Life Sciences Commons^™

Gene Response Profiles For Daphnia Pulex Exposed To The Environmental Stressor Cadmium Reveals Novel Crustacean Metallothioneins, Joseph R. Shaw, John K. Colbourne, Jennifer C. Davey, Stephen P. Glaholt, Thomas H. Hampton, Celia Y. Chen, Carol L. Folt, Joshua W. Hamilton

Dartmouth Scholarship

Genomic research tools such as microarrays are proving to be important resources to study the complex regulation of genes that respond to environmental perturbations. A first generation cDNA microarray was developed for the environmental indicator species Daphnia pulex, to identify genes whose regulation is modulated following exposure to the metal stressor cadmium. Our experiments revealed interesting changes in gene transcription that suggest their biological roles and their potentially toxicological features in responding to this important environmental contaminant.

Systematics Of Bromelioideae (Bromeliaceae)—Evidence From Molecular And Anatomical Studies, Ralf Horres, Katharina Schulte, Kurt Weising, Georg Zizka

Aliso: A Journal of Systematic and Floristic Botany

A reconstruction of the phylogeny of Bromeliaceae based on sequence data from three noncoding chloroplast DNA markers (trnL intron, trnT–trnL, and trnT–trnF intergenic spacer [IGS]) is presented, including 26 genera and 33 species. Relationships of Bromelioideae and phylogeny within this subfamily were analyzed in more detail on the basis of two of these markers (trnL intron and trnL–trnF IGS) using a set of 37 genera/74 species of Bromeliaceae, including 28 genera/60 species of Bromelioideae. Sister group relationships of Bromelioideae were not resolved with sufficient reliability, but the …

Phylogeny Of Cyperaceae Based On Dna Sequence Data–A New Rbcl Analysis, David A. Simpson, A. Muthama Muasya, Marccus V. Alves, Jeremy J. Bruhl, Sandra Dhooge, Mark W. Chase, Carol A. Furness, Kioumars Ghamkhar, Paul Goetghebeur, Trevor R. Hodkinson, Adam D. Marchant, Anton A. Reznicek, Roland Nieuwborg, Eric H. Roalson, Erik Smets, Julian R. Starr, William W. Thomas, Karen L. Wilson, Xiufu Zhang

Aliso: A Journal of Systematic and Floristic Botany

Since the Monocots II meeting in 1998, significant new data have been published that enhance our systematic knowledge of Cyperaceae. Phylogenetic studies in the family have also progressed steadily. For this study, a parsimony analysis was carried out using all rbcL sequences currently available for Cyperaceae, including data for two new genera. One of the four subfamilies (Caricoideae) and seven of the 14 tribes (Bisboeckelereae, Cariceae, Cryptangieae, Dulichieae, Eleocharideae, Sclerieae, Trilepideae) are monophyletic. Subfamily Mapanioideae and tribe Chrysitricheae are monophyletic if, as the evidence suggests, Hellmuthia is considered a member of Cypereae. Some other features of our analysis include: …

Phylogeny Of Abildgaardieae (Cyperaceae) Inferred From Its And Trnl–F Data, Kioumars Ghamkhar, Adam D. Marchant, Karen L. Wilson, Jeremy J. Bruhl

Aliso: A Journal of Systematic and Floristic Botany

Within the tribe Abildgaardieae, the relationships between Fimbristylis and its relatives have not been certain, and the limits of Fimbristylis have been unclear, with Bulbostylis and Abildgaardia variously combined with it and each other. The relationships and limits of tribes Abildgaardieae and Arthrostylideae and their genera were evaluated across 49 representative species using parsimony and maximum likelihood analyses of ITS (nuclear ribosomal) and trnL–F (plastid) DNA sequence data separately and combined. The evolutionary reconstructions derived from sequences of cpDNA and nrDNA disagree about the position of tribe Arthrostylideae relative to Abildgaardieae; Arthrostylis and Actinoschoenus are either nested within Abildgaardieae …

Phylogenetic Relationships In Tribe Cariceae (Cyperaceae) Based On Nested Analyses Of Four Molecular Data Sets, Marcia J. Waterway, Julian R. Starr

Aliso: A Journal of Systematic and Floristic Botany

Phylogenetic reconstruction for Carex and relatives in tribe Cariceae is complicated by species richness and nearly cosmopolitan distribution. In this investigation, our main objective was to estimate evolutionary relationships in tribe Cariceae using DNA sequence data from two spacer regions in nuclear ribosomal genes (ITS and ETS-1f) combined with noncoding chloroplast DNA (trnL intron, trnL–trnF intergenic spacer, and trnE–trnD intergenic spacers). Parsimony analyses of separate and combined data and Bayesian analysis of the combined data matrix revealed strong support for monophyly of tribe Cariceae and for monophyly of two major lineages, one …

