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Full-Text Articles in Life Sciences

A Gradient Of Pollination Specialization In Three Species Of Bolivian Centropogon, Laura Lagomarsino, Nathan Muchhala May 2019

A Gradient Of Pollination Specialization In Three Species Of Bolivian Centropogon, Laura Lagomarsino, Nathan Muchhala

Biology Department Faculty Works

PremiseClosely related plant species with overlapping ranges often experience competition for pollination services. Such competition can select for divergence in floral traits that attract pollinators or determine pollen placement. While most species in Centropogon(Campanulaceae: Lobelioideae) have flowers that suggest adaptation to bat or hummingbird pollination, actual pollinators are rarely documented, and a few species have a mix of traits from both pollination syndromes. We studied the pollination biology of a “mixed‐syndrome” species and its co‐occurring congeners to examine the relationship between floral traits and visitation patterns for Centropogon.Methods Fieldwork at two sites in Bolivian cloud forests involved filming floral visitors, …


Evolution Of Floral Zygomorphy In Androecium And Corolla In Solanaceae, Jingbo Zhang, Peter Stevens, Wenheng Zhang Jan 2017

Evolution Of Floral Zygomorphy In Androecium And Corolla In Solanaceae, Jingbo Zhang, Peter Stevens, Wenheng Zhang

Biology Department Faculty Works

In Solanaceae, a group dominated by actinomorphic‐flowered species, floral zygomorphy is frequently observed among the early‐branching clades. Morphological studies indicated that a zygomorphic androecium is much more common than a zygomorphic corolla in the family. Ontogenic studies suggested the evolution of floral zygomorphy in these two whorls is independent. Here, we have examined the evolution of floral symmetry in the androecium and corolla in Solanaceae. The character states of floral symmetry were assembled for androecium and corolla separately, and ancestral state reconstructions were carried out at both the genus and species levels for Solanaceae and its outgroups. Correlation tests were …


Phospholipase Dζ Enhances Diacylglycerol Flux Into Triacylglycerol, Wenyu Yang, Geliang Wang, Jia Li, Philip Bates, Xuemin Wang, Douglas Allen Jan 2017

Phospholipase Dζ Enhances Diacylglycerol Flux Into Triacylglycerol, Wenyu Yang, Geliang Wang, Jia Li, Philip Bates, Xuemin Wang, Douglas Allen

Biology Department Faculty Works

Plant seeds are the primary source of triacylglycerols (TAG) for food, feed, fuel, and industrial applications. As TAG is produced from diacylglycerol (DAG), successful engineering strategies to enhance TAG levels have focused on the conversion of DAG to TAG. However, the production of TAG can be limited by flux through the enzymatic reactions that supply DAG. In this study, two Arabidopsis phospholipase Dζ genes (AtPLDζ1 and AtPLDζ2) were coexpressed in Camelina sativa to test whether the conversion of phosphatidylcholine to DAG impacts TAG levels in seeds. The resulting transgenic plants produced 2% to 3% more TAG as a component of …


Seed Dispersal For The Unusual Inflated Berries Of Burmeistera (Campanulaceae), Diana Gamba, N. Maguiña, Camilo Calderón-Acevedo, Karina Torres, Nathan Muchhala Jan 2017

Seed Dispersal For The Unusual Inflated Berries Of Burmeistera (Campanulaceae), Diana Gamba, N. Maguiña, Camilo Calderón-Acevedo, Karina Torres, Nathan Muchhala

Biology Department Faculty Works

Examining dispersal is critical for understanding the diversity of Andean-centered plant lineages, like Burmeistera (Campanulaceae). One-third of its species present an unusual inflated berry. Unlike the bright colors of non-inflated fruits in the genus, these fruits are typically dull-green; however, the fact that the seeds are loosely held in the placenta and easily removed when touched seems to suggest adaptation to animal dispersal. We studied two inflated-baccate species, Burmeistera glabrata and B. borjensis, with the aim of testing the non-exclusive hypotheses that their seeds are dispersed by (1) small mammals, (2) slugs, or (3) adult flies that develop inside the …


