Plant Breeding and Genetics Commons^™

Mac3a And Mac3b, Two Core Subunits Of The Mos4-Associated Complex, Positively Influence Mirna Biogenesis, Shengjun Li, Kan Liu, Bangjun Zhou, Mu Li, Shuxin Zhang, Lirong Zeng, Chi Zhang, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MAC3A and MAC3B are conserved U-box containing proteins in eukaryotes. They are subunits of the MOS4-associated complex (MAC) that plays essential roles in plant immunity and development in Arabidopsis. However, their functional mechanisms remain elusive. Here we show that Arabidopsis thaliana MAC3A and MAC3B act redundantly in microRNA (miRNA) biogenesis. Lack of both MAC3A and MAC3B in the mac3b mac3b double mutant reduces the accumulation of miRNAs, causing elevated transcript levels of miRNA targets. mac3a mac3b also decreases the levels of primary miRNA transcripts (pri-miRNAs). However, MAC3A and MAC3B do not affect the promoter activity of genes encoding miRNAs ( …

Resistance In 27 Rice Cultivars To Sugarcane Borer (Lepidoptera: Crambidae), F. Correa, C. L. T. Silva, A. P. Pelosi, A. C. S. Almeida, E. A. Heinrichs, J. A. F. Barrigossi, F. G. Jesus

Department of Entomology: Faculty Publications

Rice (Oryza sativa L.) is considered one of the most important crops in the world, and the sugarcane borer, Diatraea saccharalis Fabricius (Lepidoptera: Crambidae), is among the key pests damaging the crop in the Americas. The objective of this work was to identify rice genotypes as a source of resistance to D. saccharalis. Rice plants were infested in the greenhouse and subsequently evaluated for damage, larval weight and survival, and stem size. The cultivars “Bonança,” “Caripuna,” “IR 42,” “Canela de Ferro,” “SWA Norte,” “BR IRGA 409,” “Pepita,” “Serra Dourada,” “Araguaia,” “Xingú,” “Tangará,” and “Soberana” showed antibiosis, antixenosis, or …

Gene Flow From Single And Stacked Herbicide-Resistant Rice (Oryza Sativa): Modeling Occurrence Of Multiple Herbicide-Resistant Weedy Rice, Joseph Dauer, Andrew Hulting, Dale Carlson, Luke Mankin, John Harden, Carol Mallory-Smith

School of Natural Resources: Faculty Publications

Background: Provisia™ rice (PV), a non-genetically engineered (GE) quizalofop-resistant rice, will provide growers with an additional option for weed management to use in conjunction with Clearfield® rice (CL) production. Modeling compared the impact of stacking resistance traits versus single traits in rice on introgression of the resistance trait to weedy rice (also called red rice). Common weed management practices were applied to 2-, 3- and 4-year crop rotations, and resistant and multiple-resistant weedy rice seeds, seedlings and mature plants were tracked for 15 years.

Results: Two-year crop rotations resulted in resistant weedy rice after 2 years with abundant populations (exceeding …

Development Of Ifox-Hunting As A Functional Genomic Tool And Demonstration Of Its Use To Identify Early Senescence-Related Genes In The Polyploid Brassica Napus, Juan Ling, Renjie Li, Chinedu Charles Nwafor, Junluo Cheng, Maoteng Li, Qing Xi, Jian Wu, Lu Gan, Qingyong Yang, Chao Liu, Ming Chen, Yongming Zhou, Edgar B. Cahoon, Chunyu Zhang

Center for Plant Science Innovation: Faculty Publications

Functional genomic studies of many polyploid crops, including rapeseed (Brassica napus), are constrained by limited tool sets. Here we report development of a gain-of-function platform, termed ‘iFOX (inducible Full-length cDNA OvereXpressor gene)-Hunting’, for inducible expression of B. napus seed cDNAs in Arabidopsis. A Gateway-compatible plant gene expression vector containing a methoxyfenozide-inducible constitutive promoter for transgene expression was developed. This vector was used for cloning of random cDNAs from developing B. napus seeds and subsequent Agrobacterium-mediated transformation of Arabidopsis. The inducible promoter of this vector enabled identification of genes upon induction that are otherwise lethal when constitutively overexpressed and …

