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Full-Text Articles in Biology
An Inducible Predator Defense In The Marine Microalga Emiliania Huxleyi (Prymnesiophyceae) Is Linked To Its Heteromorphic Haploid-Diploid Life Cycle, Amelia Kolb
WWU Graduate School Collection
Marine phytoplankton are important players in the global ecosystem, contributing up to 50% of global primary productivity. Predation by microzooplankton is one of the most important sources of mortality for phytoplankton. However, phytoplankton defenses against predators are not well understood despite their expected importance. I tested for inducible defenses in the coccolithophore Emiliania huxleyi, an abundant and ecologically important bloom-forming species with a heteromorphic haploid-diploid life cycle, against the common ciliate predator, Strombidinopsis acuminatum. The calcifying diploid and non-calcifying, flagellated haploid phases of E. huxleyi likely occupy different ecological niches, potentially explaining the maintenance of haploid-diploidy in this species. The …
Characterization Of Phprp1, An Extracellular Arabinogalactan Protein From Petunia Hybrida Pistils, Megan Twomey
Characterization Of Phprp1, An Extracellular Arabinogalactan Protein From Petunia Hybrida Pistils, Megan Twomey
WWU Graduate School Collection
An extracellular arabinogalactan protein, PhPRP1, was identified from Petunia hybrida pistils on the basis of nucleotide sequence similarity with NaTTS from Nicotiana alata and TTS-1 from Nicotiana tabacum. PhPRP1 exhibits 83% and 81% nucleotide identity with NaTTS and TTS-1 cDNAs, respectively. The amino acid sequence deduced from the cDNA predicts a 27.4 kDa polypeptide backbone with a 25 amino acid signal sequence. Sequence alignments of PhPRP1 and the TTS proteins reveals two hypervariable regions, including a proline-rich domain with noncontiguous KPP repeats. A short, highly-conserved histidinerich domain separates the two hypervariable regions. The C-terminal segment of the protein shows significant …
Promoter Deletion Analysis And Identification Of Putative Cis-Elements Of Mute In Arabidopsis, Aaron Mahoney
Promoter Deletion Analysis And Identification Of Putative Cis-Elements Of Mute In Arabidopsis, Aaron Mahoney
WWU Graduate School Collection
Stomata are found on the surfaces of land plants and are crucial for regulating gas exchange between plants and the atmosphere. These structures are composed of a pore that is surrounded by two specialized guard cells. The critical importance of stomata in providing CO2 uptake while controlling the release of water has made them a prime target for improvement of plant productivity and water use efficiency. In Arabidopsis, the production of a mature stomata requires the expression of the basic helix-loop-helix (bHLH) master regulatory gene, MUTE. The function of MUTE and its expression pattern have been characterized. In this study, …
Land Use, Riparian Buffers, And Biological Stream Conditions In The Puget Lowlands Of Washington, Colin Wahl
Land Use, Riparian Buffers, And Biological Stream Conditions In The Puget Lowlands Of Washington, Colin Wahl
WWU Graduate School Collection
Stream conservation and restoration strategies often focus on preserving extant riparian forest and restoring riparian habitat. In the Pacific Northwest, these efforts are often directed toward restoring and maintaining habitat that supports salmon populations. Riparian restoration, though beneficial to stream habitat, may not be sufficient to restore functioning stream ecosystems in watersheds heavily altered by intensive land use. To evaluate this hypothesis, I measured the biological condition of streams affected by human activity, and compared reaches with and without limited riparian corridors. I assessed 12 streams in watersheds dominated by different land use (cultivated, developed, forested, grassland) and sampled from …
Potential Effects Of Short-Term Climate Variation On Shrubs, Grasshoppers And Lizards In The Northern Great Basin Desert Scrub, Philip J. Dugger
Potential Effects Of Short-Term Climate Variation On Shrubs, Grasshoppers And Lizards In The Northern Great Basin Desert Scrub, Philip J. Dugger
WWU Graduate School Collection
Analyzing trophic interactions among organisms may refine our ability to predict the impacts of climate change on organismal communities in an ecosystem or biome. The Great Basin desert scrub biome comprises relatively simple biotic communities in which bottom-up trophic processes should be comparatively easy to document, analyze and understand. Observing 1) the direct effects of abiotic factors (precipitation and temperature) on desert primary producers, primary consumers, and secondary consumers and 2) the indirect effects of abiotic factors on desert community members--as mediated by biotic effects--should enhance our understanding of community trophic dynamics and may improve the accuracy of biotic predictions …
Tts Protein Orthologs As Interspecific Reproductive Barriers In The Solanaceae, Tara D. Callaway
Tts Protein Orthologs As Interspecific Reproductive Barriers In The Solanaceae, Tara D. Callaway
WWU Graduate School Collection
TTS (transmitting tissue-specific) proteins are abundant in the extracellular matrix (ECM) of the transmitting tissue, which forms the pollen tube pathway in Nicotiana pistils. These arabinogalactan proteins stimulate pollen tube growth and are vital for optimal seed set. I have cloned and sequenced two putative orthologs, PiPRP1 and PaPRP1, which are expressed in the pistils of Petunia integrifolia and Petunia axillaris, respectively. Comparison of the domain architecture and cross-reactivity with anti-TTS protein antibodies confirm that the proteins encoded by these Petunia cDNA clones are orthologs of TTS proteins (TTSPs) from Nicotiana species. Using immunological detection methods, I have shown that …
The Effects Of Elevated Pco2 On The Physiology Of Emiliania Huxleyi, Tristen Wuori
The Effects Of Elevated Pco2 On The Physiology Of Emiliania Huxleyi, Tristen Wuori
WWU Graduate School Collection
This study examined the effects of elevated CO2 on the microalga Emiliania huxleyi. Two strains were compared, a calcifying (CCMP 2668) and a non-calcifying (CCMP 374) strain. The CO2 levels used were 390 ppm, 760 ppm, and 1000 ppm. The effects of CO2 on growth rate, cell size, calcification, particulate dimethylsulfoniopropionate (DMSPp), and chlorophyll were examined. Under elevated CO2, cell size in both strains and DMSPp in the calcifying strain increased. Calcification decreased under elevated CO2. DMSPp in the non-calcifying strain and chlorophyll content in the calcifying strain had non-linear responses when exposed to elevated CO2. Growth rate in both …
Rnai Suppressor Screen To Identify Novel Genetic Interactors With The Sydn-1/Pfs-2 Neurodevelopmental Pathway Of Caenorhabditis Elegans And Construction Of Plasmid Vectors For Yeast-Two-Hybrid And In Vivo Analyses, Mitchell Lee
WWU Graduate School Collection
Proper development of neuronal circuits are crucial for nervous system functioning. A novel pathway regulating axon and synapse development in Caenorhabditis elegans through nuclear 3'-end polyadenylation of nascent mRNA has recently been uncovered (Van Epps et al., 2010). In this pathway, the protein product of the gene synaptic defective enhancer (sydn-1) negatively regulates polyadenylation factor subunit homolog (PFS-2), an evolutionarily conserved scaffolding protein in a multi-protein complex involved in mRNA 3' -end processing. Although 3'-end processing of mRNA has a regulatory role in many cellular processes, regulation of synapse and axon development via this cellular mechanism has not been characterized. …