Phylogeny Of The Grasses (Poaceae) Revisited, Melvin R. Duvall, Jerrold I Davis, Lynn G. Clark, Jeffrey D. Noll, Douglas H. Goldman, J. Gabriel Sánchez-Ken

Aliso: A Journal of Systematic and Floristic Botany

The most robust previously published phylogeny for the overall structure of the grass family (Poaceae) shows three early diverging lineages and two major derived clades, the BEP clade and the PACCAD clade (Grass Phylogeny Working Group 2001). A few key taxa were incompletely sampled, however, and support for the BEP clade was moderate at best and relationships among the major lineages within the PACCAD clade remained unresolved. In addition, recent studies indicated that the sister group to Poaceae may be Joinvilleaceae and/or Ecdeiocoleaceae, the latter of which were not previously sampled. In this study, missing structural data were determined and …

Phylogeny Of Triticeae (Poaceae) Based On Three Organelle Genes, Two Single-Copy Nuclear Genes, And Morphology, Ole Seberg, Gitte Petersen

Aliso: A Journal of Systematic and Floristic Botany

Triticeae are renowned for their complicated taxonomy, but their phylogeny is equally intricate and perplexing, and remains largely unresolved. Based on morphology and nucleotide sequences from two plastid genes (rbcL, rpoA), one mitochondrial gene (coxII), and two single-copy nuclear genes (DMC1, EF-G), the most comprehensive hypothesis (both with respect to taxa and data points) of the phylogeny of diploid Triticeae to date is presented. The incongruence length difference tests clearly indicate that the four logical data partitions (morphology and the three genome compartments) are mutually incongruent, except the mitochondrial and nuclear sequences. …

Phylogenetics Of Andropogoneae (Poaceae: Panicoideae) Based On Nuclear Ribosomal Internal Transcribed Spacer And Chloroplast Trnl–F Sequences, Elizabeth M. Skendzic, J. Travis Columbus, Rosa Cerros-Tlatilpa

Aliso: A Journal of Systematic and Floristic Botany

Phylogenetic relationships among 85 species representing 35 genera in the grass tribe Andropogoneae were estimated from maximum parsimony and Bayesian analyses of nuclear ITS and chloroplast trnL–F DNA sequences. Ten of the 11 subtribes recognized by Clayton and Renvoize (1986) were sampled. Independent analyses of ITS and trnL–F yielded mostly congruent, though not well resolved, topologies. Arundinella is sister to Andropogoneae in the trnL–F phylogeny and is nested within the tribe in the ITS and combined data trees. Tristachya is sister to Andropogoneae + Arundinella in the ITS phylogeny. Four clades are common to the ITS and …

Phylogenetic Relationships Of The Decumbentes Group Of Paspalum, Thrasya, And Thrasyopsis (Poaceae: Panicoideae: Paniceae), Silvia S. Denham, Fernando O. Zuloaga

Aliso: A Journal of Systematic and Floristic Botany

Paspalum (Poaceae: Panicoideae: Paniceae) includes 330 species distributed mainly in tropical and subtropical regions of America. Due to the large number of species and convergence in many characters, an adequate infrageneric classification is still needed. Studies on Paniceae based on molecular and morphological data have suggested that Paspalum is paraphyletic, including the genus Thrasya, but none of these analyses have included a representative sample of these two genera. In this study, phylogenetic relationships among the informal group Decumbentes of Paspalum, plus subgenera and other informal groups, and the genera Thrasya and Thrasyopsis were estimated. A cladistic analysis under …

Phylogenetics Of Chloridoideae (Gramineae): A Preliminary Study Based On Nuclear Ribosomal Internal Transcribed Spacer And Chloroplast Trnl–F Sequences, J. Travis Columbus, Rosa Cerros-Tlatilpa, Michael S. Kinney, Maria Elena Siqueiros-Delgado, Hester L. Bell, M. Patrick Griffith, Nancy F. Refulio-Rodriguez

Aliso: A Journal of Systematic and Floristic Botany

The phylogeny of Chloridoideae (Gramineae) was inferred from parsimony analyses of DNA sequences from two genomes—the chloroplast trnL intron, trnL 3' exon, and trnL–F intergenic spacer, and the nuclear ribosomal internal transcribed spacer region (ITS1 + 5.8S + ITS2). Eighty species representing 66 chloridoid genera were sampled, including all but four of the native New World genera. Analyses of the individual and combined data sets were performed. The phylogenies were found to be highly congruent. Of the four tribes and seven subtribes of Chloridoideae sensu Clayton and Renvoize (1986) whose phylogenetic status could be tested with our …

