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Articles 1 - 30 of 122

Full-Text Articles in Cell Biology

The Role Of Ppal In The Moss Physcomitrella Patens., Noela M. Botaka May 2019

The Role Of Ppal In The Moss Physcomitrella Patens., Noela M. Botaka

College of Arts & Sciences Senior Honors Theses

Protein prenylation is a post-translational modification that involves the addition of lipid groups to the carboxy end of a target protein and is necessary for protein activity. Prenylation has important roles in the cell: targeting and localizing proteins to subcellular compartments and promoting protein-protein interactions. As a highly conserved process in eukaryotes, prenylation is especially important for plant development. In contrast to other eukaryotes, in which loss of prenylation components can be lethal, in the flowering plant Arabidopsis thaliana and the moss Physcomitrella patens, most are viable. Prior studies have shown that prenylation is involved in ABA hormone responses, polar ...


Gamete Nuclear Migration In Animals And Plants, Umma Fatema, Mohammad F. Ali, Zheng Hu, Anthony J. Clark, Tomokazu Kawashima Apr 2019

Gamete Nuclear Migration In Animals And Plants, Umma Fatema, Mohammad F. Ali, Zheng Hu, Anthony J. Clark, Tomokazu Kawashima

Plant and Soil Sciences Faculty Publications

The migration of male and female gamete nuclei to each other in the fertilized egg is a prerequisite for the blending of genetic materials and the initiation of the next generation. Interestingly, many differences have been found in the mechanism of gamete nuclear movement among animals and plants. Female to male gamete nuclear movement in animals and brown algae relies on microtubules. By contrast, in flowering plants, the male gamete nucleus is carried to the female gamete nucleus by the filamentous actin cytoskeleton. As techniques have developed from light, electron, fluorescence, immunofluorescence, and confocal microscopy to live-cell time-lapse imaging using ...


A Functional Unfolded Protein Response Is Required For Normal Vegetative Development, Yan Bao, Diane C. Bassham, Stephen H. Howell Apr 2019

A Functional Unfolded Protein Response Is Required For Normal Vegetative Development, Yan Bao, Diane C. Bassham, Stephen H. Howell

Genetics, Development and Cell Biology Publications

The unfolded protein response (UPR) is activated in plants in response to endoplasmic reticulum stress and plays an important role in mitigating stress damage. Multiple factors act in the UPR, including the membrane-associated transcription factor, BASIC LEUCINE ZIPPER 17 (bZIP17), and the membrane-associated RNA splicing factor, INOSITOL REQUIRING ENZYME1 (IRE1). We have analyzed an Arabidopsis (Arabidopsis thaliana) ire1a ire1b bzip17 triple mutant, with defects in stress signaling, and found that the mutant is also impaired in vegetative plant growth under conditions without externally applied stress. This raised the possibility that the UPR functions in plant development in the same manner ...


Combating Drug Resistance - Comparison Of The Antibiotic Effect Of Hydrastis Canadensis Extract And Pure Berberine Via Minimum Inhibitory Concentration Assay, William Luke Scott, Timothy D. Trott Apr 2019

Combating Drug Resistance - Comparison Of The Antibiotic Effect Of Hydrastis Canadensis Extract And Pure Berberine Via Minimum Inhibitory Concentration Assay, William Luke Scott, Timothy D. Trott

Research in Biology

Herbal medicines are a melee of complex organic chemicals, making it difficult to ascertain their direct mechanism of action. In contrast to mainstream pharmaceuticals, it is argued that herbal medicines are effective because of multiple constituents working synergistically. The complexity of herbal medicines may give them advantages over simpler pharmaceuticals in combating antibiotic resistant microbes, but these advantages can be difficult to quantitate. Popular literature frequently espouses the healing properties of herbal medicines, but many of these claims are not scientifically supported. Many gains could be realized in public health and medicine if more research was aimed at validating / disproving ...


