Zikiar Alvin Savannah, GA Savannah State University Junior Biology Faculty Mentor: Peter Brink, Professor Department of Physiology and Biophysics
I Innexins, Connexins, and the Evolution of Intercellular Communication ZIKIAR V. ALVIN(1), PETER BRINK(2) TOM WHITE(2), HAUN WANG(2) It has long been known that protein channels called gap junctions facilitate both the ionic and biochemical intercellular communication in vertebrates. The subunit proteins responsible are referred to as connexins. Interestingly, in the invertebrates functionally analogous proteins called innexins have been found to perform the same functions but have no sequence identity with the connexin family of proteins. A further curiosity is the apparent lack of connexins in the invertebrates and likewise a lack of innexins in the vertebrates. Tunicates in the subphylum Urochordata represent the most advanced invertebrates. In the genome of the tunicate Sea Peach Halocynthia Pyriformis have found a sequence similar to a number of connexins. To further understand the evolution of connexins and innexins, I have used PCR methods to determine if there are any connexin-like sequences in the Nudibranch , Coryphelia verruscosa, in the phylum Mollusca and the starfish, Asteria rubens, in the phylum Echinoderm. I am going to attempt to determine if connexins and innexins represent an example of convergent evolution. (1)Department of Science and Technology, Savannah State University (SSU), Savannah, GA 31404 (2)Department of Physiology and Biophysics , Stony Brook University, Stony Brook, NY 11794-8661
ΔTOP
	Omar Armstrong Jersey City, NJ Polytechnic University First Year Master Biomedical Engineering Faculty Mentor: Suzanne Scarlata, Professor Department of Physiology & Biophysics
Resolving How the Pleckstrin Homology Domain of a Phospholipase C-B2 Interacts With BG Subunits of Heterotrimeric G Proteins OMAR K. ARMSTRONG, GUILLAUME DRIN, JOHN J. G. TESMER Phospholipase Cs (PLCs) play key roles in events leading to cell growth, division or death. Almost all cells contain 4 types of PLCs that are regulated differently. Our lab is interested in PLC-b², which is activated by G proteins and transduces signals from hormones and neurotransmitters. PLCs all contain an N-terminal Pleckstrin Homology (PH) domain. The PH domain of PLC has been found to be a tethering device that is both responsible for membrane localization and enzymatic regulation of Gbg subunits. To better understand the role of this domain in PLC function, the PH domain of PLC-b² was engineered into PLC-d¹ minus its own PH domain. We based this experiment on studies of b-adrenergic receptor kinase or GRK² and its PH domain. By x-ray crystallography GRK² was discovered to have regions in the PH domain that specifically interact with Gbg. Further, GRK² has homologous regions to the PLC-b² PH domain, which led to the present investigation of what affects will specific mutations made in the PLC-b² PH domain have on its interaction with Gbg. Through site directed mutagenesis technology, mutations were made in the PH domain of PLC-b² to change amino acid residues that we predict correspond to the specific interacting regions with Gbg. We predict a decrease in the binding of PLC-b² PH domain with Gbg subunits and a subsequent decrease in the activation of PLC-b² by Gbg will occur as a result of these mutations. ¹"Differential Association of the Pleckstrin Homology Domains of Phospholipases C-b1, C-b2 and C-d1 with Lipid Bilayers and the bg Subunits of Heterotrimeric G Proteins." (1999) Wang, T., Pentyala, S., Rebecchi, M. and Scarlata, S. Biochemistry 38, 1517-1524. ² "Keeping G proteins at bay: a complex between G protein-coupled receptor kinase 2 and Gbetagamma." (2003) Lodowski DT, Pitcher JA, Capel WD, Lefkowitz RJ, Tesmer JJ. Science 300, 1256-1262 ³ "Determination of strength and specificity of membrane-bound G protein--phospholipase C association using fluorescence spectroscopy." (2002) Scarlata, S. Methods in Enzymology 345, 307-327
ΔTOP
	Kamal Barley Brooklyn, New York Medgar Evers College Junior Mathematics Faculty Mentor: Anthony Phillips, Professor Department of Mathematics
