Digital Commons Network^™

The Rice Miniature Inverted Repeat Transposable Element Mping Is An Effective Insertional Mutagen In Soybean, C. Nathan Hancock, Feng Zhang, Kristen Floyd, Aaron O. Richardson, Peter Lafayette, Donna Tucker, Susan R. Wessler, Wayne A. Parrott

Faculty Publications

Insertional mutagenesis of legume genomes such as soybean (Glycine max) should aid in identifying genes responsible for key traits such as nitrogen fixation and seed quality. The relatively low throughput of soybean transformation necessitates the use of a transposon-tagging strategy where a single transformation event will produce many mutations over a number of generations. However, existing transposon-tagging tools being used in legumes are of limited utility because of restricted transposition (Ac/Ds: soybean) or the requirement for tissue culture activation (Tnt1: Medicago truncatula). A recently discovered transposable element from rice (Oryza …

Aintegumenta And Aintegumenta-Like6 Regulate Auxin-Mediated Flower Development In Arabidopsis, Beth A. Krizek

Faculty Publications

Background: Two related genes encoding AP2/ERF-type transcription factors, AINTEGUMENTA (ANT) and AINTEGUMENTA-LIKE6 (AIL6), are important regulators of floral growth and patterning in Arabidopsis. Evidence suggests that these genes promote several aspects of flower development in response to auxin. To investigate the interplay of ANT, AIL6 and auxin during floral development, I have examined the phenotypic consequences of disrupting polar auxin transport in ant, ail6 and ant ail6 mutants by either genetic or chemical means.

Results: Plants containing mutations in ANT or AIL6 alone or in both genes together exhibit increased sensitivity to disruptions in polar auxin transport. …

Homoplastic Microinversions And The Avian Tree Of Life, E. L. Braun, R T. Kimball, K. L. Han, N. R. Luhasz-Velez, A. J. Bonilla, Jena L. Chojnowski, J. V. Smith, R. C. Bowie, M. J. Braun, S. J. Hackett, J. Harshman, C. J. Huddleston, B. D. Marks, W. S. Moore, S. Reddy, F. H. Sheldon, C. C. Witt, T. Yuri

Faculty Publications

BACKGROUND:

Microinversions are cytologically undetectable inversions of DNA sequences that accumulate slowly in genomes. Like many other rare genomic changes (RGCs), microinversions are thought to be virtually homoplasy-free evolutionary characters, suggesting that they may be very useful for difficult phylogenetic problems such as the avian tree of life. However, few detailed surveys of these genomic rearrangements have been conducted, making it difficult to assess this hypothesis or understand the impact of microinversions upon genome evolution.

RESULTS:

We surveyed non-coding sequence data from a recent avian phylogenetic study and found substantially more microinversions than expected based upon prior information about vertebrate …

Electrospinning Fabrication, Structural And Mechanical Characterization Of Rod-Like Virus-Based Composite Nanofibers, Laying Wu, Jianfeng Zang, L. Andrew Lee, Zhongwei Niu, Gary C. Horvatha, Vaughn Braxtona, Arief C. Wibowo, Michael A. Bruckman, Soumitra Ghoshroy, Hans-Conrad Zur Loye, Xiaodong Li, Qian Wang

Faculty Publications

Tobacco mosaic virus (TMV) was electrospun with polyvinyl alcohol (PVA) into continuous TMV–PVA composite nanofibers to form a biodegradable nonwoven fibrous mat as an extracellular matrix (ECM) mimetic. Morphological characterizations by electron microscopyshowed that the addition of varying amounts of TMV resulted in homogeneous nanofibers without phase separation and did not change the diameter of the composite nanofibers. The orientation of TMV in as-spun fibers could be readily controlled and post-processing of the nonwoven TMV–PVA mat significantly improved its water resistance. In addition, tensile tests were performed on individual nanofibers, which revealed that the TMV–PVA composite nanofibers achieved a comparable …

Across Bacterial Phyla, Distantly-Related Genomes With Similar Genomic Gc Content Have Similar Patterns Of Amino Acid Usage, John Lightfield, Noah R. Fram, Bert Ely

Faculty Publications

The GC content of bacterial genomes ranges from 16% to 75% and wide ranges of genomic GC content are observed within many bacterial phyla, including both Gram negative and Gram positive phyla. Thus, divergent genomic GC content has evolved repeatedly in widely separated bacterial taxa. Since genomic GC content influences codon usage, we examined codon usage patterns and predicted protein amino acid content as a function of genomic GC content within eight different phyla or classes of bacteria. We found that similar patterns of codon usage and protein amino acid content have evolved independently in all eight groups of bacteria. …

Loose Ligands And Available Iron In The Ocean, Ronald Benner

Faculty Publications

No abstract provided.

Auxin Regulation Of Arabidopsis Flower Development Involves Members Of The Aintegumenta-Like/Plethora (Ail/Plt) Family, Beth A. Krizek

Faculty Publications

Auxin is an important regulator of many aspects of plant growth and development. During reproductive development, auxin specifies the site of flower initiation and subsequently regulates organ growth and patterning as well as later events that determine reproductive success. Underlying auxin action in plant tissues is its uneven distribution, resulting in groups of cells with high auxin levels (auxin maxima) or graded distributions of the hormone (auxin gradients). Dynamic auxin distribution within the periphery of the inflorescence meristems specifies the site of floral meristem initiation, while auxin maxima present at the tips of developing floral organ primordia probably mediate organ …

Hemebind: A Novel Method For Heme Binding Residue Prediction By Combining Structural And Sequence Information, R. Liu, Jianjun Hu

Faculty Publications

Background

Accurate prediction of binding residues involved in the interactions between proteins and small ligands is one of the major challenges in structural bioinformatics. Heme is an essential and commonly used ligand that plays critical roles in electron transfer, catalysis, signal transduction and gene expression. Although much effort has been devoted to the development of various generic algorithms for ligand binding site prediction over the last decade, no algorithm has been specifically designed to complement experimental techniques for identification of heme binding residues. Consequently, an urgent need is to develop a computational method for recognizing these important residues.

Results

Here …

Computational Prediction Of Heme-Binding Residues By Exploiting Residue Interaction Network, R. Liu, Jianjun Hu

Faculty Publications

Computational identification of heme-binding residues is beneficial for predicting and designing novel heme proteins. Here we proposed a novel method for heme-binding residue prediction by exploiting topological properties of these residues in the residue interaction networks derived from three-dimensional structures. Comprehensive analysis showed that key residues located in heme-binding regions are generally associated with the nodes with higher degree, closeness and betweenness, but lower clustering coefficient in the network. HemeNet, a support vector machine (SVM) based predictor, was developed to identify heme-binding residues by combining topological features with existing sequence and structural features. The results showed that incorporation of network-based …

Prediction Of Discontinuous B-Cell Epitopes Using Logistic Regression And Structural Information, R. Liu, Jianjun Hu

Faculty Publications

Computational prediction of discontinuous B-cell epitopes remains challenging, but it is an important task in vaccine design. In this study, we developed a novel computational method to predict discontinuous epitope residues by combining the logistic regression model with two important structural features, B-factor and relative accessible surface area (RASA). We conducted five-fold cross-validation on a representative dataset composed of antigen structures bound with antibodies and independent testing on Epitome database, respectively. Experimental results indicate that besides the well-known RASA feature, B-factor can also be used to identify discontinuous epitopes. Furthermore, these two features are complementary and their combination can remarkably …