Genomics Commons^™

Micrornas And The Advent Of Vertebrate Morphological Complexity, Alysha M. Heimberg, Lorenzo F. Sempere, Vanessa N. Moy, Phillip C. J. Donoghue, Kevin J. Peterson

Dartmouth Scholarship

The causal basis of vertebrate complexity has been sought in genome duplication events (GDEs) that occurred during the emergence of vertebrates, but evidence beyond coincidence is wanting. MicroRNAs (miRNAs) have recently been identified as a viable causal factor in increasing organismal complexity through the action of these ≈22-nt noncoding RNAs in regulating gene expression. Because miRNAs are continuously being added to animalian genomes, and, once integrated into a gene regulatory network, are strongly conserved in primary sequence and rarely secondarily lost, their evolutionary history can be accurately reconstructed. Here, using a combination of Northern analyses and genomic searches, we show …

Effect Of Thyroid Hormone Concentration On The Transcriptional Response Underlying Induced Metamorphosis In The Mexican Axolotl (Ambystoma), Robert B. Page, Stephen R. Voss, Amy K. Samuels, Jeramiah J. Smith, Srikrishna Putta, Christopher K. Beachy

Biology Faculty Publications

BACKGROUND: Thyroid hormones (TH) induce gene expression programs that orchestrate amphibian metamorphosis. In contrast to anurans, many salamanders do not undergo metamorphosis in nature. However, they can be induced to undergo metamorphosis via exposure to thyroxine (T4). We induced metamorphosis in juvenile Mexican axolotls (Ambystoma mexicanum) using 5 and 50 nM T4, collected epidermal tissue from the head at four time points (Days 0, 2, 12, 28), and used microarray analysis to quantify mRNA abundances.

RESULTS: Individuals reared in the higher T4 concentration initiated morphological and transcriptional changes earlier and completed metamorphosis by Day 28. In contrast, initiation of metamorphosis …

High-Throughput Genotyping With The Goldengate Assay In The Complex Genome Of Soybean, David L. Hyten, Qijian Song, Ik-Young Choi, Mun-Sup Yoon, James E. Specht, Lakshimi Matukumalli, Randall L. Nelson, Randy C. Shoemaker, Nevin D. Young, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Large numbers of single nucleotide polymorphism (SNP) markers are now available for a number of crop species. However, the high-throughput methods for multiplexing SNP assays are untested in complex genomes, such as soybean, that have a high proportion of paralogous genes. The Illumina GoldenGate assay is capable of multiplexing from 96 to 1,536 SNPs in a single reaction over a 3-day period. We tested the GoldenGate assay in soybean to determine the success rate of converting verified SNPs into working assays. A custom 384-SNP GoldenGate assay was designed using SNPs that had been discovered through the resequencing of five diverse …

High Rate Of Recent Transposable Element–Induced Adaptation In Drosophila Melanogaster, Josefa Gonzalez, Kapa Lenkov, Mikhail Lipatov, J. Michael Macpherson, Dmitri A. Petrov

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Although transposable elements (TEs) are known to be potent sources of mutation, their contribution to the generation of recent adaptive changes has never been systematically assessed. In this work, we conduct a genome-wide screen for adaptive TE insertions in Drosophila melanogaster that have taken place during or after the spread of this species out of Africa. We determine population frequencies of 902 of the 1,572 TEs in Release 3 of the D. melanogaster genome and identify a set of 13 putatively adaptive TEs. These 13 TEs increased in population frequency sharply after the spread out of Africa. We argue that …

Transcriptional Profiling Of Aphid Resistant And Susceptible Melon (Cucumis Melo) Following Cotton -Melon Aphid (Aphis Gossypii) Feeding, Preethi Samuel

Theses and Dissertations

The interaction between phloem feeding aphids Aphis gossypii (cotton-melon aphid) and Cucumis melo (melon) provides an opportunity to elucidate the means by which a host plant defends itself against aphid attack. The relationship is of scientific as well as economic importance since A. gossypii is among the most destructive insects to agriculture in the U.S. and abroad. The resistance to A. gossypii in melon is controlled at the Vat (Virus aphid transmission) locus by a major dominant gene, Vat that has the unique feature of conferring resistance to A. gossypii and resistance to transmission of non-persistent viruses by A. gossypii …

United States Regulation Of Stem Cell Research: Recasting Government's Role And Questions To Be Resolved, Owen C. B. Hughes, Alan L. Jakimo, Michael J. Malinowski

Journal Articles

This article directly addresses the stem cell controversy, but also the broader history and norms regarding the roles of federal and state government in U.S. science research funding.

Ecological Genomics: Understanding Gene And Genome Function In The Natural Environment, M. C. Ungerer, L. C. Johnson, M. A. Herman

School of Biological Sciences: Faculty Publications

The field of ecological genomics seeks to understand the genetic mechanisms underlying responses of organisms to their natural environments. This is being achieved through the application of functional genomic approaches to identify and characterize genes with ecological and evolutionary relevance. By its very nature, ecological genomics is an interdisciplinary field. In this review, we consider the significance of this new area of study from both an ecological and genomic perspective using examples from the recent literature. We submit that by considering more fully an ecological context, researchers may gain additional insights into the underlying genetic basis of ecologically relevant phenotypic …