Parallel Transport and Curvature in Differential Geometry and Theorical Physics KAMAL BARLEY(1), ANTHONY PHILLIPS(2) The goal of the project was the clarification of the relationship between parallel transport and curvature in differential geometry and in theoretical physics (Gauge Theory). A Maple program was developed to provide a visual support for understanding the geometric notions of parallel transport and curvature. The Gauss-Bonnet formula was used as the basic mathematical tool for relating parallel transport along a closed curve to the total curvature enclosed by the curve. The program developed can illustrate parallel transport around a geodesic triangle or an arbitrary circle of latitude on a sphere of radius 1. This work provides a visual representation between the curvature of a surface and the geometry of parallel transport along curves on that surface. The Aharonov-Bohm experiment (proposed in 1957 and performed in 1960) reveals a surprising phenomenon in electrodynamics. An electron beam is split; when the two halves are brought together again, they are out of phase by an amount proportional to the magnetic flux through the area they enclose. The last part of the project is an explanation of the Aharonov-Bohm experiment in terms of curvature and parallel transport. (1)Department of Mathematics, CUNY-Medgar Evers College, Brooklyn, NY (2)Department of Mathematics, Stony Brook University, Stony Brook, NY 11794-3651
ΔTOP
	Brandon Bell Mitchellville, MD University of Maryland Junior Biology Faculty Mentor: Daniel Dykhuizen, Professor Department of Ecology & Evolution
Disseminated Infection in the Hearts of Blarina Brevicada by Borrelia Burdorferi BRANDON C. BELL(1) DUSTIN BRISSON(2) AND DANIEL E. DYKHUIZEN(2) The purpose of our study is to examine polymorphisms at the outer surface protein C (ospC) locus of Borrelia burgdorferi at sites of disseminated tissue infection. B. burgdorferi, the causative agent of Lyme disease is maintained in an obligate enzootic cycle between Ixodes scapularis tick vectors and vertebrate hosts. B. burgdorferi enters a host at the site of a tick bite and disseminates to secondary sites early in infection while the skin infection is cleared early. ospC is one of the most variable loci in the B. burgdorferi genome, with 17 allelic groups found in nearly every population sampled in the northeastern United States. In our study we investigated the ability of B. burgdoferi with different alleles to disseminate to heart tissue of the mammal Blarina brevicada. We found that eight of the allele types could disseminate to the heart. Six of these eight allele types disseminated to the majority (> 60%) of the hearts of every shrew investigated. This suggests that shrews are either not infected with the other types that are found in tick nymphs or that B. burgdorferi with different ospC alleles may have tissue tropisms. (1)Biology Department, University of Maryland Baltimore County, Baltimore, MD 21250 (2)Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY 11794
ΔTOP
	Akua Bonsra Brentwood, MD University of Maryland Junior Biochemistry Faculty Mentor: David Williams, Professor Department of Molecular Pharmacology
Detection of Atherosclerotic Lesions of Paraffin-Embedded Mice Brachial Arteries by Immunohistochemistry AKUA BONSRA(1), FAYANNE THORNGATE(2), AND DAVID WILLIAMS(2) Atherosclerosis is a disease in which cholesterol accumulates in the arterial wall as plaque or lesions, blocking blood flow until a clot forms causing a heart attack or stroke. Apolipoprotein E (apoE) serves as a ligand for all the low-density lipoprotein (LDL) receptors which, when bound, allows the uptake of cholesterol and fatty acids. Previous work in the laboratory showed that low levels of apoE in transgenic mice can protect them from the accumulation of cholesterol ester in their arteries. We investigated mouse brachial arteries using immunohistochemistry with antibodies to detect macrophages and smooth muscle cells that are found in lesions. Mounted tissue slices were deparaffinized and fixed before being treated with a series of antibodies. For these experiments we used two different mice models: knockout mice (no apoE) and transgenic knockout mice (apoE produced only in adrenal gland). This technique will later be used to measure the relative numbers of macrophages and smooth muscle cells in the lesions and determine if the low level of apoE prevents their accumulation. (1)Department of Chemistry and Biochemistry, University of Maryland, Baltimore County, Baltimore, MD 21250 (2)Department Molecular Pharmacology, Stony Brook University, Stony Brook, NY 11790-8651
ΔTOP