Non-Specific Phospholipase C1 Affects Silicon Distribution And Mechanical Strength In Stem Nodes Of Rice, Huasheng Cao, Lin Zhuo, Yuan Su, Linxiao Sun, Xuemin Wang May 2016

Non-Specific Phospholipase C1 Affects Silicon Distribution And Mechanical Strength In Stem Nodes Of Rice, Huasheng Cao, Lin Zhuo, Yuan Su, Linxiao Sun, Xuemin Wang

Biology Department Faculty Works

Silicon, the second abundant element in the crust, is beneficial for plant growth, mechanical strength, and stress responses. Here we show that manipulation of the non‐specific phospholipase C1, NPC1, alters silicon content in nodes and husks of rice (Oryza sativa). Silicon content in NPC1‐overexpressing (OE) plants was decreased in nodes but increased in husks compared to wild‐type, whereas RNAi suppression of NPC1 resulted in the opposite changes to those of NPC1‐OE plants. NPC1 from rice hydrolyzed phospholipids and galactolipids to generate diacylglycerol that can be phosphorylated to phosphatidic acid. Phosphatidic acid interacts with Lsi6, a silicon transporter that is expressed …


Membrane Glycerolipidome Of Soybean Root Hairs And Its Response To Nitrogen And Phosphate Availability, Fang Wei, Brian Fanella, Liang Guo, Xuemin Wang Jan 2016

Membrane Glycerolipidome Of Soybean Root Hairs And Its Response To Nitrogen And Phosphate Availability, Fang Wei, Brian Fanella, Liang Guo, Xuemin Wang

Biology Department Faculty Works

Root hairs are tubular extensions of specific root epidermal cells important in plant nutrition and water absorption. To determine membrane glycerolipids in root hairs and roots may differ, as well as their respective response to nutrient availability, this study analyzed the membrane glycerolipid species in soybean root hairs and in roots stripped of root hairs, and their response to nitrogen (N) and phosphate (Pi) supplementation. The ratio of phospholipids to galactolipids was 1.5 fold higher in root hairs than in stripped roots. Under Pi deficiency, the ratio of phospholipids to galactolipids in stripped roots decreased with the greatest decrease found …


Lineage Sorting In Multihost Parasites: Eidmanniella Albescens And Fregatiella Aurifasciata On Seabirds From The Galapagos Islands, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker Jan 2015

Lineage Sorting In Multihost Parasites: Eidmanniella Albescens And Fregatiella Aurifasciata On Seabirds From The Galapagos Islands, Jose Rivera-Parra, Iris Levin, Kevin Johnson, Patricia Parker

Biology Department Faculty Works

Parasites comprise a significant percentage of the biodiversity of the planet and are useful systems to test evolutionary and ecological hypotheses. In this study, we analyze the effect of host species identity and the immediate local species assemblage within mixed species colonies of nesting seabirds on patterns of genetic clustering within two species of multihost ectoparasitic lice. We use three genetic markers (one mitochondrial, COI, and two nuclear, EF1‐α and wingless) and maximum likelihood phylogenetic trees to test whether (1) parasites show lineage sorting based on their host species; and (2) switching of lineages to the alternate host species depends …


Allopolyploidy, Diversification, And The Miocene Grassland Expansion, Matt Estep, Michael Mckain, Dilys Diaz, Jinshun Zhong, John Hodge, Trevor Hodkinson, Daniel Layton, Simon Malcomber, Rémy Pasquet, Elizabeth Kellogg Oct 2014

Allopolyploidy, Diversification, And The Miocene Grassland Expansion, Matt Estep, Michael Mckain, Dilys Diaz, Jinshun Zhong, John Hodge, Trevor Hodkinson, Daniel Layton, Simon Malcomber, Rémy Pasquet, Elizabeth Kellogg

