Open Access. Powered by Scholars. Published by Universities.®

Molecular Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 13 of 13

Full-Text Articles in Molecular Biology

Molecular Mechanisms Governing Plant Parasitic Nematode Signaling And Host Parasitism, Stacey Nicola Barnes Jan 2018

Molecular Mechanisms Governing Plant Parasitic Nematode Signaling And Host Parasitism, Stacey Nicola Barnes

Graduate Theses and Dissertations

Pathogen infection of crops causes large-scale annual yield losses for farmers worldwide and hinders global efforts to provide adequate amounts of nutrition for the ever-growing human population. Plant-parasitic nematodes (PPN) are among some of the most devastating pathogens due to their ability to parasitize an expansive variety of agriculturally important crops. In order to identify ways to attenuate PPN infection and limit yield losses it is vital that we increase our understanding of host-PPN interactions. Here we investigate the molecular mechanisms that are occurring both within PPN and at the interface between PPN and their host plants.

Research into PPN-derived ...


Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew Jan 2018

Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew

Graduate Theses and Dissertations

Soybean sudden death syndrome (SDS) is one of the most important soybean diseases in the Midwestern United States, leading to average losses of $396 million per year from 1996 to 2015. The causal agent of SDS, soilborne fungus Fusarium virguliforme (Fv), causes root rot symptoms and releases phytotoxins taken up by the plant to produce chlorosis and necrosis in the leaves. The main management practice used to reduce the impact of SDS is planting resistant soybean cultivars. Resistance to SDS is known to be quantitative with 88 known quantitative trait loci (QTL) based on Soybase.org. Many of these QTL ...


Investigations Into Nutritional Quality, Commercial Productivity, And Genetic Purity Of Maize Grain For Organic Production Systems, Ryan Huffman Jan 2017

Investigations Into Nutritional Quality, Commercial Productivity, And Genetic Purity Of Maize Grain For Organic Production Systems, Ryan Huffman

Graduate Theses and Dissertations

Consumer demand for organic maize grain has steadily increased in the past decade which has resulted in an increased interest for this market class by plant breeders and geneticist. Each chapter in this dissertation investigates areas of concern to the organic community and possible solutions for improvement. Chapter 2 seeks to understand which combinations of genetic mechanisms are capable of a further increase in the methionine concentration of maize grain over individual mechanisms. Based on the genetic mechanisms evaluated, it was concluded that crosses combining dzr1 and recurrent selection in hybrid combination can elevate methionine concentration and overall grain nutritional ...


Analysis Of The Induction Of Autophagy During Er Stress And The Vesicle Fusion Machinery At The Trans-Golgi Network In Arabidopsis Thaliana, Xiaochen Yang Jan 2016

Analysis Of The Induction Of Autophagy During Er Stress And The Vesicle Fusion Machinery At The Trans-Golgi Network In Arabidopsis Thaliana, Xiaochen Yang

Graduate Theses and Dissertations

The vacuole in plant cells occupies more than 80% of the cellular volume and is involved in development, detoxification, and degradation of proteins. In this dissertation, I focused on the two vesicle trafficking pathways, autophagy and vacuolar trafficking, which deliver cellular components to the vacuole.

Autophagy is an evolutionarily conserved mechanism in eukaryotic cells for degradation and recycling of cytoplasmic materials and damaged cell components during development or upon encountering stress conditions. Previous studies showed that autophagy is activated by endoplasmic reticulum (ER) stress and delivers ER fragments to the vacuole. ER stress is defined as accumulation of unfolded or ...


Host Target Genes Of The Xanthomonas Oryzae Pv. Oryzae Type Iii Effectors For Bacterial Blight In Rice, Junhui Zhou Jan 2015

Host Target Genes Of The Xanthomonas Oryzae Pv. Oryzae Type Iii Effectors For Bacterial Blight In Rice, Junhui Zhou

Graduate Theses and Dissertations

Xanthomonas oryzae pv. oryzae is the causal agent of the bacterial blight in rice, which invades the host rice plant through injecting a myriad of effector proteins through a structure called type Ⅲ secretion system, thereafter, these effectors are also called type Ⅲ effectors. There are two groups of type Ⅲ effectors: TAL (Transcription Activator-Like) effectors that specifically bind to the promoter region of particular host genes and regulate host gene transcription and Non-TAL effectors that bind to host gene products and manipulate the host immune system.

In this thesis, I present the work of three projects. First, I, and ...


The Molecular Mechanisms Of Brassinosteroid-Regulated Drought Stress Response In Arabidopsis Thaliana, Buyun Tang Jan 2015

The Molecular Mechanisms Of Brassinosteroid-Regulated Drought Stress Response In Arabidopsis Thaliana, Buyun Tang

Graduate Theses and Dissertations

Brassinosteroids (BRs) are involved in diverse developmental processes such as cell elongation, vascular differentiation, senescence and stress response. The mechanisms and regulatory networks of BR-regulated plant growth and development have been well described for the past decade with the identification of receptors, kinases and central transcription factors involved in BR signaling. Recent studies revealed BRs also extensively participated in plant response to environmental stresses, although the mechanisms of BR-regulated stress response is largely unknown. Coordination of plant growth and stress response requires integration of multiple signaling output through hormonal crosstalk. Studies of BR signaling pathway and BR-mediated physiological responses indicate ...


