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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 ...


Linking Autophagy To Abiotic And Biotic Stress Responses, Santiago Signorelli, Lukasz Pawel Tarkowski, Wim Van Den Ende, Diane C. Bassham Feb 2019

Linking Autophagy To Abiotic And Biotic Stress Responses, Santiago Signorelli, Lukasz Pawel Tarkowski, Wim Van Den Ende, Diane C. Bassham

Genetics, Development and Cell Biology Publications

Autophagy is a process in which cellular components are delivered to lytic vacuoles to be recycled and has been demonstrated to promote abiotic/biotic stress tolerance. Here, we review how the responses triggered by stress conditions can affect autophagy and its signaling pathways. Besides the role of SNF-related kinase 1 (SnRK1) and TOR kinases in the regulation of autophagy, abscisic acid (ABA) and its signaling kinase SnRK2 have emerged as key players in the induction of autophagy under stress conditions. Furthermore, an interplay between reactive oxygen species (ROS) and autophagy is observed, ROS being able to induce autophagy and autophagy ...


Genetic And Environmental Variation Impact The Cuticular Hydrocarbon Metabolome On The Stigmatic Surfaces Of Maize, Tesia Dennison, Wenmin Qin, Derek M. Loneman, Samson G. F. Condon, Nick Lauter, Basil J. Nikolau, Marna D. Yandeau-Nelson Jan 2019

Genetic And Environmental Variation Impact The Cuticular Hydrocarbon Metabolome On The Stigmatic Surfaces Of Maize, Tesia Dennison, Wenmin Qin, Derek M. Loneman, Samson G. F. Condon, Nick Lauter, Basil J. Nikolau, Marna D. Yandeau-Nelson

Genetics, Development and Cell Biology Publications

Background: Simple non-isoprenoid hydrocarbons accumulate in discrete regions of the biosphere, including within bacteria and algae as a carbon and/or energy store, and the cuticles of plants and insects, where they may protect against environmental stresses. The extracellular cuticular surfaces of the stigmatic silks of maize are rich in linear hydrocarbons and therefore provide a convenient system to study the biological origins and functions of these unique metabolites.

Results: To test the hypotheses that genetics and environment influence the accumulation of surface hydrocarbons on silks and to examine the breadth of metabolome compositions across diverse germplasm, cuticular hydrocarbons were ...


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 ...


From Arabidopsis To Crops: The Arabidopsis Qqs Orphan Gene Modulates Nitrogen Allocation Across Species, Seth O'Conner, Andrea Neudorf, Wenguang Zheng, Mingsheng Qi, Xuefeng Zhao, Chuanlong Du, Dan Nettleton, Ling Li Jan 2018

From Arabidopsis To Crops: The Arabidopsis Qqs Orphan Gene Modulates Nitrogen Allocation Across Species, Seth O'Conner, Andrea Neudorf, Wenguang Zheng, Mingsheng Qi, Xuefeng Zhao, Chuanlong Du, Dan Nettleton, Ling Li

Genetics, Development and Cell Biology Publications

To improve the nitrogen use efficiency (NUE) of crops to increase yields, one approach is to develop crops with improved NUE. Qua Quine Starch (QQS), a species-specific orphan gene present only in Arabidopsis thaliana, has a novel, unexpected functionality. Approximately 0.5- 8% of genes in a given species are uniquely present in that species, having no homologs in other species. They represent a significant fraction of eukaryotic and prokaryotic genomes, and are thought to be a determinant of the character of a species. However, little is known about the functional significance of these so-called species-specific or orphan genes. QQS ...


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 ...


Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges, Mark A. Chamberlin, Marc C. Albertsen, Harry T. Horner Oct 2017

Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges, Mark A. Chamberlin, Marc C. Albertsen, Harry T. Horner

Genetics, Development and Cell Biology Publications

Premise of research. A male-sterile, female-sterile mutant was discovered in a w4-m mutable line of Glycine max L. The mechanism of its sterility was not well understood. Therefore, different cytological and microscopic techniques were undertaken to better understand the process of mutant phenotype development. Molecular research indicated that mer3 was responsible for the sterility.

Methodology. Macro images were collected of whole plants, flowers, anthers, pods, and ovules. Chromosome spreads from anthers at various meiotic stages were examined. Confocal scanning laser microscopy using optical sectioning was utilized on whole anthers and ovules at various developmental stages. Whole mature anthers and ...


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 ...