Biology Department Faculty Works

The role of polyploidy, particularly allopolyploidy, in plant diversification is a subject of debate. Whole-genome duplications precede the origins of many major clades (e.g., angiosperms, Brassicaceae, Poaceae), suggesting that polyploidy drives diversification. However, theoretical arguments and empirical studies suggest that polyploid lineages may actually have lower speciation rates and higher extinction rates than diploid lineages. We focus here on the grass tribe Andropogoneae, an economically and ecologically important group of C4 species with a high frequency of polyploids. A phylogeny was constructed for ca. 10% of the species of the clade, based on sequences of four concatenated low-copy nuclear loci. …


[Accepted Article Manuscript Version (Postprint)] Auxin Input Pathway Disruptions Are Mitigated By Changes In Auxin Biosynthetic Gene Expression In Arabidopsis, Gretchen Spiess, Amanda Hausman, Peng Yu, Jerry Cohen, Rebekah Rampey, Bethany Zolman Jul 2014

[Accepted Article Manuscript Version (Postprint)] Auxin Input Pathway Disruptions Are Mitigated By Changes In Auxin Biosynthetic Gene Expression In Arabidopsis, Gretchen Spiess, Amanda Hausman, Peng Yu, Jerry Cohen, Rebekah Rampey, Bethany Zolman

Biology Department Faculty Works

Auxin is a phytohormone involved in cell elongation and division. Levels of indole-3-acetic acid (IAA), the primary auxin, are tightly regulated through biosynthesis, degradation, sequestration, and transport. IAA is sequestered in reversible processes by adding amino acids, polyol or simple alcohols, or sugars, forming IAA conjugates, or through a two-carbon elongation forming indole-3-butyric acid. These sequestered forms of IAA alter hormone activity. To gain a better understanding of how auxin homeostasis is maintained, we have generated Arabidopsis (Arabidopsis thaliana) mutants that combine disruptions in the pathways, converting IAA conjugates and indole-3-butyric acid to free IAA. These mutants show phenotypes indicative …


Overexpression Of Patatin‐Related Phospholipase Aiii Δ Altered Plant Growth And Increased Seed Oil Content In Camelina, Xuemin Wang Jan 2014

Overexpression Of Patatin‐Related Phospholipase Aiii Δ Altered Plant Growth And Increased Seed Oil Content In Camelina, Xuemin Wang

Biology Department Faculty Works

Camelina sativa is a Brassicaceae oilseed species being explored as a biofuel and industrial oil crop. A growing number of studies have indicated that the turnover of phosphatidylcholine plays an important role in the synthesis and modification of triacylglycerols. This study manipulated the expression of a patatin‐related phospholipase AIIIδ (pPLAIII δ) in camelina to determine its effect on seed oil content and plant growth. Constitutive overexpression of pPLAIII δ under the control of the constitutive cauliflower mosaic 35S promoter resulted in a significant increase in seed oil content and a decrease in cellulose content. In addition, the content of major …


Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia Parker, Robert Ricklefs Jan 2014

Different Meal, Same Flavor: Cospeciation And Host Switching Of Haemosporidian Parasites In Some Non-Passerine Birds, Diego Santiago-Alarcon, Adriana Rodríguez-Ferraro, Patricia Parker, Robert Ricklefs

Biology Department Faculty Works

BackgroundPrevious studies have shown that haemosporidian parasites (Haemoproteus(Parahaemoproteus) and Plasmodium) infecting passerine birds have an evolutionary history of host switching with little cospeciation, in particular at low taxonomic levels (e.g., below the family level), which is suggested as the main speciation mechanism of this group of parasites. Recent studies have characterized diverse clades of haemosporidian parasites (H. (Haemoproteus) and H. (Parahaemoproteus)) infecting non-passerine birds (e.g., Columbiformes, Pelecaniiformes). Here, we explore the cospeciation history of H. (Haemoproteus) and H. (Parahaemoproteus) parasites with their non-passerine hosts.MethodsWe sequenced the mtDNA cyt b gene of both haemosporidian parasites and their avian non-passerine hosts. We …