Using Arabidopsis Mesophyll Protoplasts To Study Unfolded Protein Response Signaling, Yan Bao, Diane C. Bassham Dec 2018

Using Arabidopsis Mesophyll Protoplasts To Study Unfolded Protein Response Signaling, Yan Bao, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Various environmental stresses or artificial reagents can trigger unfolded protein accumulation in the endoplasmic reticulum (ER) due to the folding capacity of the ER being exceeded. This is termed ER stress, and triggers the unfolded protein response (UPR). Assays for activation of the UPR in plants include Tunicamycin (Tm)- or dithiothreitol (DTT)-mediated root growth inhibition, analysis of splicing of the UPR-responsive transcription factor bZIP60 (basic Leucine Zipper Domain 60), and upregulation of relevant UPR genes. We provide here a quick and robust method to detect UPR signaling in Arabidopsis thaliana protoplasts. This assay can also be applied to other ...


Autophagy In Crop Plants: What's New Beyond Arabidopsis?, Jie Tang, Diane C. Bassham Dec 2018

Autophagy In Crop Plants: What's New Beyond Arabidopsis?, Jie Tang, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Autophagy is a major degradation and recycling pathway in plants. It functions to maintain cellular homeostasis and is induced by environmental cues and developmental stimuli. Over the past decade, the study of autophagy has expanded from model plants to crop species. Many features of the core machinery and physiological functions of autophagy are conserved among diverse organisms. However, several novel functions and regulators of autophagy have been characterized in individual plant species. In light of its critical role in development and stress responses, a better understanding of autophagy in crop plants may eventually lead to beneficial agricultural applications. Here, we ...


Ire1b Degrades Rnas Encoding Proteins That Interfere With The Induction Of Autophagy By Er Stress In Arabidopsis Thaliana, Yan Bao, Yunting Pu, Xiang Yu, Brian D. Gregory, Renu Srivastava, Stephen H. Howell, Diane C. Bassham Aug 2018

Ire1b Degrades Rnas Encoding Proteins That Interfere With The Induction Of Autophagy By Er Stress In Arabidopsis Thaliana, Yan Bao, Yunting Pu, Xiang Yu, Brian D. Gregory, Renu Srivastava, Stephen H. Howell, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Macroautophagy/autophagy is a conserved process in eukaryotes that contributes to cell survival in response to stress. Previously, we found that endoplasmic reticulum (ER) stress induces autophagy in plants via a pathway dependent upon AT5G24360/IRE1B (INOSITOL REQUIRING 1–1), an ER membrane-anchored factor involved in the splicing of AT1G42990/BZIP60 (basic leucine zipper protein 60) mRNA. IRE1B is a dual protein kinase and ribonuclease, and here we determined the involvement of the protein kinase catalytic domain, nucleotide binding and RNase domains of IRE1B in activating autophagy. We found that the nucleotide binding and RNase activity of IRE1B, but not ...


Double-Stranded Rna Binding Protein, Staufen, Is Required For The Initiation Of Rnai In Coleopteran Insects, June-Sun Yoon, Kanakachari Mogilicherla, Dhandapani Gurusamy, Xien Chen, Shankar C. R. R. Chereddy, Subba R. Palli Aug 2018

Double-Stranded Rna Binding Protein, Staufen, Is Required For The Initiation Of Rnai In Coleopteran Insects, June-Sun Yoon, Kanakachari Mogilicherla, Dhandapani Gurusamy, Xien Chen, Shankar C. R. R. Chereddy, Subba R. Palli

Entomology Faculty Publications

RNA interference (RNAi) is being used to develop methods to control pests and disease vectors. RNAi is robust and systemic in coleopteran insects but is quite variable in other insects. The determinants of efficient RNAi in coleopterans, as well as its potential mechanisms of resistance, are not known. RNAi screen identified a double-stranded RNA binding protein (StaufenC) as a major player in RNAi. StaufenC homologs have been identified in only coleopteran insects. Experiments in two coleopteran insects, Leptinotarsa decemlineata and Tribolium castaneum, showed the requirement of StaufenC for RNAi, especially for processing of double-stranded RNA (dsRNA) to small interfering RNA ...