A Robust And Efficient Method For The Extraction Of Plant Extracellular Surface Lipids As Applied To The Analysis Of Silks And Seedling Leaves Of Maize, Derek M. Loneman, Layton Peddicord, Amani Al-Rashid, Basil J. Nikolau, Nick Lauter, Marna D. Yandeau-Nelson Jul 2017

A Robust And Efficient Method For The Extraction Of Plant Extracellular Surface Lipids As Applied To The Analysis Of Silks And Seedling Leaves Of Maize, Derek M. Loneman, Layton Peddicord, Amani Al-Rashid, Basil J. Nikolau, Nick Lauter, Marna D. Yandeau-Nelson

Genetics, Development and Cell Biology Publications

Aerial plant organs possess a diverse array of extracellular surface lipids, including both non-polar and amphipathic constituents that collectively provide a primary line of defense against environmental stressors. Extracellular surface lipids on the stigmatic silks of maize are composed primarily of saturated and unsaturated linear hydrocarbons, as well as fatty acids, and aldehydes. To efficiently extract lipids of differing polarities from maize silks, five solvent systems (hexanes; hexanes:diethyl ether (95:5); hexanes:diethyl ether (90:10); chloroform:hexanes (1:1) and chloroform) were tested by immersing fresh silks in solvent for different extraction times. Surface lipid recovery and the ...


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 ...


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 ...


An Agrobacterium-Delivered Crispr/Cas9 System For High-Frequency Targeted Mutagenesis In Maize, Si Nian Char, Anjanasree K. Neelakandan, Hartinio Nahampun, Bronwyn Frame, Marcy Main, Martin H. Spalding, Philip W. Becraft, Blake C. Meyers, Virginia Walbot, Kan Wang, Bing Yang Feb 2017

An Agrobacterium-Delivered Crispr/Cas9 System For High-Frequency Targeted Mutagenesis In Maize, Si Nian Char, Anjanasree K. Neelakandan, Hartinio Nahampun, Bronwyn Frame, Marcy Main, Martin H. Spalding, Philip W. Becraft, Blake C. Meyers, Virginia Walbot, Kan Wang, Bing Yang

Genetics, Development and Cell Biology Publications

CRISPR/Cas9 is a powerful genome editing tool in many organisms, including a number of monocots and dicots. Although the design and application of CRISPR/Cas9 is simpler compared to other nuclease-based genome editing tools, optimization requires the consideration of the DNA delivery and tissue regeneration methods for a particular species to achieve accuracy and efficiency. Here, we describe a public sector system, ISU Maize CRISPR, utilizing Agrobacterium-delivered CRISPR/Cas9 for high-frequency targeted mutagenesis in maize. This system consists of an Escherichia coli cloning vector and an Agrobacterium binary vector. It can be used to clone up to four ...


Peruvian Window-Leaved Peperomia Taxa Display Unique Crystal Macropatterns In High-Altitude Environments, Harry T. Horner, Stefan Wanke, Birgit Oelschlägel, Marie-Stéphanie Samain Feb 2017

Peruvian Window-Leaved Peperomia Taxa Display Unique Crystal Macropatterns In High-Altitude Environments, Harry T. Horner, Stefan Wanke, Birgit Oelschlägel, Marie-Stéphanie Samain

Genetics, Development and Cell Biology Publications

Premise of research. Window-leaved Peperomia taxa (WPs) occur in the Peruvian Andes from near sea level to high altitudes and display curled leaves that are generally exposed to high irradiance and periodic drought, far different from the typically uncurled humid-forest, often-shaded Peperomia taxa. Even though representatives of the latter taxa, as well as other members of the Piperales, have been observed for the presence (type) and location (macropattern) of leaf crystals in previous studies, this special group of WP taxa has missed scrutiny. It was important to determine whether the WP taxa contained the same types of crystals in the ...


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 ...


Nkd Transcription Factors Are Central Regulators Of Maize Endosperm Development, Bryan C. Gontarek, Anjanasree K. Neelakandan, Hao Wu, Philip W. Becraft Dec 2016

Nkd Transcription Factors Are Central Regulators Of Maize Endosperm Development, Bryan C. Gontarek, Anjanasree K. Neelakandan, Hao Wu, Philip W. Becraft

Genetics, Development and Cell Biology Publications

NAKED ENDOSPERM1 (NKD1) and NKD2 are duplicate INDETERMINATE DOMAIN (IDD) transcription factors important for maize (Zea mays) endosperm development. RNA-seq analysis of the nkd1 nkd2 mutant endosperm revealed that NKD1 and NKD2 influence 6.4% of the transcriptome in developing aleurone and 6.7% in starchy endosperm. Processes regulated by NKD1 and NKD2 include gene expression, epigenetic functions, cell growth and division, hormone pathways, and resource reserve deposition. The NKD1 and NKD2 proteins bind a consensus DNA sequence of TTGTCGT with slightly different properties. This motif was enriched in the promoters of gene transcripts differentially expressed (DE) in mutant endosperm ...