Early Inflorescence Development In The Grasses (Poaceae), Elizabeth Kellogg, Paulo Camara, Paula Rudall, Philip Ladd, Simon Malcomber, Clinton Whipple, Andrew Doust Jul 2013

Early Inflorescence Development In The Grasses (Poaceae), Elizabeth Kellogg, Paulo Camara, Paula Rudall, Philip Ladd, Simon Malcomber, Clinton Whipple, Andrew Doust

Biology Department Faculty Works

The shoot apical meristem of grasses produces the primary branches of the inflorescence, controlling inflorescence architecture and hence seed production. Whereas leaves are produced in a distichous pattern, with the primordia separated from each other by an angle of 180◦, inflorescence branches are produced in a spiral in most species. The morphology and developmental genetics of the shift in phyllotaxis have been studied extensively in maize and rice. However, in wheat, Brachypodium, and oats, all in the grass subfamily Pooideae, the change in phyllotaxis does not occur; primary inflorescence branches are produced distichously. It is unknown whether the distichous inflorescence …


Patatin-Related Phospholipase Pplaiiiδ Increases Seed Oil Content With Long-Chain Fatty Acids In Arabidopsis, Maoyin Li, Sung Bahn, Chuchuan Fan, Jia Li, Tien Phan, Michael Ortiz, Mary Roth, Ruth Welti, Jan Jaworski, Xuemin Wang May 2013

Patatin-Related Phospholipase Pplaiiiδ Increases Seed Oil Content With Long-Chain Fatty Acids In Arabidopsis, Maoyin Li, Sung Bahn, Chuchuan Fan, Jia Li, Tien Phan, Michael Ortiz, Mary Roth, Ruth Welti, Jan Jaworski, Xuemin Wang

Biology Department Faculty Works

The release of fatty acids from membrane lipids has been implicated in various metabolic and physiological processes, but in many cases, the enzymes involved and their functions in plants remain unclear. Patatin-related phospholipase As (pPLAs) constitute a major family of acyl-hydrolyzing enzymes in plants. Here, we show that pPLAIIId promotes the production of triacylglycerols with 20- and 22-carbon fatty acids in Arabidopsis (Arabidopsis thaliana). Of the four pPLAIIIs (a, b, g, d), only pPLAIIId gene knockout results in a decrease in seed oil content, and pPLAIIId is most highly expressed in developing embryos. The overexpression of pPLAIIId increases the content …


Tcp Transcription Factor, Branch Angle Defective 1 (Bad1), Is Required For Normal Tassel Branch Angle Formation In Maize, Fang Bai, Renata Reinheimer, Diego Durantini, Elizabeth Kellogg, Robert Schmidt Jul 2012

Tcp Transcription Factor, Branch Angle Defective 1 (Bad1), Is Required For Normal Tassel Branch Angle Formation In Maize, Fang Bai, Renata Reinheimer, Diego Durantini, Elizabeth Kellogg, Robert Schmidt

Biology Department Faculty Works

In grass inflorescences, a structure called the “pulvinus” is found between the inflorescence main stem and lateral branches. The size of the pulvinus affects the angle of the lateral branches that emerge from the main axis and therefore has a large impact on inflorescence architecture. Through EMS mutagenesis we have identified three complementation groups of recessive mutants in maize having defects in pulvinus formation. All mutants showed extremely acute tassel branch angles accompanied by a significant reduction in the size of the pulvinus compared with normal plants. Two of the complementation groups correspond to mutations in the previously identified genes, …


Five Nuclear Loci Resolve The Polyploid History Of Switchgrass (Panicum Virgatum L.) And Relatives, Jimmy Triplett, Yunjing Wang, Jinshun Zhong, Elizabeth Kellogg Jun 2012

Five Nuclear Loci Resolve The Polyploid History Of Switchgrass (Panicum Virgatum L.) And Relatives, Jimmy Triplett, Yunjing Wang, Jinshun Zhong, Elizabeth Kellogg