Anti-Inflammatory Activity Of Phenolic And Volatile Compounds In Cranberries (Vaccinium Macrocarpon L), Katherine Moore Aug 2018

Anti-Inflammatory Activity Of Phenolic And Volatile Compounds In Cranberries (Vaccinium Macrocarpon L), Katherine Moore

Theses and Dissertations

The primary objective of this study was to compare the anti-inflammatory effects of phenolic and volatile compounds extracted from cranberries. The Griess Reagent System assay was used to measure the in vitro anti-inflammatory capabilities of cranberry phenolic and volatile extracts on RAW 264.7 mouse macrophage cells. This study tested the anti-inflammatory capabilities of the cranberry phenolic and volatile extracts before, as a preventative treatment, and after, as a means of treating pre-existing inflammation, inducing inflammation with lipopolysaccharide (LPS). All experiments were conducted in the following manner, varying only in whether treated with the extracts before or after LPS: 1 ...


Assembly-Hub Function Of Er-Localized Snare Proteins In Biogenesis Of Tombusvirus Replication Compartment, Zsuzsanna Sasvari, Nikolay Kovalev, Paulina Alatriste Gonzalez, Kai Xu, Peter D. Nagy May 2018

Assembly-Hub Function Of Er-Localized Snare Proteins In Biogenesis Of Tombusvirus Replication Compartment, Zsuzsanna Sasvari, Nikolay Kovalev, Paulina Alatriste Gonzalez, Kai Xu, Peter D. Nagy

Plant Pathology Faculty Publications

Positive-strand RNA viruses assemble numerous membrane-bound viral replicase complexes within large replication compartments to support their replication in infected cells. Yet the detailed mechanism of how given subcellular compartments are subverted by viruses is incompletely understood. Although, Tomato bushy stunt virus (TBSV) uses peroxisomal membranes for replication, in this paper, we show evidence that the ER-resident SNARE (soluble NSF attachment protein receptor) proteins play critical roles in the formation of active replicase complexes in yeast model host and in plants. Depletion of the syntaxin 18-like Ufe1 and Use1, which are components of the ER SNARE complex in the ERAS (ER ...


Roles Of Phospholipases And Ribosomal S6 Kinase In Lipid Remodeling And Growth In Arabidopsis Response To Phosphate Deprivation, Yuan Su Apr 2018

Roles Of Phospholipases And Ribosomal S6 Kinase In Lipid Remodeling And Growth In Arabidopsis Response To Phosphate Deprivation, Yuan Su

Dissertations

Phosphate (Pi) is one of three macronutrients for plants, which is vital for plant growth and development. Understanding the mechanism by which plants respond and adapt to Pi deficiency not only unveils functions of genes and pathways involved, but also provides potential tools to manipulate crops to better stand Pi stress in low Pi-containing lands. One of the significant metabolic changes in plants under Pi starvation is the membrane lipid remodeling that converts Pi-containing lipids such as phospholipids to Pi-free lipids, such as glycolipids. To elucidate the metabolism and regulation of lipid remodeling, this dissertation characterizes the role of two ...


Constitutive Expression Of Thioglucoside Glucohydrolase 1 (Tgg1) Decreases Intercellular Trafficking In Arabidopsis Thaliana, Alessandro Francesco Sarno Apr 2018

Constitutive Expression Of Thioglucoside Glucohydrolase 1 (Tgg1) Decreases Intercellular Trafficking In Arabidopsis Thaliana, Alessandro Francesco Sarno

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Plasmodesmata (PD) are pores that traverse plant cell walls, providing a route for intercellular trafficking of essential metabolites, nutrients, and signaling molecules between adjacent plant cells, thereby aiding communication. The increased size exclusion limit 2 (ise2) mutant of Arabidopsis thaliana has an increased abundance of branched PD, as well as a greater flux of intercellular trafficking. A search for proteins that interact with ISE2 identified THIOGLUCOSIDE GLUCOHYDROLASE 2 (a myrosinase). A. thaliana also encodes a second, closely-related myrosinase, TGG1. Myrosinases are enzymes that catalyze the hydrolysis of glucosinolates, a type of secondary metabolite that are amino acid derivatives. The breakdown ...


