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Full-Text Articles in Life Sciences

Are Microbes Fundamentally Different Than Macroorganisms? Convergence And A Possible Case For Neutral Phenotypic Evolution In Testate Amoeba (Amoebozoa: Arcellinida), Angela M. Oliverio, Daniel J.G. Lahr, Jessica Grant, Laura A. Katz Dec 2015

Are Microbes Fundamentally Different Than Macroorganisms? Convergence And A Possible Case For Neutral Phenotypic Evolution In Testate Amoeba (Amoebozoa: Arcellinida), Angela M. Oliverio, Daniel J.G. Lahr, Jessica Grant, Laura A. Katz

Biological Sciences: Faculty Publications

This study reveals extensive phenotypic convergence based on the non-monophyly of genera and morphospecies of testate (shelled) amoebae. Using two independent markers, small subunit ribosomal DNA (ssu-rDNA) and mitochondrial cytochrome oxidase I (COI), we demonstrate discordance between morphology and molecules for ‘core Nebela’ species (Arcellinida; Amoebozoa). Prior work using just a single locus, ssu-rDNA, also supported the non-monophyly of the genera Hyalosphenia and Nebela as well as for several morphospecies within these genera. Here, we obtained COI gene sequences of 59 specimens from seven morphospecies and ssu-rDNA gene sequences of 50 specimens from six morphospecies of hyalosphenids. Our analyses …


An Epigenetic Toolkit Allows For Diverse Genome Architectures In Eukaryotes, Xyrus X. Maurer-Alcalá, Laura A. Katz Dec 2015

An Epigenetic Toolkit Allows For Diverse Genome Architectures In Eukaryotes, Xyrus X. Maurer-Alcalá, Laura A. Katz

Biological Sciences: Faculty Publications

Genome architecture varies considerably among eukaryotes in terms of both size and structure (e.g. distribution of sequences within the genome, elimination of DNA during formation of somatic nuclei). The diversity in eukaryotic genome architectures and the dynamic processes are only possible due to the well-developed epigenetic toolkit, which probably existed in the Last Eukaryotic Common Ancestor (LECA). This toolkit may have arisen as a means of navigating the genomic conflict that arose from the expansion of transposable elements within the ancestral eukaryotic genome. This toolkit has been coopted to support the dynamic nature of genomes in lineages across the eukaryotic …


Synthesis Of Phylogeny And Taxonomy Into A Comprehensive Tree Of Life, Cody E. Hinchliff, Stephen A. Smith, James F. Allman, J. Gordon Burleigh, Ruchi Chaudhary, Lyndon M. Coghill, Keith A. Crandall, Jiabin Deng, Bryan T. Drew, Romina Gazis, Karl Gude, David S. Hibbett, Laura A. Katz, H. Dail Laughinghouse Iv, Emily Jane Mctavish, Peter E. Midford, Christopher L. Owen, Richard H. Ree, Jonathan A. Rees, Douglas E. Soltis, Tiffani Williams, Karen A. Cranston Oct 2015

Synthesis Of Phylogeny And Taxonomy Into A Comprehensive Tree Of Life, Cody E. Hinchliff, Stephen A. Smith, James F. Allman, J. Gordon Burleigh, Ruchi Chaudhary, Lyndon M. Coghill, Keith A. Crandall, Jiabin Deng, Bryan T. Drew, Romina Gazis, Karl Gude, David S. Hibbett, Laura A. Katz, H. Dail Laughinghouse Iv, Emily Jane Mctavish, Peter E. Midford, Christopher L. Owen, Richard H. Ree, Jonathan A. Rees, Douglas E. Soltis, Tiffani Williams, Karen A. Cranston

Biological Sciences: Faculty Publications

Reconstructing the phylogenetic relationships that unite all line- ages (the tree of life) is a grand challenge. The paucity of homologous character data across disparately related lineages currently renders direct phylogenetic inference untenable. To reconstruct a comprehensive tree of life, we therefore synthesized published phylogenies, together with taxonomic classifications for taxa never incorporated into a phylogeny. We present a draft tree containing 2.3 million tips— the Open Tree of Life. Realization of this tree required the assembly of two additional community resources: (i) a comprehensive global reference taxonomy and (ii) a database of published phylogenetic trees mapped to this taxonomy. …


