APEX Presentations
October 25 , 2007
Expression Patterns of Pathogen-Related Genes in edr1 and suppressor 69 Mutants of Arabidopsis thaliana
Name: Rebecca Roemer
Major: Biochemistry
Academic Advisors: Brad Goodner and Prudy Hall
APEX Advisor: Prudy Hall
Location: Indiana University
Dr. Roger Innes
Myer 319b, Indiana University
812.855.2219
Funding: National Science Foundation
This project aimed to determine which genes are being regulated at the level of transcription when Arabidopsis thaliana is infected with a pathogen. The edr1 mutant was previously discovered to have enhanced resistance to Erysiphe cichoracearus, which causes powdery mildew in many crops. Expression of pathogen-related genes was determined utilizing quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Previous microarray data identified 7 genes differentially expressed before and after inoculation of E. cichoracearum in edr1 mutant plants. The edr1 mutant is hypersensitive to ABA (abscisic acid) treatment, however the effect of the edr1 mutation on ABA signaling is unknown. The KEG gene is needed for ABA signaling; suppressor 69 suppresses the edr1 mutation through a mutation in the KEG gene. To determine explicitly which pathogen-related genes are affected by KEG and EDR1, transgenic lines that overexpress the KEG and EDR1 genes were analyzed. This data helped determine which of the original genes are of interest. Two genes, At4g17500 and A5g57560, are noticeably affected by the edr1 mutation 30 hr after inoculation. The seedlings induced with ABA for 2 hr indicated that the edr1 mutation also affects ABA-induced genes.
Boundaries of Gecko Adhesion: Surfaces and Temperartures
Name: Emily Hagan
Majors: Biology & Biomedical Humanities
Academic and APEX Advisor: Matthew Hils
Location: University of Akron, Polymer Department
Dr. Ali Dhinojwala (with additional input from: Dr. Peter H. Niewiarowski, Liehui Ge, and Stephanie Lopez)
The University of Akron Department of Polymer Science
170 University Circle
Goodyear Polymer Center
Akron, Ohio 44325-3909
330.972.6246
Funding: National Science Foundation (NSF REU Polymer Science, DMR 0648318)
The ability of geckos to adhere to surfaces of varied texture in both a vertical and inverted orientation has intrigued scientists for centuries. The hierarchy of the toe pad structure has been thoroughly examined and the nano- hair-like structures (setae), and their division into spatulae allow for intimate contact with a surface. Previous data show that the adhesion is due to van der Waals intermolecular forces and thus should be independent of temperature. However, there may be an intrinsic relationship between the skeletomuscular system of the gecko, which gives the setae proper orientation and preload force, and the organism’s adhesion. A comparison of adhesion strength between two commonly studied species, Gekko gecko and Phelsuma dubia, was tested to examine the effects of temperature (12-32º C) and substrates (vertical glass and horizontal Teflon). The trials revealed that both species had greater adhesion values at 12ºC on vertical glass, and were successfully able to adhere to horizontal Teflon, though with low adhesive strength. Studying the biological aspect of this novel adhesion is essential to be able to successfully replicate this phenomenon synthetically for a range of possible applications. Current synthetic attempts to reproduce the hair-like structures of the gecko were done using multiwalled carbon nanotubes.
Endangered Ugly Things
Name: Nathan Yaussy
Major: Biology
Academic and APEX Advisor: Denny Taylor
Location: Cuyahoga Valley National Park
Meg Plona
Biologist, Cuyahoga Valley National Park
15610 Vaughn Road, Brecksville, OH 44141
330.342.0764 Ex. 2
Media coverage of ecological issues focuses attention on global problems that often are disconnected from local ecology. Nature education programs increasingly take children out of nature and into an electronic environment centered on larger issues. This presentation highlights part of the new trend in science education that ties on-line education to local environments in the backyards of students. I report here the creation of Endangered Ugly Things, a weblog where I highlight endangered animals that would otherwise go unnoticed. Recently the blog has focused attention on Ohio's freshwater environments based on my summer internship working on Primary Headwater Habitat Analysis in the Cuyahoga Valley National Park, with the hopes that children will become interested in exploring those habitats and learning about Ohio's lead in biomonitoring of rivers, streams and wetland habitats.