Stochastic Optical Reconstruction Microscopy Imaging Of Microtubule Arrays In Intact Arabidopsis Thaliana Seedling, Bin Dong, Xiaochen Yang, Shaobin Zhu, Diane C. Bassham, Ning Fang Jan 2015

Stochastic Optical Reconstruction Microscopy Imaging Of Microtubule Arrays In Intact Arabidopsis Thaliana Seedling, Bin Dong, Xiaochen Yang, Shaobin Zhu, Diane C. Bassham, Ning Fang

Genetics, Development and Cell Biology Publications

Super-resolution fluorescence microscopy has generated tremendous success in revealing detailed subcellular structures in animal cells. However, its application to plant cell biology remains extremely limited due to numerous technical challenges, including the generally high fluorescence background of plant cells and the presence of the cell wall. In the current study, stochastic optical reconstruction microscopy (STORM) imaging of intact Arabidopsis thaliana seedling roots with a spatial resolution of 20–40 nm was demonstrated. Using the super-resolution images, the spatial organization of cortical microtubules in different parts of a whole Arabidopsis root tip was analyzed quantitatively, and the results show the dramatic ...


New And Unusual Forms Of Calcium Oxalate Raphide Crystals In The Plant Kingdom, Vijayasankar Raman, Harry T. Horner, Ikhlas A. Khan Nov 2014

New And Unusual Forms Of Calcium Oxalate Raphide Crystals In The Plant Kingdom, Vijayasankar Raman, Harry T. Horner, Ikhlas A. Khan

Genetics, Development and Cell Biology Publications

Calcium oxalate crystals in higher plants occur in five major forms namely raphides, styloids, prisms, druses and crystal sand. The form, shape and occurrence of calcium oxalate crystals in plants are species- and tissue-specific, hence the presence or absence of a particular type of crystal can be used as a taxonomic character. So far, four different types of needle-like raphide crystals have been reported in plants. The present work describes two new and unusual forms of raphide crystals from the tubers of Dioscorea polystachya—six-sided needles with pointed ends (Type V) and four-sided needles with beveled ends (Type VI). Both ...


Molecular Mapping Of D1, D2 And Ms5 Revealed Linkage Between The Cotyledon Color Locus D2 And The Male-Sterile Locus Ms5 In Soybean, Alina Ott, Yang Yang, Madan Bhattacharyya, Harry T. Horner, Reid G. Palmer, Devinder Sandhu Jan 2013

Molecular Mapping Of D1, D2 And Ms5 Revealed Linkage Between The Cotyledon Color Locus D2 And The Male-Sterile Locus Ms5 In Soybean, Alina Ott, Yang Yang, Madan Bhattacharyya, Harry T. Horner, Reid G. Palmer, Devinder Sandhu

Genetics, Development and Cell Biology Publications

In soybean, genic male sterility can be utilized as a tool to develop hybrid seed. Several male-sterile, female-fertile mutants have been identified in soybean. The male-sterile, female-fertile ms5 mutant was selected after fast neutron irradiation. Male-sterility due to ms5 was associated with the “stay-green” cotyledon color mutation. The cotyledon color trait in soybean is controlled by two loci, D1 and D2. Association between cotyledon color and male-sterility can be instrumental in early phenotypic selection of sterility for hybrid seed production. The use of such selection methods saves time, money, and space, as fewer seeds need to be planted and screened ...


High-Throughput Linkage Analysis Of Mutator Insertion Sites In Maize, Gibum Yi, Diane Luth, Timothy D. Goodman, Carolyn J. Lawrence, Philip W. Becraft Jun 2009

High-Throughput Linkage Analysis Of Mutator Insertion Sites In Maize, Gibum Yi, Diane Luth, Timothy D. Goodman, Carolyn J. Lawrence, Philip W. Becraft

Genetics, Development and Cell Biology Publications

Insertional mutagenesis is a cornerstone of functional genomics. High-copy transposable element systems such as Mutator (Mu) in maize (Zea mays) afford the advantage of high forward mutation rates but pose a challenge for identifying the particular element responsible for a given mutation. Several large mutant collections have been generated in Mu-active genetic stocks, but current methods limit the ability to rapidly identify the causal Mu insertions. Here we present a method to rapidly assay Mu insertions that are genetically linked to a mutation of interest. The method combines elements of MuTAIL (thermal asymmetrically interlaced) and amplification of insertion mutagenized ...


