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

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

Peter Stevens

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 …


Cadherin-2 Participates In The Morphogenesis Of The Zebrafish Inner Ear, Sherry Babb-Clendenon, Yu-Chi Shen, Qin Liu, Katharyn E. Turner, M. Susan Mills, Greg W. Cook, Caroline A. Miller, Vincent H. Gattone Ii, Kate F. Barald, James A. Marrs Dec 2006

Cadherin-2 Participates In The Morphogenesis Of The Zebrafish Inner Ear, Sherry Babb-Clendenon, Yu-Chi Shen, Qin Liu, Katharyn E. Turner, M. Susan Mills, Greg W. Cook, Caroline A. Miller, Vincent H. Gattone Ii, Kate F. Barald, James A. Marrs

Qin Liu

Molecular mechanisms that control inner ear morphogenesis from the placode to the three-dimensional functional organ are not well understood. We hypothesize that cell-cell adhesion, mediated by cadherin molecules, contributes significantly to various stages of inner ear formation. Cadherin-2 (Cdh2) function during otic vesicle morphogenesis was investigated by examining morpholino antisense oligonucleotide knockdown and glass onion (glo) ( Cdh2 mutant) zebrafish embryos. Placode formation, vesicle cavitation and specification occurred normally, but morphogenesis of the otic vesicle was affected by Cdh2 deficiency: semicircular canals were reduced or absent. Phalloidin staining of the hair cell stereocillia demonstrated that cadherin-2 (cdh2) loss-of-function did not …


Quantitative Profiling Of Arabidopsis Polar Glycerolipids In Response To Phosphorus Starvation. Roles Of Phospholipases Dζ1 And Dζ2 In Phosphatidylcholine Hydrolysis And Digalactosyldiacylglycerol Accumulation In Phosphorus-Starved Plants, Xuemin Wang, Maoyin Li, Ruth Welti Sep 2006

Quantitative Profiling Of Arabidopsis Polar Glycerolipids In Response To Phosphorus Starvation. Roles Of Phospholipases Dζ1 And Dζ2 In Phosphatidylcholine Hydrolysis And Digalactosyldiacylglycerol Accumulation In Phosphorus-Starved Plants, Xuemin Wang, Maoyin Li, Ruth Welti

Xuemin (Sam) Wang

Phosphorus is an essential macronutrient that often limits plant growth and development. Under phosphorus-limited conditions, plants undergo substantial alterations in membrane lipid composition to cope with phosphorus deficiency. To characterize the changes in lipid species and to identify enzymes involved in plant response to phosphorus starvation, 140 molecular species of polar glycerolipids were quantitatively profiled in rosettes and roots of wild-type Arabidopsis (Arabidopsis thaliana) and phospholipase D knockout mutants pldζ1, pldζ2, and pldζ1pldζ2. In response to phosphorus starvation, the concentration of phospholipids was decreased and that of galactolipids was increased. Phospholipid lost in phosphorus-starved Arabidopsis rosettes was replaced by an …


The Localized Dynamics Of A Ca2+Channel (30-Minute Talk), Borbala Mazzag, Christoper Tignanelli, Gregory D. Smith Aug 2006

The Localized Dynamics Of A Ca2+Channel (30-Minute Talk), Borbala Mazzag, Christoper Tignanelli, Gregory D. Smith

Borbala Mazzag

No abstract provided.


Unraveling The Mechanical Properties Of Composite Silk Threads Spun By Cribellate Orb-Weaving Spiders, Todd Blackledge, Cheryl Hayashi Aug 2006

Unraveling The Mechanical Properties Of Composite Silk Threads Spun By Cribellate Orb-Weaving Spiders, Todd Blackledge, Cheryl Hayashi

Todd A. Blackledge

Orb-web weaving spiders depend upon the mechanical performance of capture threads to absorb the energy of flying prey. Most orb-weavers spin wet capture threads with core fibers of flagelliform silk. These threads are extremely compliant and extensible due to the folding of their constituent proteins into molecular nanosprings and hydration by a surrounding coating of aqueous glue. In contrast, other orb-weavers use cribellate capture threads, which are composite structures consisting of core fibers of pseudoflagelliform silk surrounded by a matrix of fine dry cribellar fibrils. Based on phylogenetic evidence, cribellate capture threads predate the use of viscid capture threads. To …


