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Undergraduate Research and Teaching Scholars Program 2006-2007
Ms. Ni Feng Ms. Emily Foote Ms. Anita Grover Mr. Anuj Khattar Mr. Sean Tsao Ms. Bella Zaghi
Ms. Ni Feng
Mentor: Dr. Barney Schlinger
Funding: Rose Hills Scholar
Title: A comparison of 5 alpha-, and 5 beta- reductase activities in the wing muscles of male and female Golden-collared Manakins (manacus vitellinus)
Ni Feng is a fourth year Biology major and Art History minor at UCLA. She is working under the mentorship of Dr. Barney Schlinger in the Physiological Sciences Department to investigate the role of sex steroid hormones on avian courtship behavior. In particular, she is interested in studying the Golden-collared Manakin (manacus vitellinus), a tropical bird found in the rainforests of Panama. To attract females, male Manakins perform a visually and acoustically stimulating courtship display that involves loud snapping sounds created by the forceful contraction of their wings. It has previously been shown that the neuromuscular system controlling this complex behavior is sexually dimorphic and sex steroid-sensitive. The Schlinger lab has also shown that in male Manakins, the three muscles controlling the wings, the scapulohumeralis caudalis, the supracoracoideus, and the pectoralis, exhibit morphological adaptations for rapid and forceful contractions. The motorneurons that innervate these muscles have shown to express androgen receptors, suggesting that the neuromuscular system controlling the display is androgen sensitive.
Thus, it is Ni’s interest to further investigate the role of testosterone (T) and its metabolites in stimulating the manakin display. For T to have its full effects on endocrine target tissues it is converted to one or more of its metabolites. In the androgen pathway, T is converted to 5 α- and/or 5 β-dihydrotestosterone (DHT) by the enzymes 5 α- and 5 β- reductase. For her project, Ni will be quantifying the activities of T-metabolizing enzymes 5 α- and 5 β- reductases in the above mentioned muscles of male and female manakins via biochemistry assays. She will also measure the activities of these enzymes in the zebra finch (Taenopygia guttata), a non-snapping bird, to look for differences across species as well as sex.
Ni would like to sincerely thank Dr. Schlinger for being such a great mentor and the Rose Hills Foundation for supporting her project. Ni also thoroughly enjoys tutoring AAP students and she would like to thank URC/CARE and Dr. Cramer for giving her this wonderful opportunity.
Ms. Emily Foote
Mentor: Dr. William Newman
Funding: Wasserman Scholar
Title: Cellular automata models for large earthquakes, forest fires, and models of conflict
Emily Foote is a senior in the Earth and Space science department and is in the College Honors Program. She tutors ESS 1 at the Academic Advancement Program (AAP) in Campbell Hall. After she receives her B.S. in Geology from UCLA this spring, she plans to continue her studies in Geology/Geophysics at a PhD granting institution. Emily is interested in studying the physics of earthquakes. Understanding earthquakes can lessen the catastrophic results of events such as the 2004 Sumatra Event and the 1906 San Francisco “big one.” Specifically, she is interested in looking at tectonic events that occur in California as a result of failures along the San Andreas Fault and modeling their statistical distribution by employing cellular automata models. She has been working with Dr. William I. Newman on this and related projects since the spring of 2005.
Professor Newman developed a new computational algorithm that makes it possible to perform large numbers of Monte Carlo simulations, often hundreds to thousands of times faster than previous researchers were able to perform them. Dr. Newman and Emily have written code both in FORTRAN and in C for this purpose. The output from these simulations will allow us to obtain more reliable statistics than can be obtained presently from the limited number of observed Southern California earthquakes and other model simulations. Technically, their model is associated with percolation theory in physics and has been adapted to the field of geophysics because it can simulate real large-scale events and the recurrence times between them. Percolation theory is a mathematical model that describes how patterns evolve in time and emerge over a region. Their model employs a square array of sites that randomly receive stress associated with tectonic activity. When 59.725% of the sites are stressed, a pattern emerges where the stressed region is contiguous and extends from one boundary of the system to another. This is called percolation. When applied to earthquakes, percolation corresponds to the rupture of a fault, which causes the earthquake. A cluster is a region with substantial stress. Professor Newman and Emily are also looking at cluster behavior and the change in cluster size over time. They increased the size of the two-dimensional lattice array to be able to capture more accurately the underlying statistics and its uncertainty.
Emily would like to thank Dr. Newman for allowing her to participate in this research project and for his continual support and encouragement for the last two years. She would also like to thank Mr. & Mrs. Lew Wasserman for their generous scholarship, Dr. Audrey Cramer and the Undergraduate Research Center for giving me this great opportunity.
Mr. Anita Grover
Mentor: Dr. Joseph DiStefano III
Funding: Wasserman Scholar
Title: Modeling Insulin Regulation of Glucose Transporter 4(picture pending)
Anita Grover is a senior Computational & Systems Biology major and Mathematics minor, graduating in Spring 2007. Her research interests lie primarily in mathematical modeling and simulation of human systems, particularly in areas relating to disease states. Anita has also been tutoring Chemistry 20A through the Academic Advancement Program since Fall 2005.
She began researching with Dr. Joseph DiStefano III through his Cybernetics 186L lab course in Spring 2006, and is continuing her project through graduation. In line with her interests, her current research involves modeling glucose transporter 4 (GLUT4), a receptor protein and glucose channel on the cell membrane of fat and muscle cells. Irregularities in this protein function have been implicated in type II, or late-onset, diabetes. When one of these cells senses insulin in the healthy patient, the concentration of GLUT4 at the cell membrane increases dramatically, thus increasing the amount of glucose in the cell. However, in diseased patients, the GLUT4 protein might display abnormal dynamic properties: for example, it might not arrive at the cell membrane from the inside of the cell quickly enough. Studying this receptor is a relatively new area of research pertaining to diabetes, as traditionally, only insulin sensitivity was studied. By understanding how this protein functions in the normal cell, irregularities in diseased patients will soon become much easier to detect.