Conventional And Hyperspectral Time-Series Imaging Of Maize Lines Widely Used In Field Trials, Zhikai Liang, Piyush Pandey, Vincent Stoerger, Yuhang Xu, Yumou Qiu, Yufeng Ge, James C. Schnable

Center for Plant Science Innovation: Faculty Publications

Background: Maize (Zea mays ssp. mays) is 1 of 3 crops, along with rice and wheat, responsible for more than one-half of all calories consumed around the world. Increasing the yield and stress tolerance of these crops is essential to meet the growing need for food. The cost and speed of plant phenotyping are currently the largest constraints on plant breeding efforts. Datasets linking new types of high-throughput phenotyping data collected from plants to the performance of the same genotypes under agronomic conditions across a wide range of environments are essential for developing new statistical approaches and computer …

Single-Molecule Sequencing And Optical Mapping Yields An Improved Genome Of Woodland Strawberry (Fragaria Vesca) With Chromosome-Scale Contiguity, Patrick P. Edger, Robert Vanburen, Marivi Colle, Thomas J. Poorten, Ching Man Wai, Chad E. Niederhuth, Elizabeth I. Alger, Shujun Ou, Charlotte B. Acharya, Jie Wang, Pete Callow, Michael R. Mckain, Jinghua Shi, Chad Collier, Zhiyong Xiong, Jeffrey P. Mower, Janet P. Slovin, Timo Hytonen, Ning Jiang, Kevin L. Childs, Steven J. Knapp

Center for Plant Science Innovation: Faculty Publications

Background: Although draft genomes are available for most agronomically important plant species, the majority are incomplete, highly fragmented, and often riddled with assembly and scaffolding errors. These assembly issues hinder advances in tool development for functional genomics and systems biology. Findings: Here we utilized a robust, cost-effective approach to produce high-quality reference genomes.We report a near-complete genome of diploid woodland strawberry (Fragaria vesca) using single-molecule real-time sequencing from Pacific Biosciences (PacBio). This assembly has a contig N50 length of ~7.9 million base pairs (Mb), representing a ~300-fold improvement of the previous version. The vast majority (>99.8%) …

Identification Of Bottlenecks In The Accumulation Of Cyclic Fatty Acids In Camelina Seed Oil, Xiao-Hong Yu, Rebecca E. Cahoon, Patrick J. Horn, Hai Shi, Richa R. Prakash, Yuanheng Cai, Maegan Hearney, Kent D. Chapman, Edgar B. Cahoon, Jorg Schwender, John Shanklin

Center for Plant Science Innovation: Faculty Publications

Modified fatty acids (mFA) have diverse uses; for example, cyclopropane fatty acids (CPA) are feedstocks for producing coatings, lubricants, plastics and cosmetics. The expression of mFA-producing enzymes in crop and model plants generally results in lower levels of mFA accumulation than in their natural-occurring source plants. Thus, to further our understanding of metabolic bottlenecks that limit mFA accumulation, we generated transgenic Camelina sativa lines co-expressing Escherichia coli cyclopropane synthase (EcCPS) and Sterculia foetida lysophosphatidic acid acyltransferase (SfLPAT). In contrast to transgenic CPA-accumulating Arabidopsis, CPA accumulation in camelina caused only minor changes in seed weight, germination rate, oil accumulation and seedling …

Integrating Phylogenetic And Network Approaches To Study Gene Family Evolution: The Case Of The Agamous Family Of Floral Genes, Daniel Santana De Carvalho, James C. Schnable, Ana Maria R. Almeida

Center for Plant Science Innovation: Faculty Publications

The study of gene family evolution has benefited from the use of phylogenetic tools, which can greatly inform studies of both relationships within gene families and functional divergence. Here, we propose the use of a network-based approach that in combination with phylogenetic methods can provide additional support for models of gene family evolution. We dissect the contributions of each method to the improved understanding of relationships and functions within the well-characterized family of AGAMOUS floral development genes. The results obtained with the two methods largely agreed with one another. In particular, we show how network approaches can provide improved interpretations …

Functional Modeling Of Plant Growth Dynamics, Y. Xu, Y. Qiu, James C. Schnable

Center for Plant Science Innovation: Faculty Publications

Recent advances in automated plant phenotyping have enabled the collection of time series measurements from the same plants of a wide range of traits at different developmental time scales. The availability of time series phenotypic datasets has increased interest in statistical approaches for comparing patterns of change among different plant genotypes and different treatment conditions. Two widely used methods of modeling growth with time are pointwise analysis of variance (ANOVA) and parametric sigmoidal curve fitting. Pointwise ANOVA yields discontinuous growth curves, which do not reflect the true dynamics of growth patterns in plants. In contrast, fitting a parametric model to …