Evaluating The Monophyly Of Eulimnadia And The Limnadiinae (Branchiopoda : Spinicaudata) Using Dna Sequences, W. R. Hoeh, N. D. Smallwood, D. M. Senyo, E. G. Chapman, Stephen C. Weeks Apr 2006

Evaluating The Monophyly Of Eulimnadia And The Limnadiinae (Branchiopoda : Spinicaudata) Using Dna Sequences, W. R. Hoeh, N. D. Smallwood, D. M. Senyo, E. G. Chapman, Stephen C. Weeks

Stephen C. Weeks

The evolutionary relationships among the six nominal genera within the spinicaudate clam shrimp family Limnadiidae, as well as the validity of the limnadiid genus Eulimnadia, have been much debated in the literature with little consensus emerging. The lack of resolution on these topics impedes evaluations of limnadiid biodiversity, phylogeny, and character evolution. To address these issues, we used Bayesian and parsimony methods to analyze DNA sequences from three genetic loci (28S, 12S, cytb) that were obtained from representatives of five nominal limnadiid genera and one undescribed limnadiid species. These analyses confirm the monophyly of Eulimnadia and the most taxonomically inclusive …


Homeland Security: Engaging The Frontlines - Symposium Proceedings, George H. Baker, Cheryl J. Elliott Apr 2006

Homeland Security: Engaging The Frontlines - Symposium Proceedings, George H. Baker, Cheryl J. Elliott

George H Baker

The rise of the American homeland security endeavor under the leadership of the new Department of Homeland Security has been heralded by several major national strategy documents. These documents have served to organize efforts at top levels within the government and industry. However, the national strategy guidance is not getting to many organizations and people at the grass-roots level who can make the most difference in preventing attacks, protecting systems, and recovering from catastrophic events, viz. the general citizenry, private infrastructure owners, and local governments. To better understand grass-roots issues and solutions, James Madison University, in cooperation with the Federal …


A Subset Of Mer1p-Dependent Introns Requires Bud13p For Splicing Activation And Nuclear Retention, Marc Spingola, Frederick W. Scherrer Jr Apr 2006

A Subset Of Mer1p-Dependent Introns Requires Bud13p For Splicing Activation And Nuclear Retention, Marc Spingola, Frederick W. Scherrer Jr

Marc Spingola

In the yeast Saccharomyces cerevisiae, Mer1p is expressed only during meiosis, and its expression is linked to the splicing of at least three mRNAs: MER2, MER3, and AMA1. Previous evidence suggests that Mer1p activates splicing by directly recruiting snRNPs or stabilizing intermediate splicing complexes formed on pre-mRNA that contains an intronic Mer1p enhancer element. However, some splicing factors, especially accessory/non-snRNP factors, have critical roles in retaining unspliced pre-mRNAs in the nucleus. We tested if Mer1p may indirectly regulate splicing by preventing the export of pre-mRNAs to the cytoplasm and also demonstrated that a second subunit of the Retention and Splicing …


Phylogeography Of The Flag Cabrilla Epinephelus Labriformis (Serranidae): Implications For The Biogeography Of The Tropical Eastern Pacific And The Early Stages Of Speciation In A Marine Shore Fish, Mathew T. Craig, Phillip A. Hastings, Daniel J. Pondella Ii, D. Ross Robertson, Jorge A. Rosales-Casián Mar 2006

Phylogeography Of The Flag Cabrilla Epinephelus Labriformis (Serranidae): Implications For The Biogeography Of The Tropical Eastern Pacific And The Early Stages Of Speciation In A Marine Shore Fish, Mathew T. Craig, Phillip A. Hastings, Daniel J. Pondella Ii, D. Ross Robertson, Jorge A. Rosales-Casián

Daniel Pondella

To examine the role of previously described biogeographical boundaries in shaping phylogeographical relationships within and among two putative eastern Pacific sibling species, the flag cabrilla, Epinephelus labriformis and the Clipperton grouper, Epinephelus clippertonensis (Serranidae).