Anita is currently applying to Ph.D. schools across the country to programs ranging from Pharmaceutical Sciences to Biomedical Engineering. She plans, upon finishing her Ph.D., to work in the pharmaceutical or biotech industry.
Mr. Anuj Khattar
Mentor: Dr. Steve Jacobsen and Dr. Lianna Johnson
Funding: Wasserman Scholar
Title: Characterization of Methyltransferase proteins containing SRA domains in Arabidopsis
(left to right) – Dr. Lianna Johnson, Anuj Khattar, and Dr.
Steve JacobsenAnuj Khattar is a 4th year Molecular, Cell, and Developmental Biology major and Public Health minor. He is involved in activities such as the UCLA Mobile Clinic, Healthcare Without Borders, UCLA Badminton Team, and he has worked as a LS4 (Introductory Genetics) tutor for the Academic Advancement Program since Fall 2005.
Under the direction of Dr. Lianna Johnson in Dr. Steve Jacobsen’s laboratory, Anuj will be purifying and characterizing methyl-DNA binding proteins thought to be involved as a cross-linker between DNA and histone methylation. These proteins are involved in epigenetic regulation, which are changes in gene expression that are not caused by changes in DNA sequence. Methyl Binding Domain (MBD) proteins in mammals are responsible for reading methylated DNA patterns and have been discovered to be associated with proteins that are important in transcriptional repression and/or heterochromatin formation by histone methylation. Homologues of histone methyltransferases in Arabidopsis are thought to contain a methyl binding domain and do not require the initial DNA binding protein to methylate histones.
Techniques such as Polymerase Chain Reaction, bacterial transformation, minipreps, and protein purification are used to produce and isolate the Arabidopsis SUVH methyltransferase proteins thought to be involved in this process of epigenetic regulation.
After isolation of the proteins, characterization will be done by a technique called Gel Shifts to observe which type of DNA residues each protein has specificity to and whether or not the proteins bind to methylated DNA.
Mr. Sean Tsao
Mentor: Dr. Yi Eve Sun
Funding: Wasserman Scholar
Title: Dynamic Covalent Exchange and Selection of Interlocked Molecules
(from left to right) Dr. Yi Eve Sun, Sean, Dr. Volkan Coskun
Sean Tsao is a fourth-year Neuroscience major and Public Policy minor at UCLA. He also is a tutor of Life Science 4 at the Advanced Academic Placement Program in the Math Science lab. Sean devotes the rest of his time towards the pre-health professional honor society, Alpha Epsilon Delta, where he currently serves as president.
Sean works under the guidance and supervision of Dr. Volkan Coskun in the laboratory of Dr. Yi Eve Sun, Department of Molecular & Medical Pharmacology. Sean’s project will characterize the role of the subventricular CD133+ neural stem cell in brain cancer. According to the cancer stem cell hypothesis, only a small population of cancerous cells contributes to the growth and maintenance of a tumor. This subpopulation is composed of cancer stem cells, which probably derive from mutated or dysfunctional multipotent stem cells. Several studies have implicated that CD133+ cells are tumorgenic in brain cancers, implicating the CD133+ neural stem cell as a potential cancer stem cell.
Sean and Dr. Coskun have been studying and establishing the CD133+ ependymal cell as a neural stem cell in the subventricular zone (SVZ). These CD133+ neural stem cells divide throughout adult life and their progeny migrate to the olfactory bulb where they mature and integrate into the neural circuitry. The idea behind the cancer stem cell hypothesis is that these normally functional neural stem cells become mutated and dysregulated, dividing out of control and becoming a tumor. To study the CD133 neural stem cell and its potential role as a cancer stem cell, Sean will create several lines of transgenic mice that lack tumor suppressor genes and overexpress tumorgenic genes. Specifically, these mice will created by crossing a CD133-Cre/GFP line with a PTEN lox-Kras stop/lox transgenic line. The resulting transgenic mouse will conditionally delete tumor suppressor gene PTEN while allowing constitutive expression of oncogene Kras in CD133+ cells. Thus, only CD133+ cells will be tumorgenic, allowing immunohistochemical analysis of the resulting tumor. The results of this study will be useful in developing future therapeutic strategies for addressing cancers. Targeted destruction of cancer stem cells may prove more effective than indiscriminate destruction of the tumors.
Sean enters his second year of tutoring LS 4 at the Advanced Academic Placement Program in Campbell Hall. He enjoys LS 4 for the challenge of tutoring an intriguing subject with many modern day applications. It is an added pleasure to tutor LS 4 for its relevance to the neurogenetic techniques employed in Sean’s lab. Finally, Sean is privileged to work with the best and brightest Life Science students who end up teaching him a lot more than he teaches them!
Sean is very thankful for the opportunities and experiences afforded to him by concurrently tutoring and performing research. He would like to thank Emmanuel Owaka, the Math Sciences lab coordinator, for allowing Sean the opportunity to teach and be taught at the Advanced Academic Placement program. Sean would like to extend his heartfelt thanks and gratitude to Dr. Volkan Coskun and Dr. Yi Eve Sun for their mentorship and guidance – and most of all for inculcating his deep interest in research. Finally, Sean would like to thank Dr. Audrey Cramer, the Undergraduate Research Center and the Wasserman Foundation for supporting his passion for teaching and science.
Ms. Bella Zaghi
*Profile removed upon request*