Gipc Glcnac Glycosyltransferase, Toshiki Ishikawa, Lin Fang, Emilie A. Rennie, Julien Sechet, Jingwei Yan, Beibei Jing, William Moore, Edgar B. Cahoon, Henrik V. Scheller, Maki Kawai-Yamada, Jenny C. Mortimer

Center for Plant Science Innovation: Faculty Publications

Glycosylinositol phosphorylceramides (GIPCs), which have a ceramide core linked to a glycan headgroup of varying structure, are the major sphingolipids in the plant plasma membrane. Recently, we identified the major biosynthetic genes for GIPC glycosylation in Arabidopsis thaliana, and demonstrated that the glycan headgroup is essential for plant viability. However, the function of GIPCs and the significance of their structural variation are poorly understood. Here, we characterized the Arabidopsis glycosyltransferase GLUCOSAMINE INOSITOLPHOSPHORYLCERAMIDE TRANSFERASE1 (GINT1) and showed that it is responsible for the glycosylation of a subgroup of GIPCs found in seeds and pollen that contain N-acetylglucosamine (GlcNAc) and glucosamine …

Sma1, A Homolog Of The Splicing Factor Prp28, Has A Multifaceted Role In Mirna Biogenesis In Arabidopsis, Shengjun Li, Ran Xu, Aixia Li, Kan Liu, Liqing Gu, Mu Li, Hairui Zhang, Yueying Zhang, Shangshang Zhuang, Quanhui Wang, Gang Gao, Na Li, Chi Zhang, Yunhai Li, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MicroRNAs (miRNAs) are a class of small non-coding RNAs that repress gene expression. In plants, the RNase III enzyme Dicer-like (DCL1) processes primary miRNAs (pri-miRNAs) into miRNAs. Here, we show that SMALL1 (SMA1), a homolog of the DEADbox pre-mRNA splicing factor Prp28, plays essential roles in miRNA biogenesis in Arabidopsis. A hypomorphic sma1-1 mutation causes growth defects and reduces miRNA accumulation correlated with increased target transcript levels. SMA1 interacts with the DCL1 complex and positively influences primiRNA processing. Moreover, SMA1 binds the promoter region of genes encoding pri-miRNAs (MIRs) and is required for MIR transcription. Furthermore, SMA1 also …

Generation And Evaluation Of Modified Opaque-2 Popcorn Suggests A Route To Quality Protein Popcorn, Ying Ren, Abou Yobi, Leandra Marshall, Ruthie Angelovici, Oscar Rodriguez, David R. Holding

Center for Plant Science Innovation: Faculty Publications

Introducing traits from dent corn to popcorn is challenging because it is difficult to recover adequate popping characteristics. QPM (Quality Protein Maize) is a dent corn variety carrying the opaque-2 (o2) mutation, specifying increased amounts of normally limiting essential amino acids, and modifier genes which restore the wild type vitreous kernel phenotype. In this study, we introgressed o2 and selected for endosperm modification using vitreousness and high 27-kD gamma zein content. In this way, we recovered high-lysine, fully poppable Quality Protein Popcorn (QPP). BC₂F₄ individuals with vitreous kernels were confirmed to be o2 mutants by …

Molecular Tools Enabling Pennycress (Thlaspi Arvense) As A Model Plant And Oilseed Cash Cover Crop, Michaela Mcginn, Winthrop B. Phippen, Ratan Chopra, Sunil Bansal, Brice A. Jarvis, Mary E. Phippen, Kevin M. Dorn, Maliheh Esfahanian, Tara J. Nazarenus, Edgar B. Cahoon, Timothy P. Durrett, M. David Marks, John C. Sedbrook

Center for Plant Science Innovation: Faculty Publications

Thlapsi arvense L. (pennycress) is being developed as a profitable oilseed cover crop for the winter fallow period throughout the temperate regions of the world, controlling soil erosion and nutrients run-off on otherwise barren farmland. We demonstrate that pennycress can serve as a user-friendly model system akin to Arabidopsis that is well-suited for both laboratory and field experimentation. We sequenced the diploid genome of the spring-type Spring 32-10 inbred line (1C DNA content of 539 Mb; 2n = 14), identifying variation that may explain phenotypic differences with winter-type pennycress, as well as predominantly a one-to-one correspondence with Arabidopsis genes, …

