear to be correlated to the enzyme to recognize the substrate for catalytic activity. …