Light Regulates The Rubylation Levels Of Individual Cullin Proteins In Arabidopsis Thaliana, Matthew J. Christians, Aron Rottier, Carly Wiersma Feb 2018

Light Regulates The Rubylation Levels Of Individual Cullin Proteins In Arabidopsis Thaliana, Matthew J. Christians, Aron Rottier, Carly Wiersma

Funded Articles

In plants, the small protein related to ubiquitin (RUB) modifies cullin (CUL) proteins in ubiquitin E3 ligases to allow for efficient transfer of ubiquitin to substrate proteins for degradation by the 26S proteasome. At the molecular level, the conjugation of RUB to individual CUL proteins is transient in nature, which aids in the stability of the cullins and adaptor proteins. Many changes in cellular processes occur within the plant upon exposure to light, including well-documented changes in the stability of individual proteins. However, overall activity of E3 ligases between dark- and light-grown seedlings has not been assessed in plants. In ...


Dynamics Of Autophagosome Formation, Junmarie Soto-Burgos, Xiaohong Zhuang, Liwen Jiang, Diane C. Bassham Jan 2018

Dynamics Of Autophagosome Formation, Junmarie Soto-Burgos, Xiaohong Zhuang, Liwen Jiang, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Autophagy, literally defined as “self-eating,” functions as a degradation process by recycling cytoplasmic contents under stress conditions or during development. Upon activation of autophagy, a membrane structure known as a phagophore forms and expands, finally closing to form a double-membrane vesicle called an autophagosome (Fig. 1; Lamb et al., 2013; Yin et al., 2016). The completed autophagosome, which contains the autophagic cargo, is delivered to the vacuole (plants and yeast) or lysosome (animals). The outer membrane fuses with the vacuolar/lysosomal membrane, and the inner membrane and contents are released into the vacuole/lysosome as an autophagic body and are ...


Cellular Dynamics: Cellular Systems In The Time Domain, Dan Szymanski, Diane Bassham, Teun Munnik, Wataru Sakamoto Jan 2018

Cellular Dynamics: Cellular Systems In The Time Domain, Dan Szymanski, Diane Bassham, Teun Munnik, Wataru Sakamoto

Genetics, Development and Cell Biology Publications

Plant cells are the fundamental building blocks of growth and development. For each cell type, the size, shape, and mechanical properties of the cell wall are customized for particular physiological functions (Szymanski and Cosgrove, 2009; Winship et al., 2011). The morphogenesis of highly polarized cell types such as trichoblasts and pollen tubes is internally programmed and occurs largely in the absence of a neighbor. Most cell types differentiate in the context of a tissue. Therefore, their growth and shape change can operate at larger spatial scales to influence tissue- and organ-level processes. Because plant cells grow symplastically and are mechanically ...


Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase Jan 2018

Investigating Phosphorylation Patterns And Their Effect On The Activity Of Transcription Factor Taabf1 In Imbibing Cereal Grains, Grace Uwase

Honors Theses

The wheat transcription factor TaABF1 plays an important role in hormone-mediated regulation of seed dormancy and germination of cereal grains. Evidence shows that TaABF1 activity is regulated by phosphorylation, and previous work in our lab showed that when serine residues in its conserved regions; S36, S37, S113, S115 were altered to phosphomimetic aspartate, the 4xD TaABF1 mutant had increased activity as a transcription factor. However, when only S113 was altered, TaABF1’s activity was greatly reduced. The work presented here explored whether the S36D/S37D/S115D mutant would have stronger activity than the 4xD mutant. Using the particle bombardment technique ...


Characterization Of A Novel Vps26c-Retromer Complex And Its Interaction With An Endosomal Trafficking Pathway Regulated By The Snare Vti13 In Controlling Polarized Growth And Cell Wall Organization In Arabidopsis Thaliana, Suryatapa Ghosh Jha Jan 2018

Characterization Of A Novel Vps26c-Retromer Complex And Its Interaction With An Endosomal Trafficking Pathway Regulated By The Snare Vti13 In Controlling Polarized Growth And Cell Wall Organization In Arabidopsis Thaliana, Suryatapa Ghosh Jha

Graduate College Dissertations and Theses

The endosomal trafficking system is a network of highly coordinated cellular pathways that control the growth and function of cells. The coordination of secretion and endocytosis in cells is one of the primary drivers of polarized growth, where new plasma membrane and cell wall components are deposited at the growing apex. In plants, one of the cell types exhibiting polarized growth are the root hairs. Root hairs are regulated extensions of epidermal cells called trichoblasts and are essential for anchorage, absorption of water and nutrients, and plant-microbe interactions. In this thesis, I characterize a previously undescribed protein involved in retromer ...