Ribosomal Frameshifting Directed By A Potyvirid Sequence Motif In Diverse Translation Systems, Alice Y. Hui Jan 2015

Ribosomal Frameshifting Directed By A Potyvirid Sequence Motif In Diverse Translation Systems, Alice Y. Hui

Graduate Theses and Dissertations

The family, Potyviridae, contains a third of all known plant viruses within eight genera. The genome is translated as one large polyprotein from which ten mature proteins are proteolytically cleaved. Recently, discovery of a protein translated from an overlapping reading frame (pipo) proved essential in systemic plant infection. It is hypothesized to translate via a ribosomal frameshift, change in reading frame during the elongation phase of translation. The cryptic programmed ribosomal frameshift signal had been undetected until now because it lacks the canonical characteristics: slippery sequence, spacer sequence, and RNA secondary structure, in that order. Only one of the three ...


Mobile Mrna: A Long Distance Signaling System In Potato, Tian Lin Jan 2014

Mobile Mrna: A Long Distance Signaling System In Potato, Tian Lin

Graduate Theses and Dissertations

Mobile mRNA is one of the most important long-distance signals in plant vascular system. They play important roles in responding to environmental cues, such as photoperiod. There are numerous studies on mobile mRNAs in plants and thousand of mRNAs have been detected in phloem sap. One of the BEL1-like genes, designated StBEL5, has transcripts that move long distance from leaf to stolon tips and enhance tuberization. However, not many mobile mRNAs have been characterized. The mechanism of the long-distance movement of mRNAs is not clear. In this dissertation, we conducted research on different levels to characterize known mobile mRNA and ...


Hybrid Breeding In Perennial Grasses Based On Self-Incompatibility And Self-Fertility, Andrea Sofia Arias Aguirre Jan 2013

Hybrid Breeding In Perennial Grasses Based On Self-Incompatibility And Self-Fertility, Andrea Sofia Arias Aguirre

Graduate Theses and Dissertations

For a long time, petroleum-based fuels have been used to provide energy, but limited supplies along with environmental effects of fossil fuels created the need of alternative and clean energy sources. Grasses in general have a low lignin content compared to woody species which is desirable for ethanol production. Furthermore, other features such as: low water and nutrient requirements, and a high rate of carbon fixation that make grasses desirable for biomass production. Perennial grasses have also environmental advantages such as reduced soil organic matter and tillage requirements compared with annual species. Perennial ryegrass has been increasingly used in Europe ...


Investigation Of The Arabidopsis Nonhost Resistance Mechanism Against The Soybean Pathogen, Phytophthora Sojae, Rishi Sumit Jan 2013

Investigation Of The Arabidopsis Nonhost Resistance Mechanism Against The Soybean Pathogen, Phytophthora Sojae, Rishi Sumit

Graduate Theses and Dissertations

Nonhost resistance (NHR) provides immunity to all members of a plant species against all isolates of a microorganism that is pathogenic to other plant species. Three Arabidopsis thaliana PEN (penetration deficient) genes, PEN1, 2 and 3 have been shown to provide prehaustorial NHR against the barley pathogen Blumeria graminis f. sp. hordei. Arabidopsis pen1-1 mutant is penetrated by the hemibiotrophic oomycete pathogen, Phytophthora sojae that causes root and stem rot disease in soybean. The P. sojae susceptible (pss) 1 mutant is infected by both P. sojae and the hemibiotrophic fungal pathogen, Fusarium virguliforme that causes sudden death syndrome in soybean ...


Systematics Of Harrisia (Cactaceae), Alan R. Franck Jan 2012

Systematics Of Harrisia (Cactaceae), Alan R. Franck

Graduate Theses and Dissertations

The genus Harrisia Britton (Cactaceae) comprises species of columnar cacti that are united by a unique seed morphology. The species range in form from prostrate shrubs to large trees and are native to South America and the Caribbean region. Harrisia is placed in an unresolved position within subtribe Trichocereinae of tribe Cereeae of subfamily Cactoideae. Relationships among the species within Harrisia are also poorly understood. In this study, several species of Harrisia were sequenced for as many as seven different regions of nuclear and plastid DNA. Species in the Caribbean were also examined with amplified fragment length polymorphisms. The morphology ...


Strategies For Recombinant Protein Production In Maize, Xing Xu Jan 2012

Strategies For Recombinant Protein Production In Maize, Xing Xu

Graduate Theses and Dissertations

Maize is not only one of the world's most important crops, but it is also the first field-grown plant-based recombinant expression system developed for commercial purposes. With advantages of low cost, high yield, high protein stability, and well-developed transformation technology over other plant systems, maize is considered to be an ideal recombinant production system. However, there are three major challenges limiting the use of maize for producing recombinant proteins: 1) maize lacks mammalian-like post-translational modification ability that may be required for pharmaceutical and industrial proteins; 2) transgenic pollen containment in open-field production; and 3) low expression of recombinant products ...


Evaluation Of Polypyrimidine Tract-Binding Protein Gene Promoters In Potato (Solanum Tuberosum Cv. Désirée), Nathaniel Martin Butler Jan 2012

Evaluation Of Polypyrimidine Tract-Binding Protein Gene Promoters In Potato (Solanum Tuberosum Cv. Désirée), Nathaniel Martin Butler

Graduate Theses and Dissertations

Polypyrimidine tract-binding (PTB) proteins are RNA-binding proteins that target specific RNAs for post-transcriptional processing by binding CU-rich motifs. PTBs have established functions in a range of RNA processes including splicing, translation, stability, and long-distance transport. Six PTB-like genes identified in potato have been grouped into two clades based on homology to other known plant PTBs. StPTB1 and StPTB6 are closely related to a PTB protein discovered in pumpkin, designated CmRBP50, and contain four canonical RNA-recognition motifs. CmRBP50 is expressed in phloem tissues and functions as the core protein of a phloem-mobile RNA/protein complex. Sequence from the potato genome database ...