Lycophyte Plastid Genomics: Extreme Variation In Gc, Gene And Intron Content And Multiple Inversions Between A Direct And Inverted Orientation Of The Rrna Repeat, Jeffrey P. Mower, Peng-Fei Ma, Felix Grewe, Alex Taylor, Todd P. Michael, Robert Vanburen, Yin-Long Qiu

Center for Plant Science Innovation: Faculty Publications

Lycophytes are a key group for understanding vascular plant evolution. Lycophyte plastomes are highly distinct, indicating a dynamic evolutionary history, but detailed evaluation is hindered by the limited availability of sequences. Eight diverse plastomes were sequenced to assess variation in structure and functional content across lycophytes. Lycopodiaceae plastomes have remained largely unchanged compared with the common ancestor of land plants, whereas plastome evolution in Isoetes and especially Selaginella is highly dynamic. Selaginella plastomes have the highest GC content and fewest genes and introns of any photosynthetic land plant. Uniquely, the canonical inverted repeat was converted into a direct repeat (DR) …

The Role Of Type Iii Effectors From Xanthomonas Axonopodis Pv. Manihotis In Virulence And Suppression Of Plant Immunity, Cesar Augusto Medina, Paola Andrea Reyes, Cesar Augusto Trujillo, Juan Luis Gonzalez, David Alejandro Bejarano, Nathaly Andrea Montenegro, Jonathan M. Jacobs, Anna Joe, Silvia Restrepo, James R. Alfano, Adriana Bernal

Center for Plant Science Innovation: Faculty Publications

Xanthomonas axonopodis pv. manihotis (Xam) causes cassava bacterial blight, the most important bacterial disease of cassava. Xam, like other Xanthomonas species, requires type III effectors (T3Es) for maximal virulence. Xam strain CIO151 possesses 17 predicted T3Es belonging to the Xanthomonas outer protein (Xop) class. This work aimed to characterize nine Xop effectors present in Xam CIO151 for their role in virulence and modulation of plant immunity. Our findings demonstrate the importance of XopZ, XopX, XopAO1 and AvrBs2 for full virulence, as well as a redundant function in virulence between XopN and XopQ in susceptible cassava plants. We tested their role …

Xanthomonas Oryzae Pv. Oryzae Tale Proteins Recruit Ostfiiaγ1 To Compensate For The Absence Of Ostfiiaγ5 In Bacterial Blight In Rice, Wenxiu Ma, Lifang Zou, Zhiyuan Ji, Xiameng Xu, Zhengyin Xu, Yangyang Yang, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial blight (BB) of rice, uses transcription activator-like effectors (TALEs) to interact with the basal transcription factor gamma subunit OsTFIIAγ5 (Xa5) and activates the transcription of host genes. However, how OsTFIIAγ1, the other OsTFIIAγ protein, functions in the presence of TALEs remains unclear. In this study, we show that OsTFIIAγ1 plays a compensatory role in the absence of Xa5. The expression of OsTFIIAγ1, which is activated by TALE PthXo7, increases the expression of host genes targeted by avirulent and virulent TALEs. Defective OsTFIIAγ1 rice lines show reduced expression of the TALE-targeted …

Mac3a And Mac3b, Two Core Subunits Of The Mos4-Associated Complex, Positively Influence Mirna Biogenesis, Shengjun Li, Kan Liu, Bangjun Zhou, Mu Li, Shuxin Zhang, Lirong Zeng, Chi Zhang, Bin Yu

Center for Plant Science Innovation: Faculty Publications

MAC3A and MAC3B are conserved U-box containing proteins in eukaryotes. They are subunits of the MOS4-associated complex (MAC) that plays essential roles in plant immunity and development in Arabidopsis. However, their functional mechanisms remain elusive. Here we show that Arabidopsis thaliana MAC3A and MAC3B act redundantly in microRNA (miRNA) biogenesis. Lack of both MAC3A and MAC3B in the mac3b mac3b double mutant reduces the accumulation of miRNAs, causing elevated transcript levels of miRNA targets. mac3a mac3b also decreases the levels of primary miRNA transcripts (pri-miRNAs). However, MAC3A and MAC3B do not affect the promoter activity of genes encoding miRNAs ( …