The Interplay Between Polarity Regulators, Calcium, And The Actin Cytoskeleton During Tip Growth, Carlisle Bascom Jr Jan 2018

The Interplay Between Polarity Regulators, Calcium, And The Actin Cytoskeleton During Tip Growth, Carlisle Bascom Jr

Doctoral Dissertations

Plant cell growth is a meticulously regulated process whereby the cell wall is selectively loosened to allow for turgor-pressure driven expansion. The rate of expansion must equal delivery of new material, or the cell will lyse. In many plant cells, this process happens diffusely around the cell. However, a number of plant cells have anisotropic shapes that require exquisite spatial control of secretion. One simple example of anisotropic patterning is tip growth; highly polarized cell expansion utilized by pollen tubes, root hairs, and moss protonemata. Investigating the role various molecules have in tip growth sheds light on how plant cells ...


Characterization Of Glyphosate-Resistant Amaranthus Palmeri (Palmer Amaranth) Tolerance To Als- And Hppd-Inhibiting Herbicides, Shilpa Singh Dec 2017

Characterization Of Glyphosate-Resistant Amaranthus Palmeri (Palmer Amaranth) Tolerance To Als- And Hppd-Inhibiting Herbicides, Shilpa Singh

Theses and Dissertations

Palmer amaranth is a principal weed problem across the United States and is resistant to several herbicide modes of action. By 2008, Palmer amaranth in Arkansas was reported to be resistant to both ALS- and EPSPS-inhibitors, but the predominant resistance mechanisms are yet to be explored. Herbicide options with different modes of action are needed to provide effective Palmer amaranth control and HPPD-inhibitors (e.g. mesotrione) are among these. The goal of this research was to elucidate the resistance profile of Palmer amaranth in Arkansas to ALS herbicides and glyphosate (EPSPS-inhibitor) as well as evaluate the differential tolerance of Palmer ...


Investigation Of Moringa Oleifera Leaf Extract And Its Cancer-Selective Antiproliferative Properties, Reagen H. Welch, Ashlee H. Tietje Nov 2017

Investigation Of Moringa Oleifera Leaf Extract And Its Cancer-Selective Antiproliferative Properties, Reagen H. Welch, Ashlee H. Tietje

Journal of the South Carolina Academy of Science

Moringa oleifera is a tree native to a number of Asian, African, and Central American countries and has been used in traditional medicine for an assortment of medicinal uses for centuries. Due to bioactive compounds within Moringa leaves, it is believed that Moringa leaf extract may possess cancer-selective antiproliferative properties. Previous research has been conducted in regards to this topic, but poor experimental design due to lack of necessary controls limits the legitimacy of anticancer claims. While previous research has shown that Moringa leaf extract has the potential to kill cancer cells, the research fails to demonstrate the effects of ...


Characterization Of Acaricide Resistance, Plant-Mediated Rnai Against Two-Spotted Spider Mites (Tetranychus Urticae Koch), And Assessing Off- And Non-Target Effects, Hooman Hosseinzadeh Namin Oct 2017

Characterization Of Acaricide Resistance, Plant-Mediated Rnai Against Two-Spotted Spider Mites (Tetranychus Urticae Koch), And Assessing Off- And Non-Target Effects, Hooman Hosseinzadeh Namin

Electronic Thesis and Dissertation Repository

The two-spotted spider mite (TSSM), Tetranychus urticae (Koch), is one of the most damaging agricultural pests in the world. It feeds on over 150 crops, causing considerable yield losses in greenhouses and agricultural fields. Currently, using synthetic acaricides is the main method to control TSSM. However, it can develop resistance to acaricides with repeated exposure, and typically resistance can occur within two to four years. To understand the underlying mechanisms of spider mite adaptation to acaricides is an essential part of resistance management strategy. The resistance ratio of the pyridaben-selected strain compared with the pre-selection strain was estimated at greater ...