Multicellular Secretory Trichome Development On Soybean And Related Glycine Gynoecia, R. A. Healy, R. G. Palmer, Harry T. Horner May 2009

Multicellular Secretory Trichome Development On Soybean And Related Glycine Gynoecia, R. A. Healy, R. G. Palmer, Harry T. Horner

Genetics, Development and Cell Biology Publications

Multicellular glandular trichomes form on gynoecia of wild annual Glycine species, annual soybean cultivars, and wild perennial Glycine species. These trichomes occur from the ovary base to the style base and, in perennial species, along the style as well.Trichomes form at least 2 d before anthesis, and new trichomes develop throughout flowering and also on young seed pods. Trichome structure is similar in all taxa examined, usually five to seven linearly arranged cells. Stalk cells with callose walls become highly vacuolate, and their cytoplasms have reduced numbers of Golgi bodies and endoplasmic reticulum. During secretion, two to four distal ...


Evolution And Systematic Value Of Leaf Crystal Macropatterns In The Genus Peperomia (Piperaceae), Harry T. Horner, Stefan Wanke, Marie-Stephanie Samain Jan 2009

Evolution And Systematic Value Of Leaf Crystal Macropatterns In The Genus Peperomia (Piperaceae), Harry T. Horner, Stefan Wanke, Marie-Stephanie Samain

Genetics, Development and Cell Biology Publications

Leaves of Peperomia species vary in texture, shape, succulence, lamina size, thickness, coloration, and venation. Each leaf contains only calcium oxalate druses in palisade cells, druses in palisade and raphides in spongy parenchyma, or druses in palisade and prisms in spongy parenchyma. Collectively, these variations create distinct crystal macropatterns. Leaves from 45 species were studied to identify their macropatterns and to compare the macropatterns with molecular data. Microscopic data showed two major crystal macropatterns and five variations of them. All but one species displayed either a single druse in most palisade cells forming one or more uniform crystal layers (81 ...


The Male Sterility Locus Ms3 Is Present In A Fertility Controlling Gene Cluster In Soybean, Innan Cervantes-Martinez, Devinder Sandhu, Min Xu, Evelyn Ortiz-Perez, Kiyoaki K. Kato, Harry T. Horner, Reid G. Palmer Jan 2009

The Male Sterility Locus Ms3 Is Present In A Fertility Controlling Gene Cluster In Soybean, Innan Cervantes-Martinez, Devinder Sandhu, Min Xu, Evelyn Ortiz-Perez, Kiyoaki K. Kato, Harry T. Horner, Reid G. Palmer

Genetics, Development and Cell Biology Publications

Soybean [Glycine max (L.) Merr.] is self-pollinated. To produce large quantities of hybrid seed, insect-mediated cross-pollination is necessary. An efficient nuclear male-sterile system for hybrid seed production would benefit from molecular and/or phenotypic markers linked to male fertility/sterility loci to facilitate early identification of phenotypes. Nuclear male-sterile, female-fertile ms3 mutant is a single recessive gene and displays high outcrossed seed set with pollinators. Our objective was to map the ms3 locus. A segregating population of 150 F2 plants from Minsoy (PI 27890) × T284H, Ms3ms3 (A00-68), was screened with 231 simple sequence repeat markers. The ms3 locus mapped ...


Structural Adaptations In Overwintering Leaves Of Thermonastic And Nonthermonastic Rhododendron Species, Xiang Wang, Rajeev Arora, Harry T. Horner, Stephen L. Krebs Nov 2008

Structural Adaptations In Overwintering Leaves Of Thermonastic And Nonthermonastic Rhododendron Species, Xiang Wang, Rajeev Arora, Harry T. Horner, Stephen L. Krebs

Genetics, Development and Cell Biology Publications

Evergreen rhododendrons (Rhododendron L.) are important woody landscape plants in many temperate zones. During winters, leaves of these plants frequently are exposed to a combination of cold temperatures, high radiation, and reduced photosynthetic activity, conditions that render them vulnerable to photooxidative damage. In addition, these plants are shallow-rooted and thus susceptible to leaf desiccation when soils are frozen. In this study, the potential adaptive significance of leaf morphology and anatomy in two contrasting Rhododendron species was investigated. R. catawbiense Michx. (native to eastern United States) exhibits thermonasty (leaf drooping and curling at subfreezing temperatures) and is more winter-hardy [leaf freezing ...