Provitamin A Biofortification Of Cassava Enhances Shelf Life But Reduces Dry Matter Content Of Storage Roots Due To Altered Carbon Partitioning Into Starch, Getu Beyene, Felix R. Solomon, Raj D. Chauhan, Eliana Gaitán-Solis, Narayanan Narayanan, Jackson Gehan, Dimuth Siritunga, Robin L. Stevens, John Jifon, Joyce Van Eck, Edward Linsler, Malia Gehan, Muhammad Ilyas, Martin Fregene, Richard T. Sayre, Paul Anderson, Nigel Taylor, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty Publications

Storage roots of cassava (Manihot esculenta Crantz), a major subsistence crop of sub-Saharan Africa, are calorie rich but deficient in essential micronutrients, including provitamin A β-carotene. In this study, β-carotene concentrations in cassava storage roots were enhanced by coexpression of transgenes for deoxy-d-xylulose-5-phosphate synthase (DXS) and bacterial phytoene synthase (crtB), mediated by the patatin-type 1 promoter. Storage roots harvested from field-grown plants accumulated carotenoids to ≤50 lg/g DW, 15- to 20-fold increases relative to roots from nontransgenic plants. Approximately 85%–90% of these carotenoids accumulated as all-trans-β-carotene, the most nutritionally efficacious carotenoid. β-Carotene-accumulating storage roots displayed delayed onset of postharvest …

Differentially Regulated Orthologs In Sorghum And The Subgenomes Of Maize, Yang Zhang, Daniel W. Ngu, Daniel Santana De Carvalho, Zhikai Liang, Yumou Qiu, Rebecca Roston, James C. Schnable

Center for Plant Science Innovation: Faculty Publications

Identifying interspecies changes in gene regulation, one of the two primary sources of phenotypic variation, is challenging on a genome-wide scale. The use of paired time-course data on cold-responsive gene expression in maize (Zea mays) and sorghum (Sorghum bicolor) allowed us to identify differentially regulated orthologs. While the majority of cold-responsive transcriptional regulation of conserved gene pairs is species specific, the initial transcriptional responses to cold appear to be more conserved than later responses. In maize, the promoters of genes with conserved transcriptional responses to cold tend to contain more micrococcal nuclease hypersensitive sites in their …

Dissecting The Genetic Basis Of Salt Tolerance In Rice (Oryza Sativa), Malachy Thomas Campbell

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Excessive salt is a major factor limiting crop productivity. Rice is an important food crop worldwide, and provides a major source of calories for billions of people in tropical and subtropical developing countries. In many regions throughout Southeast Asia, rice is grown in low-lying coastal regions, which are prone to ingress by seawater. Rice is highly sensitive to salt stress, with mild salinity resulting in large reductions in yield. Improving salt tolerance in rice is essential for ensuring food security for many individuals throughput the developing world.

In this work, the overall goals were to characterize a diverse collection of …

A Specialized Diacylglycerol Acyltransferase Contributes To The Extreme Medium-Chain Fatty Acid Content Of Cuphea Seed Oil, Umidjon Iskandarov, Jillian E. Silva, Hae Jin Kim, Mariette Andersson, Rebecca E. Cahoon, Keithanne Mockaitis, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty Publications

Seed oils of many Cuphea sp. contain .90% of medium-chain fatty acids, such as decanoic acid (10:0). These seed oils, which are among the most compositionally variant in the plant kingdom, arise from specialized fatty acid biosynthetic enzymes and specialized acyltransferases. These include lysophosphatidic acid acyltransferases (LPAT) and diacylglycerol acyltransferases (DGAT) that are required for successive acylation of medium-chain fatty acids in the sn-2 and sn-3 positions of seed triacylglycerols (TAGs). Here we report the identification of a cDNA for a DGAT1-type enzyme, designated CpuDGAT1, from the transcriptome of C. avigera var pulcherrima developing seeds. Microsomes of camelina (Camelina …

High And Low Yielding Soybean Lines From An Irrigated Selection Environment: Performance Evaluation In Irrigated And Droughted Environments, Jorge E. Perez Arocho

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Drought is the most significant abiotic stress affecting agricultural production. Improving seed yield under water stress is an important breeding objective. Soybean cultivars that tolerate water stress could help improve and stabilize production in water-stressed environments. “Drought” needs to be defined, because water stress can vary in intensity, timing, and duration. Other factors including ambient temperature, soil texture, depth, and fertility will influence the impact of limited water on crop productivity. This research addresses the impact of water stress on soybeans adapted to the north-central US, where the majority of soils are relatively deep, fertile silt loams or silty clay …

The Lx Report Of The Bean Improvement Cooperative No. 60, March 2017.