The Effect Of Diet On Midgut And Resulting Changes In Infectiousness Of Acmnpv Baculovirus In Trichoplusia Ni, Elizabeth Chen Sep 2017

The Effect Of Diet On Midgut And Resulting Changes In Infectiousness Of Acmnpv Baculovirus In Trichoplusia Ni, Elizabeth Chen

Electronic Thesis and Dissertation Repository

The cabbage looper, Trichoplusia ni, a global generalist lepidopteran pest, has developed resistance to many synthetic and biological insecticides, requiring effective and environmentally acceptable alternatives. One possibility is the Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV). This baculovirus is highly infectious for T. ni, with potential as a biocontrol agent, however, its effectiveness is strongly influenced by dietary context. In this study, microscopy and transcriptomics were used to examine how the efficacy of this virus was affected when T. ni larvae were raised on different diets. Larvae raised on potato host plants had lower chitinase and chitin deacetylase transcript levels and thickened ...


Materials And Method For Modifying A Biochemical Component In A Plant, Ling Li, Eve Syrkin Wurtele Aug 2017

Materials And Method For Modifying A Biochemical Component In A Plant, Ling Li, Eve Syrkin Wurtele

Ling Li

A method of modifying the amount of at least one biochemical component in a plant comprising expressing Qua-Quine Starch (QQS) in the plant, the wild-type of which does not express QQS; a transgenic plant, or part thereof, which comprises and expresses QQS as a transgene and in which the amount of at least one biochemical component is modified; a tissue culture of regenerable cells of the transgenic plant; a vector comprising a nucleotide sequence, which encodes the coding sequence of QQS, operably linked to a non-native promoter, which promotes expression of the nucleotide sequence in a plant, which is other ...


The Qqs Orphan Gene Of Arabidopsis Modulates Carbon And Nitrogen Allocation In Soybean, Ling Li, Eve S. Wurtele Aug 2017

The Qqs Orphan Gene Of Arabidopsis Modulates Carbon And Nitrogen Allocation In Soybean, Ling Li, Eve S. Wurtele

Ling Li

The genome of each species contains as high as 8% of genes that are uniquely present in that species. Little is known about the functional significance of these so-called species specific or orphan genes. The Arabidopsis thaliana gene Qua-Quine Starch (QQS) is species specific. Here, we show that altering QQS expression in Arabidopsis affects carbon partitioning to both starch and protein. We hypothesized QQS may be conserved in a feature other than primary sequence, and as such could function to impact composition in another species. To test the potential of QQS in affecting composition in an ectopic species, we introduced ...


Snrk1 Activates Autophagy Via The Tor Signaling Pathway In Arabidopsis Thaliana, Junmarie Soto-Burgos, Diane C. Bassham Aug 2017

Snrk1 Activates Autophagy Via The Tor Signaling Pathway In Arabidopsis Thaliana, Junmarie Soto-Burgos, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Autophagy is a degradation process in which cells break down and recycle their cytoplasmic contents when subjected to environmental stress or during cellular remodeling. The Arabidopsis thaliana SnRK1 complex is a protein kinase that senses changes in energy levels and triggers downstream responses to enable survival. Its mammalian ortholog, AMPK, and yeast ortholog, Snf-1, activate autophagy in response to low energy conditions. We therefore hypothesized that SnRK1 may play a role in the regulation of autophagy in response to nutrient or energy deficiency in Arabidopsis. To test this hypothesis, we determined the effect of overexpression or knockout of the SnRK1 ...


Tor-Dependent And -Independent Pathways Regulate Autophagy In Arabidopsis Thaliana, Yunting Pu, Xinjuan Luo, Diane C. Bassham Jul 2017

Tor-Dependent And -Independent Pathways Regulate Autophagy In Arabidopsis Thaliana, Yunting Pu, Xinjuan Luo, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Autophagy is a critical process for recycling of cytoplasmic materials during environmental stress, senescence and cellular remodeling. It is upregulated under a wide range of abiotic stress conditions and is important for stress tolerance. Autophagy is repressed by the protein kinase target of rapamycin (TOR), which is activated in response to nutrients and in turn upregulates cell growth and translation and inhibits autophagy. Down-regulation of TOR in Arabidopsis thaliana leads to constitutive autophagy and to decreased growth, but the relationship to stress conditions is unclear. Here, we assess the extent to which TOR controls autophagy activation by abiotic stress. Overexpression ...