Biology Department Faculty Works

Polyploidy poses challenges for phylogenetic reconstruction because of the need to identify and distinguish between homoeologous loci. This can be addressed by use of low copy nuclear markers. Panicum s.s. is a genus of about 100 species in the grass tribe Paniceae, subfamily Panicoideae, and is divided into five sections. Many of the species are known to be polyploids. The most well-known of the Panicum polyploids are switchgrass (Panicum virgatum) and common or Proso millet (P. miliaceum). Switchgrass is in section Virgata, along with P. tricholaenoides, P. amarum, and P. amarulum, whereas P. miliaceum is in sect. Panicum. We have …


[Accepted Article Manuscript Version (Postprint)] Pex5 Mutants That Differentially Disrupt Pts1 And Pts2 Peroxisomal Matrix Protein Import In Arabidopsis, Bibi Khan, Bethany Zolman Dec 2010

[Accepted Article Manuscript Version (Postprint)] Pex5 Mutants That Differentially Disrupt Pts1 And Pts2 Peroxisomal Matrix Protein Import In Arabidopsis, Bibi Khan, Bethany Zolman

Biology Department Faculty Works

PEX5 and PEX7 are receptors required for the import of peroxisome-bound proteins containing one of two peroxisomal targeting signals (PTS1 or PTS2). To better understand the role of PEX5 in plant peroxisomal import, we characterized the Arabidopsis (Arabidopsis thaliana) pex5-10 mutant, which has a T-DNA insertion in exon 5 of the PEX5 gene. Sequencing results revealed that exon 5, along with the T-DNA, is removed in this mutant, resulting in a truncated pex5 protein. The pex5-10 mutant has germination defects and is completely dependent on exogenous Suc for early seedling establishment, based on poor utilization of seed-storage fatty acids. This …


The Evolutionary History Of Ehrhartoideae, Oryzeae, And Oryza, Elizabeth Kellogg Jan 2009

The Evolutionary History Of Ehrhartoideae, Oryzeae, And Oryza, Elizabeth Kellogg

Biology Department Faculty Works

Rice is a member of the genus Oryza, which has a history extending back into the Miocene. Oryza is in turn a member of the tribe Oryzeae, which along with the tribe Ehrharteae is included in the subfamily Ehrhartoideae. This paper reviews current knowledge of the genus, tribe and subfamily, and places rice in the larger evolutionary context of the entire grass family. The morphological characteristics of rice are an amalgam of characters that have originated at different times in its long evolutionary history. Increasingly, genomic characteristics are also being placed in a broad evolutionary context and it is becoming …


The Plant Ontology Database: A Community Resource For Plant Structure And Developmental Stages Controlled Vocabulary And Annotations, Shulamit Avraham, Chih-Wei Tung, Katica Ilic, Pankaj Jaiswal, Elizabeth Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Rhee, Martin Sachs, Mary Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Felipe Zapata, Doreen Ware Jan 2008

The Plant Ontology Database: A Community Resource For Plant Structure And Developmental Stages Controlled Vocabulary And Annotations, Shulamit Avraham, Chih-Wei Tung, Katica Ilic, Pankaj Jaiswal, Elizabeth Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Rhee, Martin Sachs, Mary Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Felipe Zapata, Doreen Ware

Biology Department Faculty Works

The Plant Ontology Consortium (POC, http://www.plantontology.org ) is a collaborative effort among model plant genome databases and plant researchers that aims to create, maintain and facilitate the use of a controlled vocabulary (ontology) for plants. The ontology allows users to ascribe attributes of plant structure (anatomy and morphology) and developmental stages to data types, such as genes and phenotypes, to provide a semantic framework to make meaningful cross-species and database comparisons. The POC builds upon groundbreaking work by the Gene Ontology Consortium (GOC) by adopting and extending the GOC's principles, existing software and database structure. Over the past year, POC …


Conservation Of B Class Gene Expression In The Second Whorl Of A Basal Grass And Outgroups Links The Origin Of Lodicules And Petals, Clinton Whipple, Michael Zanis, Elizabeth Kellogg, Robert Schmidt Jan 2007