Recent Events Dominate Interdomain Lateral Gene Transfers Between Prokaryotes And Eukaryotes And, With The Exception Of Endosymbiotic Gene Transfers, Few Ancient Transfer Events Persist, Laura A. Katz Aug 2015

Recent Events Dominate Interdomain Lateral Gene Transfers Between Prokaryotes And Eukaryotes And, With The Exception Of Endosymbiotic Gene Transfers, Few Ancient Transfer Events Persist, Laura A. Katz

Biological Sciences: Faculty Publications

While there is compelling evidence for the impact of endosymbiotic gene transfer (EGT; transfer from either mitochondrion or chloroplast to the nucleus) on genome evolution in eukaryotes, the role of interdomain transfer from bacteria and/or archaea (i.e. prokaryotes) is less clear. Lateral gene transfers (LGTs) have been argued to be potential sources of phylogenetic information, particularly for reconstructing deep nodes that are difficult to recover with traditional phylogenetic methods. We sought to identify interdomain LGTs by using a phylogenomic pipeline that generated 13 465 single gene trees and included up to 487 eukaryotes, 303 bacteria and 118 archaea. Our goals …


Gene Expression Associated With White Syndromes In A Reef Building Coral, Acropora Hyacinthus, Rachel M. Wright, Galina V. Aglyamova, Eli Meyer, Mikhail V. Matz May 2015

Gene Expression Associated With White Syndromes In A Reef Building Coral, Acropora Hyacinthus, Rachel M. Wright, Galina V. Aglyamova, Eli Meyer, Mikhail V. Matz

Biological Sciences: Faculty Publications

Background: Corals are capable of launching diverse immune defenses at the site of direct contact with pathogens, but the molecular mechanisms of this activity and the colony-wide effects of such stressors remain poorly understood. Here we compared gene expression profiles in eight healthy Acropora hyacinthus colonies against eight colonies exhibiting tissue loss commonly associated with white syndromes, all collected from a natural reef environment near Palau. Two types of tissues were sampled from diseased corals: visibly affected and apparently healthy. Results: Tag-based RNA-Seq followed by weighted gene co-expression network analysis identified groups of co-regulated differentially expressed genes between all health …


Analyses Of Alternatively Processed Genes In Ciliates Provide Insights Into The Origins Of Scrambled Genomes And May Provide A Mechanism For Speciation, Feng Gao, Scott W. Roy, Laura A. Katz Feb 2015

Analyses Of Alternatively Processed Genes In Ciliates Provide Insights Into The Origins Of Scrambled Genomes And May Provide A Mechanism For Speciation, Feng Gao, Scott W. Roy, Laura A. Katz

Biological Sciences: Faculty Publications

Chromosome rearrangements occur in a variety of eukaryotic life cycles, including during the development of the somatic macronuclear genome in ciliates. Previous work on the phyllopharyngean ciliate Chilodonella uncinata revealed that macronuclear β-tubulin and protein kinase gene families share alternatively processed germ line segments nested within divergent regions. To study genome evolution in this ciliate further, we characterized two additional alternatively processed gene families from two cryptic species of the ciliate morphospecies C. uncinata: those encoding histidine acid phosphatase protein (Hap) and leishmanolysin family protein (Lei). Analyses of the macronuclear Hap and Lei sequences reveal that each gene family consists …


Sapocribrum Chincoteaguense N. Gen. N. Sp.: A Small, Scale-Bearing Amoebozoan With Flabellinid Affinities, Daniel J.G. Lahr, Jessica Grant, Robert Molestina, Laura A. Katz, O. Roger Anderson Jan 2015

Sapocribrum Chincoteaguense N. Gen. N. Sp.: A Small, Scale-Bearing Amoebozoan With Flabellinid Affinities, Daniel J.G. Lahr, Jessica Grant, Robert Molestina, Laura A. Katz, O. Roger Anderson

Biological Sciences: Faculty Publications

The isolate American Type Culture Collection (ATCC)® 50979 is a small amoebozoan whose actin gene was previously characterized, but did not allow a stable phylogenetic placement. This isolate was originally mis-identified upon deposition, and subsequently mis-illustrated in a recent publication. Here, we provide both a detailed morphological description as well as additional molecular analyses in order to clarify the isolate's phylogenetic relationships. The amoeba is minute (less than 5 μm), and presents the behavior of staying in a fixed location, while emitting one or two thin pseudopods. Transmission electron microscopy reveals that the cell is covered in a …