Insect-Mediated Cross-Pollination In Soybean [Glycine Max (L.) Merrill]: Ii. Phenotypic Recurrent Selection, Evelyn Ortiz-Perez, Hunt Wiley, Harry T. Horner, William H. Davis, Reid G. Palmer Jul 2008

Insect-Mediated Cross-Pollination In Soybean [Glycine Max (L.) Merrill]: Ii. Phenotypic Recurrent Selection, Evelyn Ortiz-Perez, Hunt Wiley, Harry T. Horner, William H. Davis, Reid G. Palmer

Genetics, Development and Cell Biology Publications

Recurrent selection is a method for population improvement which has been used in soybean [Glycine max (L.) Merrill] to modify traits such as grain yield, seed-protein content, seed-oil content, tolerance to iron-deficiency chlorosis, and seed size. Nuclear male-sterility with insect-mediated cross-pollination has been successfully used in recurrent selection schemes in soybean. However, little attention has been given to selection to increase the agronomic performance of male-sterile plants per se. The objective of this study was to evaluate the response of male-sterile lines segregating for male-sterile alleles ms2, ms3, ms6, ms8, and ms9 to phenotypic recurrent selection for increased seed-set after ...


Regulon Organization Of Arabidopsis, Wieslawa I. Mentzen, Eve S. Wurtele Jan 2008

Regulon Organization Of Arabidopsis, Wieslawa I. Mentzen, Eve S. Wurtele

Genetics, Development and Cell Biology Publications

Background: Despite the mounting research on Arabidopsis transcriptome and the powerful tools to explore biology of this model plant, the organization of expression of Arabidopsis genome is only partially understood. Here, we create a coexpression network from a 22,746 Affymetrix probes dataset derived from 963 microarray chips that query the transcriptome in response to a wide variety of environmentally, genetically, and developmentally induced perturbations.

Results: Markov chain graph clustering of the coexpression network delineates 998 regulons ranging from one to 1623 genes in size. To assess the significance of the clustering results, the statistical over-representation of GO terms is ...


Insect-Mediated Cross-Pollination In Soybean [Glycine Max (L.) Merrill] : I. Agronomic Performance, E. Ortiz-Perez, S. R. Cianzio, H. Wiley, Harry T. Horner, W. H. Davis, R. G. Palmer Jan 2007

Insect-Mediated Cross-Pollination In Soybean [Glycine Max (L.) Merrill] : I. Agronomic Performance, E. Ortiz-Perez, S. R. Cianzio, H. Wiley, Harry T. Horner, W. H. Davis, R. G. Palmer

Genetics, Development and Cell Biology Publications

In soybean, manual cross-pollination to produce large quantities of F1 hybrid seed for yield trials is difficult and time-consuming. Conversely, insect-mediated cross-pollination has been shown to produce large quantities of hybrid seed in soybean and could facilitate the identification of heterotic patterns. The objective of our study was: (1) evaluate F1hybrid soybean plants from single crosses for yield and agronomic traits over several environments and (2) compare hybrid performance of the single crosses to lines developed from three-way crosses and backcrosses. In 2003, F1 seed of single-crosses and their parent lines were evaluated in replicated experiments ...


Molecular Mapping Of Male-Sterility Loci Ms2 And Ms9 In Soybean, I. Cervantes-Martinez, M. Xu, L. Zhang, Z. Huang, K. K. Kato, Harry T. Horner, R. G. Palmer Jan 2007

Molecular Mapping Of Male-Sterility Loci Ms2 And Ms9 In Soybean, I. Cervantes-Martinez, M. Xu, L. Zhang, Z. Huang, K. K. Kato, Harry T. Horner, R. G. Palmer

Genetics, Development and Cell Biology Publications

Markers linked to male-sterile, female-fertile loci on the soybean [Glycine max (L.) Merr.] molecular map would facilitate early identification of male-sterile plants. The objectives were to verify the chromosome location of the ms2 (A00–63) mutation, to determine the allelism and the chromosome location of the suspected ms2 [ms? (A00–39)] mutation, and to determine the chromosome location of the ms9 (T359) mutation. Simple sequence repeat (SSR) markers were used to molecularly map the male-sterile, female-fertile loci reported in this study. Segregating F2 populations were developed from crosses of ms?ms? (A00–39) × ‘Minsoy’ (PI 278901), ms2ms2 (A00–63 ...