Digital Commons Network^™

Conservation And Loss Of Ribosomal Rna Gene Sites In Diploid And Polyploid Fragaria (Rosaceae), Bo Liu, Thomas M. Davis

Biological Sciences

The genus Fragaria comprises species at ploidy levels ranging from diploid (2n = 2x = 14) to decaploid (2n = 10x = 70). Fluorescence in situ hybridization with 5S and 25S rDNA probes was performed to gather cytogenetic information that illuminates genomic divergence among different taxa at multiple ploidy levels, as well as to explore the evolution of ribosomal RNA genes during polyploidization in Fragaria.

A Strawberry Knox Gene Regulates Leaf, Flower And Meristem Architecture, Mithu Chatterjee, Claudia L. Bermudez-Lozano, Maureen A. Clancy, Thomas M. Davis, Kevin M. Folta

Biological Sciences

The KNOTTED-LIKE HOMEODOMAIN (KNOX) genes play a central role in maintenance of the shoot apical meristem. They also contribute to the morphology of simple and compound leaves. In this report we characterize the FaKNOX1 gene from strawberry (Fragaria spp.) and demonstrate its function in trasgenic plants. The FaKNOX1 cDNA was isolated from a cultivated strawberry (F.×ananassa) flower EST library. The sequence is most similar to Class I KNOX genes, and was mapped to linkage group VI of the diploid strawberry genome. Unlike most KNOX genes studied, steady-state transcript levels were highest in flowers and fruits. Transcripts were also detected in …

An Examination Of Targeted Gene Neighborhoods In Strawberry, Thomas M. Davis, Melanie E. Shields, Qian Zhang, Denise Tombolato-Terzić, Jeffrey L. Bennetzen, Ana C. Pontaroli, Hao Wang, Qin Yao, Phillip Sanmiguel, Kevin M. Folta

Biological Sciences

This report details the structure and content of targeted regions of the strawberry genome. The data indicate that the strawberry genome is gene-dense, with an average of one protein-encoding gene or pseudogene per 5.9 kb. Current overall EST coverage is sparse. The unexpected gene duplications and their differential patterns of EST support suggest possible subfunctionalization or pseudogenization of these sequences. This report provides a high-resolution depiction of targeted gene neighborhoods that will aid whole-genome sequence assembly, provide valuable tools for plant breeders and advance the understanding of strawberry genome evolution.

An Enhanced Method For Sequence Walking And Paralog Mining: Topo® Vector-Ligation Pcr, Benjamin B. Orcheski, Thomas M. Davis

Biological Sciences

Background

Although technological advances allow for the economical acquisition of whole genome sequences, many organisms' genomes remain unsequenced, and fully sequenced genomes may contain gaps. Researchers reliant upon partial genomic or heterologous sequence information require methods for obtaining unknown sequences from loci of interest. Various PCR based techniques are available for sequence walking - i.e., the acquisition of unknown DNA sequence adjacent to known sequence. Many such methods require rigid, elaborate protocols and/or impose narrowly confined options in the choice of restriction enzymes for necessary genomic digests. We describe a new method, TOPO^® Vector-Ligation PCR (or TVL-PCR) that innovatively …