Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 11 of 11
Full-Text Articles in Entire DC Network
Genome-Wide Occupancy Of Polycomb Group Proteins And Chromatin Remodeler Splayed And Their Interplay In Arabidopsis, Jie Shu
Electronic Thesis and Dissertation Repository
The Polycomb group (PcG) proteins form two protein complexes, Polycomb repressive complex 1 (PRC1) and PRC2, which are key epigenetic regulators in eukaryotes. PRC2 represses gene expression by catalyzing trimethylation of histone H3 lysine 27 (H3K27me3). In Arabidopsis thaliana, CURLY LEAF (CLF) and SWINGER (SWN) are two major H3K27 methyltransferases, playing essential roles in plant growth and development. Despite their importance, genome-wide occupancy profiles of CLF and SWN have not yet been determined and compared. In this thesis, I generated transgenic lines expressing GFP-tagged CLF/SWN and determined the genome-wide distributions of CLF and SWN in Arabidopsis seedlings. I also …
Defective Aba-Mediated Sugar Signalling Pathway In An Established Arabidopsis Thaliana Cell Suspension Culture Explains Its Stay-Green Phenotype At High Sugar Concentrations, Avery Mccarthy
Electronic Thesis and Dissertation Repository
An unusual sugar insensitive phenotype was identified in an established cell suspension culture of Arabidopsis thaliana. We characterized the physiology, biochemistry and genetics of the sugar insensitive cell culture, in order to identify factors contributing to the phenotype. Chlorophyll levels of the cell suspension culture were insensitive to high sucrose (6-15% w/v) and maintained a green phenotype. Immunoblotting indicated that levels of key photosynthetic proteins (PsaA, Lhcb2 and Rubisco) increased as a function of external sucrose concentration. The green cell culture was photosynthetically competent based on light-dependent, CO2-saturated rates of O2 evolution as well as Fv/Fm …
The Mystery Of Nuclear Localization Of Arogenate Dehydratase5 From Arabidopsis Thaliana, Sara Abolhassani Rad
The Mystery Of Nuclear Localization Of Arogenate Dehydratase5 From Arabidopsis Thaliana, Sara Abolhassani Rad
Electronic Thesis and Dissertation Repository
Arogenate dehydratases (ADTs) have been identified to catalyze the last step of phenylalanine (Phe) biosynthesis in plants. All ADTs have a transit peptide sequence that targets them into the chloroplasts where the biosynthesis of Phe happens. Subcellular localization studies using fluorescently tagged Arabidopsis thaliana ADTs demonstrated that all six ADTs localize to chloroplast stromules (stroma filled tubules). However, one member of this family, ADT5, was also detected in the nucleus. As dual targeting of proteins to different cell compartments is an indication of multifunctionality, ADT5 nuclear localization suggests that this member of the ADT protein family is a moonlighting protein …
Glucan Synthase-Like 8: A Key Player In Early Seedling Development In Arabidopsis, Behnaz Saatian
Glucan Synthase-Like 8: A Key Player In Early Seedling Development In Arabidopsis, Behnaz Saatian
Electronic Thesis and Dissertation Repository
Plants’ cell walls have unique chemical composition and features which enable them to play essential roles during plant development as shaping the cells and providing intercellular communication between adjacent cells. Polysaccharides, including callose, and glycoproteins are known as the main constituents of the cell wall. Callose, a linear β-1,3-glucan polymer, is accumulated at the cell plate during cytokinesis, in plasmodesmata, where it regulates cell-to-cell communication, in dormant phloem, where it seals sieve plates after mechanical injury and pathogen attack, and in male and female gametophytes. GLUCAN SYNTHASE-LIKE (GSL) genes in Arabidopsis comprise a family of 12 members. A …
Identification Of Putative Plant Defense Genes Using A Novel Hydroponic Co-Cultivation Technique For Studying Plant-Pathogen Interaction, Naeem Nathoo
Electronic Thesis and Dissertation Repository
Previous work on identifying the molecular mechanisms mediating plant-pathogen interactions and reciprocal host responses have little emphasis on developing models that closely resemble host-microbe interaction in planta. This work establishes an amalgamated model of interaction wherein successful pathogens elicit and overcome host defenses activated by microbial signatures and virulence factors. Using a hydroponic co-cultivation model, we assessed the responses of Arabidopsis thaliana Col-0 to Agrobacterium tumefaciens C58 to ameliorate limitations of previous approaches. Comparisons of differential gene expression between directly and indirectly affected host sites by microarray analysis revealed both reactive and pro-active defense responses, respectively. Selected homozygous single-gene …
Arabidopsis Chromatin Remodeler Brahma: Its Functional Interplay With Polycomb Proteins And The Ref6 Histone Demethylase, Chenlong Li