Conservation Of B Class Gene Expression In The Second Whorl Of A Basal Grass And Outgroups Links The Origin Of Lodicules And Petals, Clinton Whipple, Michael Zanis, Elizabeth Kellogg, Robert Schmidt

Biology Department Faculty Works

Studies of flower development in core eudicot species have established a central role for B class MADS-box genes in specifying petal and stamen identities. Similarly in maize and rice, B class genes are essential for lodicule and stamen specification, suggesting homology of petals and lodicules and conservation of B class gene activity across angiosperms. However, lodicules are grass-specific organs with a morphology distinct from petals, thus their true homology to eudicot and nongrass monocot floral organs has been a topic of debate. To understand the relationship of lodicules to the sterile floral organs of nongrass monocots we have isolated and …


The Plant Structure Ontology, A Unified Vocabulary Of Anatomy And Morphology Of A Flowering Plant, Katica Ilic, Elizabeth Kellogg, Pankaj Jaiswal, Felipe Zapata, Peter Stevens, Leszek Vincent, Shulamit Avraham, Leonore Reiser, Anuradha Pujar, Martin Sachs, Noah Whitman, Susan Mccouch, Mary Schaeffer, Doreen Ware, Lincoln Stein, Seung Rhee Dec 2006

The Plant Structure Ontology, A Unified Vocabulary Of Anatomy And Morphology Of A Flowering Plant, Katica Ilic, Elizabeth Kellogg, Pankaj Jaiswal, Felipe Zapata, Peter Stevens, Leszek Vincent, Shulamit Avraham, Leonore Reiser, Anuradha Pujar, Martin Sachs, Noah Whitman, Susan Mccouch, Mary Schaeffer, Doreen Ware, Lincoln Stein, Seung Rhee

Biology Department Faculty Works

Formal description of plant phenotypes and standardized annotation of gene expression and protein localization data require uniform terminology that accurately describes plant anatomy and morphology. This facilitates cross species comparative studies and quantitative comparison of phenotypes and expression patterns. A major drawback is variable terminology that is used to describe plant anatomy and morphology in publications and genomic databases for different species. The same terms are sometimes applied to different plant structures in different taxonomic groups. Conversely, similar structures are named by their species-specific terms. To address this problem, we created the Plant Structure Ontology (PSO), the first generic ontological …


Climatic Unpredictability And Parasitism Of Caterpillars: Implications Of Global Warming, John Stireman, Lee Dyer, D. Janzen, M. Singer, J. Lill, R. Marquis, R. Ricklefs, G. Gentry, W. Hallwachs, P. Coley, J. Barone, H. Greeney, H. Connahs, P. Barbosa, H. Morais, I. Diniz Nov 2005

Climatic Unpredictability And Parasitism Of Caterpillars: Implications Of Global Warming, John Stireman, Lee Dyer, D. Janzen, M. Singer, J. Lill, R. Marquis, R. Ricklefs, G. Gentry, W. Hallwachs, P. Coley, J. Barone, H. Greeney, H. Connahs, P. Barbosa, H. Morais, I. Diniz

Biology Department Faculty Works

Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar–parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps …


Plant Ontology (Po): A Controlled Vocabulary Of Plant Structures And Growth Stages, Pankaj Jaiswal, Shulamit Avraham, Katica Ilic, Elizabeth Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Rhee, Martin Sachs, Mary Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Doreen Ware, Felipe Zapata Jan 2005

Plant Ontology (Po): A Controlled Vocabulary Of Plant Structures And Growth Stages, Pankaj Jaiswal, Shulamit Avraham, Katica Ilic, Elizabeth Kellogg, Susan Mccouch, Anuradha Pujar, Leonore Reiser, Seung Rhee, Martin Sachs, Mary Schaeffer, Lincoln Stein, Peter Stevens, Leszek Vincent, Doreen Ware, Felipe Zapata