Myosin Xi-I Works In Tandem With A Microtubule-Associated Mechanism To Position The Nucleus In Arabidopsis Root Hairs, Ian Andrew Windham May 2017

Myosin Xi-I Works In Tandem With A Microtubule-Associated Mechanism To Position The Nucleus In Arabidopsis Root Hairs, Ian Andrew Windham

Chancellor’s Honors Program Projects

No abstract provided.


Selective Autophagy Of Bes1 Mediated By Dsk2 Balances Plant Growth And Survival, Trevor M. Nolan, Benjamin Brennan, Mengran Yang, Jiani Chen, Mingcai Zhang, Zhaohu Li, Xuelu Wang, Diane C. Bassham, Justin Walley, Yanhai Yin Apr 2017

Selective Autophagy Of Bes1 Mediated By Dsk2 Balances Plant Growth And Survival, Trevor M. Nolan, Benjamin Brennan, Mengran Yang, Jiani Chen, Mingcai Zhang, Zhaohu Li, Xuelu Wang, Diane C. Bassham, Justin Walley, Yanhai Yin

Genetics, Development and Cell Biology Publications

Plants encounter a variety of stresses and must fine-tune their growth and stress-response programs to best suit their environment. BES1 functions as a master regulator in the brassinosteroid (BR) pathway that promotes plant growth. Here, we show that BES1 interacts with the ubiquitin receptor protein DSK2 and is targeted to the autophagy pathway during stress via the interaction of DSK2 with ATG8, a ubiquitin-like protein directing autophagosome formation and cargo recruitment. Additionally, DSK2 is phosphorylated by the GSK3-like kinase BIN2, a negative regulator in the BR pathway. BIN2 phosphorylation of DSK2 flanking its ATG8 interacting motifs (AIMs) promotes DSK2-ATG8 interaction ...


Tno1, A Tgn-Localized Snare-Interacting Protein, Modulates Root Skewing In Arabidopsis Thaliana, Rahul Roy, Diane C. Bassham Jan 2017

Tno1, A Tgn-Localized Snare-Interacting Protein, Modulates Root Skewing In Arabidopsis Thaliana, Rahul Roy, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Background: The movement of plant roots within the soil is key to their ability to interact with the environment and maximize anchorage and nutrient acquisition. Directional growth of roots occurs by a combination of sensing external cues, hormonal signaling and cytoskeletal changes in the root cells. Roots growing on slanted, impenetrable growth medium display a characteristic waving and skewing, and mutants with deviations in these phenotypes assist in identifying genes required for root movement. Our study identifies a role for a trans-Golgi network-localized protein in root skewing.

Results: We found that Arabidopsis thaliana TNO1 (TGN-localized SYP41-interacting protein), a putative tethering ...


The Key Question In Symbiotic Nitrogen Fixation: How Does Host Maintain A Bacterial Symbiont?, Onur Oztas Jan 2017

The Key Question In Symbiotic Nitrogen Fixation: How Does Host Maintain A Bacterial Symbiont?, Onur Oztas

Doctoral Dissertations

The fact that plants cannot use nitrogen in the gaseous form makes them dependent on the levels of usable nitrogen forms in the soil. Legumes overcome nitrogen limitation by entering a symbiotic association with rhizobia, soil bacteria that convert atmospheric nitrogen into usable ammonia. In root nodules, bacteria are internalized by host plant cells inside an intracellular compartment called the symbiosome where they morphologically differentiate into nitrogen-fixing forms by symbiosome-secreted host proteins.

In this project, I explained the host proteins required to maintain bacterial symbionts and described their delivery to the symbiosome. I showed that the SYNTAXIN 132 (SYP132) gene ...