Rapid Signaling At The Plasma Membrane By A Nuclear Receptor For Thyroid Hormone, Hemayet Ullah Feb 2006

Rapid Signaling At The Plasma Membrane By A Nuclear Receptor For Thyroid Hormone, Hemayet Ullah

Hemayet Ullah

Many nuclear hormones have physiological effects that are too rapid to be explained by changes in gene expression and are often attributed to unidentified or novel G protein-coupled receptors. Thyroid hormone is essential for normal human brain development, but the molecular mechanisms responsible for its effects remain to be identified. Here, we present direct molecular evidence for potassium channel stimulation in a rat pituitary cell line (GH(4)C(1)) by a nuclear receptor for thyroid hormone, TRbeta, acting rapidly at the plasma membrane through phosphatidylinositol 3-kinase (PI3K) to slow the deactivation of KCNH2 channels already in the membrane. Signaling was disrupted by …


Littoral Benthic Marcroinvertebrates Under Contrasting Drawdown In A Reservoir And A Natural Lake, Paula Furey, Rick N. Nordin, Asit Mazumder Feb 2006

Littoral Benthic Marcroinvertebrates Under Contrasting Drawdown In A Reservoir And A Natural Lake, Paula Furey, Rick N. Nordin, Asit Mazumder

Paula Furey

No abstract provided.


Longitudinal Changes In Visual Acuity In Keratoconus, Larry J. Davis, Kenneth B. Schechtman, Brad S. Wilson, Carol E. Rosenstiel, Colleen H. Riley, David P. Libassi, Ralph E. Gundel, Louis Rosenberg, Mae O. Gordon, Karla Zadnik Jan 2006

Longitudinal Changes In Visual Acuity In Keratoconus, Larry J. Davis, Kenneth B. Schechtman, Brad S. Wilson, Carol E. Rosenstiel, Colleen H. Riley, David P. Libassi, Ralph E. Gundel, Louis Rosenberg, Mae O. Gordon, Karla Zadnik

Larry Davis

Purpose.
The present investigation aimed to identify factors that predict reduced visual acuity in keratoconus from a prospective, longitudinal study.

Methods.
This report from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study used 7 years of follow-up data from 953 CLEK subjects who did not have penetrating keratoplasty in either eye at baseline and who provided enough data to compute the slope of the change over time in high- or low-contrast best-corrected visual acuity (BCVA). Outcome measures included these slopes and whether the number of letters correctly read decreased by 10 letters or more in at least one eye in …


Double Knockouts Of Phospholipases Dζ1 And Dζ2 In Arabidopsis Affect Root Elongation During Phosphate-Limited Growth But Do Not Affect Root Hair Patterning, Xuemin Wang, Maoyin Li, Chunbo Qin, Ruth Welti Jan 2006

Double Knockouts Of Phospholipases Dζ1 And Dζ2 In Arabidopsis Affect Root Elongation During Phosphate-Limited Growth But Do Not Affect Root Hair Patterning, Xuemin Wang, Maoyin Li, Chunbo Qin, Ruth Welti

Xuemin (Sam) Wang

Root elongation and root hair formation are important in nutrient absorption. We found that two Arabidopsis (Arabidopsis thaliana) phospholipase Ds (PLDs), PLDζ1 and PLDζ2, were involved in root elongation during phosphate limitation. PLDζ1 and PLDζ2 are structurally different from the majority of plant PLDs by having phox and pleckstrin homology domains. Both PLDζs were expressed more in roots than in other tissues. It was reported previously that inducible suppression or inducible overexpression of PLDζ1 affected root hair patterning. However, gene knockouts of PLDζ1, PLDζ2, or the double knockout of PLDζ1 and PLDζ2 showed no effect on root hair formation. The …


Variation In The Innate And Acquired Arms Of The Immune System Among Five Shorebird Species, Luisa Mendes, Theunis Piersma, Dennis Hasselquist, Kevin D. Matson, Robert E. Ricklefs Jan 2006

Variation In The Innate And Acquired Arms Of The Immune System Among Five Shorebird Species, Luisa Mendes, Theunis Piersma, Dennis Hasselquist, Kevin D. Matson, Robert E. Ricklefs