Biology Department Faculty Works

The Plant Ontology Consortium (POC) (www.plantontology.org) is a collaborative effort among several plant databases and experts in plant systematics, botany and genomics. A primary goal of the POC is to develop simple yet robust and extensible controlled vocabularies that accurately reflect the biology of plant structures and developmental stages. These provide a network of vocabularies linked by relationships (ontology) to facilitate queries that cut across datasets within a database or between multiple databases. The current version of the ontology integrates diverse vocabularies used to describe Arabidopsis, maize and rice (Oryza sp.) anatomy, morphology and growth stages. Using the ontology browser, …


Genetic Control Of Branching In Foxtail Millet, Andrew Doust, Katrien Devos, Michael Gadberry, Mike Gale, Elizabeth Kellogg Jun 2004

Genetic Control Of Branching In Foxtail Millet, Andrew Doust, Katrien Devos, Michael Gadberry, Mike Gale, Elizabeth Kellogg

Biology Department Faculty Works

Reduction in vegetative branching is commonplace when crops are domesticated from their wild progenitors. We have identified genetic loci responsible for these changes in foxtail millet (Setaria italica), a crop closely related to maize but whose genetics are little known. Quantitative trait locus (QTL) analysis and comparative genomics reveal that basal branching (tillering) and axillary branching are partially controlled by separate loci, and that the orthologue of teosinte branched1, the major gene controlling branching phenotype in maize, has only a minor and variable effect. We identify other candidate genes for control of branching, including a number of hormone biosynthesis pathway …


What Happens To Genes In Duplicated Genomes - With Correction, Elizabeth Kellogg Apr 2003

What Happens To Genes In Duplicated Genomes - With Correction, Elizabeth Kellogg

Biology Department Faculty Works

No abstract provided.


Tapeinosperma Alatum (Myrsinaceae): A Remarkable New Species From Ceram, Diane Holland, P.F. Stevens Jan 1998

Tapeinosperma Alatum (Myrsinaceae): A Remarkable New Species From Ceram, Diane Holland, P.F. Stevens

Biology Department Faculty Works

A new pachycaul species Tapeinosperma alatum D.E. Holland & P.F. Stevens (Myrsinaceae) is described from South Central Ceram. It is characterized by its huge leaves, over 1 m long, and congested, almost Gunnera-like. inflorescence. The distinctive distribution of the Papuasian pachycaul species of Tapeinosperma is briefly compared with that of a number of other unrelated taxa.


An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens Jan 1997

An Analysis Of The Variation Within Cratoxylum Arborescens (Clusiaceae) In Malesia, A.C. Church, P.F. Stevens

Biology Department Faculty Works

The variation within the widespread West Malesian species Cratoxylum arborescens (Vahl) Blume was analyzed and three distinctive variants were found. These are recognized formally as varieties, var. arborescens, var. miquelii King, and var. borneense A.C. Church & P.F. Stevens. A key and full descriptions are given. The characters employed to delimit the three taxa are discussed and the selection of varietal rank is justified.


A Second Nitrogenase In Vegetative Cells Of A Heterocyst-Forming Cyanobacterium, T Thiel, E Lyons, J Erker, A Ernst Sep 1995

A Second Nitrogenase In Vegetative Cells Of A Heterocyst-Forming Cyanobacterium, T Thiel, E Lyons, J Erker, A Ernst

Biology Department Faculty Works

In many filamentous cyanobacteria nitrogen fixation occurs in differentiated cells called heterocysts. Filamentous strains that do not form heterocysts may fix nitrogen in vegetative cells, primarily under anaerobic conditions. We describe here two functional Mo-dependent nitrogenases in a single organism, the cyanobacterium Anabaena variabilis. Using a lacZ reporter with a fluorescent beta-galactoside substrate for in situ localization of gene expression, we have shown that the two clusters of nif genes are expressed independently. One nitrogenase functions only in heterocysts under either aerobic or anaerobic growth conditions, whereas the second nitrogenase functions only under anaerobic conditions in vegetative cells and heterocysts. …