Phylogenetic Relationships Among The One-Flowered, Determinate Genera Of Bambuseae (Poaceae: Bambusoideae), Lynn G. Clark, Soejatmi Dransfield, Jimmy Triplett, J. Gabriel Sánchez-Ken

Aliso: A Journal of Systematic and Floristic Botany

Bambuseae (woody bamboos), one of two tribes recognized within Bambusoideae (true bamboos), comprise over 90% of the diversity of the subfamily, yet monophyly of the tribe is generally only moderately supported, and phylogenetic relationships within the tribe are poorly understood. In addition, there appears to be some level of conflict between morphological and molecular data within the tribe. We conducted a parsimony analysis of 43 species of Bambuseae, three of Olyreae (herbaceous bamboos), and two outgroup taxa using morphological and plastid rpl16 intron sequence data to (1) further test the monophyly of Bambuseae, (2) test the monophyly of Chusqueinae …

Phylogeny And Biogeography Of Endemic Festuca (Poaceae) From New Zealand Based On Nuclear (Its) And Chloroplast (Trnl–Trnf) Nucleotide Sequences, Kelvin M. Lloyd, Angela M. Hunter, David A. Orlovich, Suzanne J. Draffin, Alan V. Stewart, William G. Lee

Aliso: A Journal of Systematic and Floristic Botany

We investigated the phylogenetic relationships of the endemic New Zealand (NZ) species of Festuca (Poaceae, Pooideae) by assessing sequence variation from the nuclear internal transcribed spacers (ITS) and a chloroplast intergenic spacer (trnL–trnF) and by measuring DNA content using flow cytometry. The ITS and trnL–trnF data sets were congruent in showing that the NZ species of Festuca have two origins. One group, containing F. coxii, F. luciarum, F. multinodis, and F. ultramafica, is closely related to Festuca sect. Aulaxyper. The other group includes a clade of five endemic …

Jhe In Gryllus Assimilis: Cloning, Sequence-Activity Associations And Phylogeny, E. J. Crone, Anthony J. Zera, A. Anand, J. G. Oakeshott, T. D. Sutherland, R. J. Russell, Lawrence G. Harshman, Federico G. Hoffmann, C. Claudianos

Anthony Zera Publications

The 458 amino acid sequence of a mature JHE protein from the cricket Gryllus assimilis was identified after isolating the partial cDNA sequence encoding this protein from a fat body and midgut cDNA library. This hemimetabolan JHE sequence shows over 40% amino acid similarity to the known JHE sequences of several holometabolous insects. It also includes previously determined peptide sequences for G. assimilis JHE as well as two other motifs associated with JHE enzymes in holometabolous insects. The predicted molecular weight of the protein agrees with that of the JHE previously purified from G. assimilis. Partial genomic sequence encoding …

The Kinesin-13 Proteins Kif2a, Kif2b, And Kif2c/Mcak Have Distinct Roles During Mitosis In Human Cells, Amity L. Manning, Neil J. Ganem, Samuel F. Bakhoum, Michael Wagenbach, Linda Wordeman, Duane A. Compton

Dartmouth Scholarship

The human genome has three unique genes coding for kinesin-13 proteins called Kif2a, Kif2b, and MCAK (Kif2c). Kif2a and MCAK have documented roles in mitosis, but the function of Kif2b has not been defined. Here, we show that Kif2b is expressed at very low levels in cultured cells and that GFP-Kif2b localizes predominately to centrosomes and midbodies, but also to spindle microtubules and transiently to kinetochores. Kif2b-deficient cells assemble monopolar or disorganized spindles. Chromosomes in Kif2b-deficient cells show typical kinetochore-microtubule attachments, but the velocity of movement is reduced ∼80% compared with control cells. Some Kif2b-deficient cells attempt anaphase, but the …

A Molecular Evaluation Of The North American “Grassland” Sparrow Clade, John Klicka, Garth M. Spellman

Ornithology Program (HRC)

Because they share several morphological and ecological characters, the North American sparrow (Emberizidae) genera Ammodramus, Passerculus, and Xenospiza have historically been considered members of a well-defined “grassland” sparrow assemblage. Relationships among the 11 members of this group have been the subject of much taxonomic debate, yet no comprehensive molecular assessment of relationships has been done. We investigated these relationships using mitochondrial DNA sequence data that included complete cytochrome-b and ND2 genes. Phylogenetic reconstructions derived via parsimony, likelihood, and Bayesian methods were congruent. The grassland sparrows, as presently configured, are polyphyletic. Pooecetes gramineus, Amphispiza belli (but not A. …

Genome Size Evolution In Relation To Leaf Strategy And Metabolic Rates Revisited, Jeremy M. Beaulieu, Ilia J. Leitch, Charles A. Knight

Biological Sciences

• Background and AimsIt has been proposed that having too much DNA may carry physiological consequences for plants. The strong correlation between DNA content, cell size and cell division rate could lead to predictable morphological variation in plants, including a negative relationship with leaf mass per unit area (LMA). In addition, the possible increased demand for resources in species with high DNA content may have downstream effects on maximal metabolic efficiency, including decreased metabolic rates.