Robert Ricklefs

To contribute to an understanding of the evolutionary processes that shape variation in immune responses, we compared several components of the innate and acquired arms of the immune system in five related, but ecologically diverse, migratory shorebirds (ruff Philomachus pugnax L., ruddy turnstone Arenaria interpres L., bar-tailed godwit Limosa lapponica L., sanderling Calidris alba Pallas and red knotC. canutus L.). We used a hemolysis-hemagglutination assay in free-living shorebirds to assess two of the innate components (natural antibodies and complement-mediated lysis), and a modified quantitative enzyme-linked immunosorbent assay in birds held in captivity to assess the acquired component (humoral antibodies …


Purple Loosestrife On The Susquehanna River’S West Branch: Distribution And Environmental Correlates, E. Ketterer, Warren Abrahamson Dec 2005

Purple Loosestrife On The Susquehanna River’S West Branch: Distribution And Environmental Correlates, E. Ketterer, Warren Abrahamson

Warren G. Abrahamson, II

No abstract provided.


African-American Mitochondrial Dnas Often Match Mtdnas Found In Multiple African Ethnic Groups [Published Correction Appears In Bmc Biol 2006; 5:13], Bert Ely, Jamie L. Wilson, Fatimah Linda Collier Jackson, Bruce A. Jackson Dec 2005

African-American Mitochondrial Dnas Often Match Mtdnas Found In Multiple African Ethnic Groups [Published Correction Appears In Bmc Biol 2006; 5:13], Bert Ely, Jamie L. Wilson, Fatimah Linda Collier Jackson, Bruce A. Jackson

Fatimah Linda Collier Jackson

Mitochondrial DNA (mtDNA) haplotypes have become popular tools for tracing maternal ancestry, and several companies offer this service to the general public. Numerous studies have demonstrated that human mtDNA haplotypes can be used with confidence to identify the continent where the haplotype originated. Ideally, mtDNA haplotypes could also be used to identify a particular country or ethnic group from which the maternal ancestor emanated. However, the geographic distribution of mtDNA haplotypes is greatly influenced by the movement of both individuals and population groups. Consequently, common mtDNA haplotypes are shared among multiple ethnic groups. We have studied the distribution of mtDNA …


Rack1 Mediates Multiple Hormone Responsiveness And Developmental Processes In Arabidopsis, Hemayet Ullah Dec 2005

Rack1 Mediates Multiple Hormone Responsiveness And Developmental Processes In Arabidopsis, Hemayet Ullah

Hemayet Ullah

The scaffold protein RACK1 (Receptor for Activated C Kinase 1) serves as an integrative point for diverse signal transduction pathways. The Arabidopsis genome contains three RACK1 orthologues, however, little is known about their functions. It is reported here that one member
of this gene family, RACK1A, previously identified as the Arabidopsis homologue of the tobacco arcA gene, mediates hormone responses and plays a regulatory role in multiple developmental processes. RACK1A expresses ubiquitously in Arabidopsis. Loss-of-function mutations in RACK1A confer defects in multiple developmental processes including seed germination, leaf production, and flowering. rack1a mutants displayed reduced sensitivity to gibberellin and brassinosteroid …


Identification And Characterization Of A New Class Of Bilin Lyase Responsible For Attachment Of Phycocyanobilin To Cys-153 On The Β-Subunit Of Phycocyanin In Synechococcus Sp. Pcc 7002, Wendy M. Schluchter Dec 2005

Identification And Characterization Of A New Class Of Bilin Lyase Responsible For Attachment Of Phycocyanobilin To Cys-153 On The Β-Subunit Of Phycocyanin In Synechococcus Sp. Pcc 7002, Wendy M. Schluchter

Wendy M Schluchter

No abstract provided.