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

CONTENTS

LX Annual Report of the Bean Improvement Cooperative xi

BIC Coordinating Committee Membership - 1957 to 2017 . xii

BIC Meritorious Service and Distinguished Achievement Award Recipients - 1957 to 2015 xiii

BIC Awards Nomination Request for 2017 xvi

BIC/NAPIA Meeting in 2017 . xix

In Memory of Guillermo E. Galvez-Enriquez xx

RESEARCH PAPERS FOR 2017

OPTIMIZING SPORULATION OF Pseudocercospora griseola IN VITRO • Paula F. de Pádua1, Rafael Pereira1, Luanna B. W. Gomes1 and Elaine A. de Souza1* 1

FINE MAPPING THE BROAD SPECTRUM ANTHRACNOSE RESISTANCE GENE IN AMENDOIM CAVALO 3 • Gilio, T.A.S.1, Oscar P. Hurtado-Gonzales2, Giseli …

Towards The Development Of A Sustainable Soya Bean-Based Feedstock For Aquaculture, Hyunwoo Park, Steven Weier, Fareha Razvi, Pamela A. Peña, Neil A. Sims, Jennica Lowell, Cory Hungate, Karma Kissinger, Gavin Key, Paul Fraser, Jonathan Napier, Edgar B. Cahoon, Thomas Clemente

Center for Plant Science Innovation: Faculty Publications

Soya bean (Glycine max (L.) Merr.) is sought after for both its oil and protein components. Genetic approaches to add value to either component are ongoing efforts in soya bean breeding and molecular biology programmes. The former is the primary vegetable oil consumed in the world. Hence, its primary usage is in direct human consumption. As a means to increase its utility in feed applications, thereby expanding the market of soya bean coproducts, we investigated the simultaneous displacement of marine ingredients in aquafeeds with soya bean-based protein and a high Omega-3 fatty acid soya bean oil, enriched with alpha-linolenic …

Cognition-Mediated Evolution Of Low-Quality Floral Nectars, Vladislav Nachev, Kai Petra Stich, Clemens Winter, Alan B. Bond, Alan Kamil, York Winter

Alan Bond Publications

Plants pollinated by hummingbirds or bats produce dilute nectars even though these animals prefer more concentrated sugar solutions. This mismatch is an unsolved evolutionary paradox. Here we show that lower quality, or more dilute, nectars evolve when the strength of preferring larger quantities or higher qualities of nectar diminishes as magnitudes of the physical stimuli increase. In a virtual evolution experiment conducted in the tropical rainforest, bats visited computer-automated flowers with simulated genomes that evolved relatively dilute nectars. Simulations replicated this evolution only when value functions, which relate the physical stimuli to subjective sensations, were nonlinear. Selection also depended on …

Enhancing Soybean Photosynthetic Co2 Assimilation Using A Cyanobacterial Membrane Protein, Ictb, William T. Hay, Saadia Bihmidine, Nedim Mutlu, Khang Le Hoang, Tala Awada, Donald P. Weeks, Thomas Clemente, Stephen P. Long

Center for Plant Science Innovation: Faculty Publications

Soybean C₃ photosynthesis can suffer a severe loss in efficiency due to photorespiration and the lack of a carbon concentrating mechanism (CCM) such as those present in other plant species or cyanobac-teria. Transgenic soybean (Glycine max cv. Thorne) plants constitutively expressing cyanobacterial ictB (inorganic carbon transporter B) gene were generated using Agrobacterium-mediated transformation. Although more recent data suggest that ictB does not actively transport HCO3-/CO2, there is nevertheless mounting evidence that transformation with this gene can increase higher plant photosynthesis. The hypothesis that expression of the ictB gene would improve photosynthesis, biomass production and seed yield in soybean …