• MethodsTests were made for genome size-dependent variation in LMA and metabolic rates (mass-based photosynthetic rate and dark respiration rate) using our own …

Modeling And Partitioning The Nucleotide Evolutionary Process For Phylogenetic And Comparative Genomic Inference, Todd Castoe

Electronic Theses and Dissertations

The transformation of genomic data into functionally relevant information about the composition of biological systems hinges critically on the field of computational genome biology, at the core of which lies comparative genomics. The aim of comparative genomics is to extract meaningful functional information from the differences and similarities observed across genomes of different organisms. We develop and test a novel framework for applying complex models of nucleotide evolution to solve phylogenetic and comparative genomic problems, and demonstrate that these techniques are crucial for accurate comparative evolutionary inferences. Additionally, we conduct an exploratory study using vertebrate mitochondrial genomes as a model …

The Cynipoid Genus Paramblynotus: Revision, Phylogeny, And Historical Biogeography (Hymenoptera, Liopteridae), Zhiwei Liu, Fredrik Ronquist, Goeran Nordlander

Zhiwei Liu

The genus Paramblynotus is the most species-rich genus of the so-called macrocynipoids, the large cynipoid parasitoids of wood-boring and cone-boring insect larvae. The species range in size from some of the largest to the smallest macrocynipoids, comparable in size to microcynipoids. Paramblynotus members occur on all continents except Europe and Australia, with most species being tropical or subtropical. The biology is poorly known but a few observations indicate that the species are parasitoids of beetle larvae. In this monographic revision of the genus, we present a species-level cladistic analysis based on qualitative and quantitative features of the external morphology. For …

Comparative Analysis Of Virulence Genes, Genetic Diversity, And Phylogeny Of Commensal And Enterotoxigenic Escherichia Coli Isolates From Weaned Pigs, Xi-Yang Wu, Toni A. Chapman, Darren J. Trott, Karl A Bettelheim, Thuy N. Do, Steve Driesen, Mark J. Walker, James Chin

Faculty of Science - Papers (Archive)

If the acquisition of virulence genes (VGs) for pathogenicity were not solely acquired through horizontal gene transfers of pathogenicity islands, transposons, and phages, then clonal clusters of enterotoxigenic Escherichia coli (ETEC) would contain few or even none of the VGs found in strains responsible for extraintestinal infections. To evaluate this possibility, 47 postweaning diarrhea (PWD) ETEC strains from different geographical origins and 158 commensal E. coli isolates from the gastrointestinal tracts of eight group-housed healthy pigs were screened for 36 extraintestinal and 18 enteric VGs using multiplex PCR assays. Of 36 extraintestinal VGs, only 8 were detected (fimH, …

Systematics Of Iochrominae (Solanaceae): Patterns In Floral Diversity And Interspecific Crossability, Stacey Dewitt Smith, David A. Baum

School of Biological Sciences: Faculty Publications

Iochrominae is a florally diverse clade of 34 Andean species and six traditionally recognized genera within Physaleae. Recent phylogenetic estimates suggest that four of the six traditional genera of Iochrominae are not monophyletic. Using this phylogenetic framework, we examine the evolution of floral morphology and interspecific crossability in Iochrominae. Iochrominae is inferred to have had ancestrally a purple corolla, but now manifests a wide range of colors (red/orange, yellow, green, purple or white), several of which appear to have arisen multiple times. Other floral traits traditionally employed in taxonomy, including corolla shape, corolla length, and stapet form, are similarly evolutionarily …

The Cynipoid Genus Paramblynotus: Revision, Phylogeny, And Historical Biogeography (Hymenoptera, Liopteridae), Zhiwei Liu, Fredrik Ronquist, Goeran Nordlander

Faculty Research & Creative Activity

The genus Paramblynotus is the most species-rich genus of the so-called macrocynipoids, the large cynipoid parasitoids of wood-boring and cone-boring insect larvae. The species range in size from some of the largest to the smallest macrocynipoids, comparable in size to microcynipoids. Paramblynotus members occur on all continents except Europe and Australia, with most species being tropical or subtropical. The biology is poorly known but a few observations indicate that the species are parasitoids of beetle larvae. In this monographic revision of the genus, we present a species-level cladistic analysis based on qualitative and quantitative features of the external morphology. For …