Molecular Detection Of Marine Invertebrate Larvae, Shana Goffredi, William J. Jones, Christopher A. Scholin, Roman Marin Iii, Robert C. Vrijenhoek Dec 2005

Molecular Detection Of Marine Invertebrate Larvae, Shana Goffredi, William J. Jones, Christopher A. Scholin, Roman Marin Iii, Robert C. Vrijenhoek

Shana Goffredi

The ecological patterns of many invertebrate larvae remain an ongoing mystery, in large part owing to the difficult task of detecting them in the water column. The development of nucleic-acid-based technology has the potential to resolve this issue by direct identification and monitoring of embryonic and larval forms in situ. We report herein on the successful development and application of nucleic-acid-based sandwich hybridization assays that detect barnacles using rRNA-targeted probes with both group-(order Thoracica) and species-(Balanus glandula) specificity. Primary results include the determination of target 18S rRNA sequences and the construction of "capture" probes for detection of larvae using hybridization …


Silken Toolkits: Biomechanics Of Silk Fibers Spun By The Orb Web Spider Argiope Argentata (Fabricius 1775), Todd A. Blackledge, Cheryl Y. Hayashi Dec 2005

Silken Toolkits: Biomechanics Of Silk Fibers Spun By The Orb Web Spider Argiope Argentata (Fabricius 1775), Todd A. Blackledge, Cheryl Y. Hayashi

Todd A. Blackledge

Orb-weaving spiders spin five fibrous silks from differentiated glands that contain unique sets of proteins. Despite diverse ecological functions, the mechanical properties of most of these silks are not well characterized. Here, we quantify the mechanical performance of this toolkit of silks for the silver garden spider Argiope argentata. Four silks exhibit viscoelastic behaviour typical of polymers, but differ statistically from each other by up to 250% in performance, giving each silk a distinctive suite of material properties. Major ampullate silk is 50% stronger than other fibers, but also less extensible. Aciniform silk is almost twice as tough as other …


Ethnic Identity And Type 2 Diabetes Health Attitudes In Americans Of African Ancestry, Jelena Brezo, Charmaine D. Royal, Franklin Ampy, Verle Headings Dec 2005

Ethnic Identity And Type 2 Diabetes Health Attitudes In Americans Of African Ancestry, Jelena Brezo, Charmaine D. Royal, Franklin Ampy, Verle Headings

Franklin Ampy

Background: Exploring the role of ethnic identity may be a good starting point toward a better understanding of health attitudes in different communities. This knowledge would be most useful in addressing diseases that cause significant burden and for which known prevention and morbidity-reducing strategies are effective.
Objective: The main objective was to investigate possible associations between measures of ethnic identity and health attitudes toward type 2 diabetes mellitus by using a questionnaire-based measure.


Laboratory Bioefficacy Of Creek 1.0g (Tentephos) Against Aedes (Stegomyia) Aegypti (Linnaeus) Lairvae, Chen Chee Dhang Dec 2005

Laboratory Bioefficacy Of Creek 1.0g (Tentephos) Against Aedes (Stegomyia) Aegypti (Linnaeus) Lairvae, Chen Chee Dhang

Chen Chee Dhang

The bioefficacy of a commercial formulation of temephos, Creek((R)) againstAedes aegypti larvae was studied in the laboratory. Earthen jars were filled with 10 L tap water each. One g of temephos (Creek((R))) sand granule formulation was added into each earthen jar as recommended by the manufacturer. The final test concentration of Creek((R)) was 1 mg ai./L One earthen jar was filled with 10 L tap water and served as a test control (untreated). Thirty late 3(rd) or early 4(th) instar of lab-bred Ae. aegypti larvae were added into each earthen jar. Mortality of the larvae was recorded after 24 hours …


Female Preferences For Male Calling Songs In The Bladder Grasshopper Bullacris Membracioides, Vanessa C. K. Couldridge, Moira J. Van Staaden Dec 2005

Female Preferences For Male Calling Songs In The Bladder Grasshopper Bullacris Membracioides, Vanessa C. K. Couldridge, Moira J. Van Staaden

Moira J. van Staaden

Male acoustic signals and the information they convey are often critical determinants of female mate choice. Bladder grasshoppers are one of numerous orthopteran taxa utilizing sound as the basis of courtship and ultimately mating. However, despite the extreme specializations for long-distance acoustic communication in this family, female mating preferences for male calls have not been previously investigated. Here we examine female acoustic responses to playbacks of male calls in Bullacris membracioides. Females were tested in three separate contexts, viz. response to conspecific calls of different individuals, response to degraded conspecific calls, and response to the calls of two heterospecifics. Female …