Electronic Thesis and Dissertation Repository
BRAHMA (BRM) is a SWI/SNF-type chromatin remodeling ATPase that plays an important role in regulation of gene expression. Tri-methylation of lysine 27 on histone H3 (H3K27me3) is a histone modification that is associated with transcriptionally repressed genes and catalyzed by Polycomb Group (PcG) proteins. BRM has been proposed to antagonize the function of PcG proteins but the underlying molecular mechanism is unclear. To understand how BRM regulates the function of PcG proteins during plant development, a genome-wide analysis of H3K27me3 in brm mutant was performed using chromatin immunoprecipitation followed by next generation sequencing (ChIP-seq). Loss of BRM leads to increased …
Changing The Substrate Specificity Of Arogenate Dehydratases (Adts) From Arabidopsis Thaliana., Megan Es Smith-Uffen
Changing The Substrate Specificity Of Arogenate Dehydratases (Adts) From Arabidopsis Thaliana., Megan Es Smith-Uffen
Electronic Thesis and Dissertation Repository
Phenylalanine (Phe), an essential aromatic amino acid, serves as a precursor for protein synthesis and a variety of secondary metabolites in plants. Two pathways are known for Phe biosynthesis. In the first, prephenate dehydratases (PDTs) convert prephenate to phenylpyruvate, which is transaminated to Phe. In the second, prephenate is transaminated to arogenate, which is converted to Phe by arogenate dehydratases (ADTs). ADTs and PDTs are structurally very similar, as are their substrates. Six ADTs (ADT1-ADT6) have been identified in Arabidopsis thaliana. ADT1 and ADT2 can recognize both prephenate and arogenate as substrates whereas ADT3-ADT6 are solely arogenate-accepting. Twenty ADT domain-swapping …
Two Spotted Spider Mite (Tetranychus Urticae) Selection To Arabidopsis Thaliana, Huzefa Ratlamwala
Two Spotted Spider Mite (Tetranychus Urticae) Selection To Arabidopsis Thaliana, Huzefa Ratlamwala
Electronic Thesis and Dissertation Repository
Spider mite feeding on A. thaliana induces the production of indole glucosinolates (IGs), plant secondary metabolites that negatively affect mite performance. In this study I conducted selection experiments on A. thaliana with varying levels of IGs, to determine if mites could adapt to IGs and other defense compounds. After 12 months, mites reared on host with IGs performed significantly better on A. thaliana than mites maintained on beans. However, an adaptation cost was detected between selected mite lines and their ancestral host. The qRT-PCR data on different mite lines revealed that the detoxification genes previously identified may only be involved …
Arabidopsis Thaliana-Spider Mite Interaction: Plant Perception, Signalling, And Response, Kristie A. Bruinsma
Arabidopsis Thaliana-Spider Mite Interaction: Plant Perception, Signalling, And Response, Kristie A. Bruinsma
Electronic Thesis and Dissertation Repository
The two-spotted spider mite, Tetranychus urticae, is a cell-content feeding chelicerate herbivore, feeding on over 1000 plant species, one of which is Arabidopsis thaliana. This research uses microarray data from two A. thaliana accessions that differ in susceptibility to spider mite feeding to identify how the plant defends itself against this herbivore. Mutant analysis of induced plant defense pathways and physiological assays of mite performance indicate that A. thaliana utilizes: a) damage associated molecular pattern receptors, PEPR1 and PEPR2, to aid in perception of attack; b) jasmonic acid as the key phytohormone involved in resistance signalling; and c) …
Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1, Hemanta Raj Mainali
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 …
Create The Scene And Watch The Show Unfold: Following Vegetative To Embryonic Developmental Transitions By Over-Expressing Lec2 In Leaves Of Arabidopsis Thaliana, Mistianne Feeney
Create The Scene And Watch The Show Unfold: Following Vegetative To Embryonic Developmental Transitions By Over-Expressing Lec2 In Leaves Of Arabidopsis Thaliana, Mistianne Feeney
Electronic Thesis and Dissertation Repository
During seed development, the lytic vacuole (LV) is replaced by a protein storage vacuole (PSV) which specializes in accumulating seed storage proteins (SSPs). As seed protein reserves are mobilized upon germination, the PSV is once again replaced by the LV which takes on different roles in vegetative tissues. Cellular events occurring during these developmental transitions are not well understood, particularly, the transition between vacuole types. This research investigates whether PSVs can exist in leaves. To study vacuole transitions in leaves, an Arabidopsis thaliana line over-expressing the LEAFY COTYLEDON2 (LEC2) transcription factor was used. LEC2 is a master regulator of embryogenesis …