A Multidomain Enzyme, With Glycerol-3-Phosphate Dehydrogenase And Phosphatase Activities, Is Involved In A Chloroplastic Pathway For Glycerol Synthesis In Chlamydomonas Reinhardtii, Daniela Morales-Sánchez, Yeongho Kim, Ee Leng Terng, Laura Peterson, Heriberto D. Cerutti

Center for Plant Science Innovation: Faculty Publications

Understanding the unique features of algal metabolism may be necessary to realize the full potential of algae as feedstock for the production of biofuels and biomaterials. Under nitrogen deprivation, the green alga C. reinhardtii showed substantial triacylglycerol (TAG) accumulation and up-regulation of a gene, GPD2, encoding a multidomain enzyme with a putative phosphoserine phosphatase (PSP) motif fused to glycerol-3-phosphate dehydrogenase (GPD) domains. Canonical GPD enzymes catalyze the synthesis of glycerol-3-phosphate (G3P) by reduction of dihydroxyacetone phosphate (DHAP). G3P forms the backbone of TAGs and membrane glycerolipids and it can be dephosphorylated to yield glycerol, an osmotic stabilizer and compatible …

Expression Of Cyanobacterial Fbp/Sbpase In Soybean Prevents Yield Depression Under Future Climate Conditions, Iris H. Köhler, Ursula M. Ruiz-Vera, Andy Vanloocke, Michell L. Thomey, Thomas Clemente, Stephen P. Long, Donald R. Ort, Carl J. Bernacchi

Center for Plant Science Innovation: Faculty Publications

Predictions suggest that current crop production needs to double by 2050 to meet global food and energy demands. Based on theory and experimental studies, overexpression of the photosynthetic enzyme sedoheptulose-1,7-bisphosphatase (SBPase) is expected to enhance C₃ crop photosynthesis and yields. Here we test how expression of the cyanobacterial, bifunctional fructose-1,6/sedoheptulose-1,7-bisphosphatase (FBP/SBPase) affects carbon assimilation and seed yield (SY) in a major crop (soybean, Glycine max). For three growing seasons, wild-type (WT) and FBP/SBPase-expressing (FS) plants were grown in the field under ambient (400 μmol mol⁻¹) and elevated (600 μmol mol⁻¹) CO₂ concentrations [CO …

Overexpression Of Sbmyb60 In Sorghum Bicolor Impacts Both Primary And Secondary Metabolism, Erin D. Scully, Tammy Gries, Nathan A. Palmer, Gautam Sarath, Deanna L. Funnell-Harris, Lisa Baird, Paul Twigg, Javier Seravalli, Thomas E. Clemente, Scott E. Sattler

Center for Plant Science Innovation: Faculty Publications

• Few transcription factors have been identified in C₄ grasses that either positively or negatively regulate monolignol biosynthesis.
• Previously, the overexpression of SbMyb60 in sorghum (Sorghum bicolor) has been shown to induce monolignol biosynthesis, which leads to elevated lignin deposition and altered cell wall composition. To determine how SbMyb60 overexpression impacts other metabolic pathways, RNA-Seq and metabolite profiling were performed on stalks and leaves.
• 35S::SbMyb60 was associated with the transcriptional activation of genes involved in aromatic amino acid, S-adenosyl methionine (SAM) and folate biosynthetic pathways. The high coexpression values between SbMyb60 and genes assigned to these pathways indicate …

Complete Mitochondrial Genomes From The Ferns Ophioglossum Californicum And Psilotum Nudum Are Highly Repetitive With The Largest Organellar Introns, Wenhu Guo, Andan Zhu, Weishu Fan, Jeffrey P. Mower

Center for Plant Science Innovation: Faculty Publications

• Currently, complete mitochondrial genomes (mitogenomes) are available from all major land plant lineages except ferns. Sequencing of fern mitogenomes could shed light on the major evolutionary transitions that established mitogenomic diversity among extant lineages.

• In this study, we generated complete mitogenomes from the adder’s tongue fern (Ophioglossum californicum) and the whisk fern (Psilotum nudum).

• The Psilotum mitogenome (628 kb) contains a rich complement of genes and introns, some of which are the largest of any green plant organellar genome. In the Ophioglossum mitogenome (372 kb), gene and intron content is slightly reduced, including the loss of …

  ---

  Go to article