The Use Of The Major Chelae By Reproductive Male Crayfish (Orconectes Rusticus) For Discrimination Of Female Odours, Rachelle M. Belanger, Paul A. Moore Dec 2005

The Use Of The Major Chelae By Reproductive Male Crayfish (Orconectes Rusticus) For Discrimination Of Female Odours, Rachelle M. Belanger, Paul A. Moore

Paul A. Moore

The major chelae have been found to be important structures used for breeding and reproduction in crustaceans; however their role in the detection of conspecific sex odours is unknown. We implemented a behavioural bioassay to test whether male reproductive (form I) and nonreproductive (form II) crayfish (Orconectes rusticus) use their major chelae to detect reproductive female odours. We videotaped and analysed the behavioural reactions of form I and form II males to four different odour treatments: reproductive female-conditioned water, male-conditioned water, filtered fish homogenate (food odour; positive control), and water (negative control) delivered from an air stone (N = 20 …


Evaluation Of Eelgrass Mitigation And Fishery Enhancement Structures In San Diego Bay, California, Daniel Pondella Ii Dec 2005

Evaluation Of Eelgrass Mitigation And Fishery Enhancement Structures In San Diego Bay, California, Daniel Pondella Ii

Daniel Pondella

To offset habitat loss and increase fishery production, an eelgrass mitigation habitat was completed in San Diego Bay, California in 1997. This mitigation effort consisted of the transplantation of eelgrass, Zostera marina L., in the western portion of the bay. In addition to the establishment of a new eelgrass bed, four enhancement reefs made of either quarry rock or concrete rubble were created to further enhance fishery stocks and the area's ecosystem. Two design criteria and a direct comparison between quarry rock and concrete reefs were examined in this 5-yr pilot program. The newly created eelgrass habitat quickly performed at …


Conservation Medicine On The Galápagos Islands: Partnerships Among Behavioral, Population, And Veterinary Scientists, Patricia G. Parker, Noah Kerness Whiteman, R. Eric Miller Dec 2005

Conservation Medicine On The Galápagos Islands: Partnerships Among Behavioral, Population, And Veterinary Scientists, Patricia G. Parker, Noah Kerness Whiteman, R. Eric Miller

Patricia Parker

No abstract provided.


Absence Of Spiroplasma Or Other Bacterial 16s Rrna Genes In Brain Tissue Of Hamsters With Scrapie, Irina Alexeeva, Ellen J. Elliott, Sandra Rollins, Gail E. Gasparich, Jozef Lazar, Robert G. Rohwer Dec 2005

Absence Of Spiroplasma Or Other Bacterial 16s Rrna Genes In Brain Tissue Of Hamsters With Scrapie, Irina Alexeeva, Ellen J. Elliott, Sandra Rollins, Gail E. Gasparich, Jozef Lazar, Robert G. Rohwer

Gail Gasparich

Spiroplasma spp. have been proposed to be the etiological agents of the transmissible spongiform encephalopathies (TSEs). In a blind study, a panel of 20 DNA samples was prepared from the brains of uninfected hamsters or hamsters infected with the 263K strain of scrapie. The brains of the infected hamsters contained ≥1010 infectious doses/g. The coded panel was searched for bacterial 16S rRNA gene sequences, using primers selective for spiroplasma sequences, primers selective for mollicutes in general, and universal bacterial primers. After 35 PCR cycles, no samples were positive for spiroplasma or any other bacterial DNA, while control Spiroplasma mirum genomic …


Multiple Sequence Alignment Accuracy And Phylogenetic Inference, T. Heath Ogden Dec 2005

Multiple Sequence Alignment Accuracy And Phylogenetic Inference, T. Heath Ogden

T. Heath Ogden

Phylogenies are often thought to be more dependent upon the specifics of the sequence alignment rather than on the method of reconstruction. Simulation of sequences containing insertion and deletion events was performed in order to determine the role that alignment accuracy plays during phylogenetic inference. Data sets were simulated for pectinate, balanced, and random tree shapes under different conditions (ultrametric equal branch length, ultrametric random branch length, nonultrametric random branch length). Comparisons between hypothesized alignments and true alignments enabled determination of two measures of alignment accuracy, that of the total data set and that of individual branches. In general, our …