	Yanique Bunsie Laurelton, NY Stony Brook University Junior Biology Faculty Mentor: Carol Carter, Professor Department of Molecular Genetics and Microbiology
HIV-1 GAG'S Interaction with Specific Cellular Membranes in Viral Assembly YANIQUE L. BUNSIE, ARTHUR J. GOFF, AND CAROL CARTER The human immunodeficiency virus (HIV) is the virus that causes AIDS. The virus is composed of nine genes that contribute to different stages of the viral life cycle. The gag gene is responsible for the assembly function of the virus. Assembly is the process by which the gag encoded Gag polyprotein moves through the cytoplasm to the cell surface and out of the cell. The Gag protein contains all of the information necessary to achieve assembly and release from infected cells. It is believed that during the assembly process the Gag protein interacts with specific cellular membranes. To investigate the location of the Gag protein in reference to the various cellular membranes, we are using confocal microscopy and fluorescent biochemical markers to label membranes first in cells not expressing gag and then examining for co-localization of gag and the markers in cells that are expressing gag. The identification of particular membranes that are relevant to the viral life cycle might provide a means for developing new treatments for HIV patients. Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11790-5222
ΔTOP
	Andrea Cyphers San Antonio, TX Grambling State University Sophomore Biology Faculty Mentor: Stella Tsirka, Associate Professor Department of Molecular Pharmacology
Tissue Plasminogen Activator Domain Deletion ANDREA CYPHERS(1) AND STELLA TSIRKA(2) Tissue plasminogen activator (tPA) is a clot dissolving, proteolytic enzyme that is naturally produced in cell walls of blood vessels and is known for catalyzing the conversion of plasminogen to plasmin. tPA has five domains: the Finger Domain, the Growth Factor Domain, two Kringle Module Domains, and finally the Serine Protease Domain. Each domain has its own specific role. In the central nervous system tPA is made by neurons and microglia. Microglia are small glia cells that migrate through nerve tissue and remove cell waste products. Previous studies have shown that when activated, microglia are involved in neuronal death. Damaged or dead neurons and activated microglia are present in several neurodegenerative diseases for example, Alzheimer's, Parkinson's, glaucoma, and ischemia. Work from our lab has determined that tPA is not only produced by microglia, but also affects their activation through its finger domain. Since the finger domain may not be the only one affecting activation, we focused on the deletion of two domains, the Finger Domain and the Growth Factor Domain, in order to determine their functions and observe if the activation of microglia still takes place. We are making the deletion construct using PCR, digestion, and ligation. We will later transfect the mutant tPA in the EGFP vector in mammalian cells. (1)Department of Biology, Grambling State University, Grambling, LA 71245 (2)Department of Molecular Pharmacology, Stony Brook University, Stony Brook, NY 11790-8651
ΔTOP
	Nicole Dujon Silver Spring, MD University of Maryland Junior Chemistry Faculty Mentor: Peter Gergen, Professor Department of Biochemistry and Cell Biology
Investigation of Y-Family Polymerase; Pol i NICOLE DUJON(1) AND HOLLY MILLER(2) DNA polymerases are the molecules responsible for the replication of DNA as cells multiply. Most DNA polymerases are highly accurate; they make very few mistakes and are able to correct those that are made. Recently a new family of DNA polymerases has been discovered in eukaryotes; the Y-family, composed of DNA polymerases k, h, and i. There has been evidence to support that these DNA polymerases have functions beneficial in DNA repair. Polymerase i is of particular interest because very little is known of its in vivo functions except that, unlike other related proteins, it makes very specific errors during replication that it is unable to correct. It may be possible for pol i to work with another DNA polymerase in its Y-family to fill gaps in replicated strands of DNA; often a causative factor in cancer. This work focuses on polymerase i. The RAD30B gene, which codes for pol i, was cloned into two vector constructs, pTYB¹ and pTYB², and over expressed in a host bacteria cell (E.coli strain BL21Ra1) using the IMPACT protein purification system. Once pol i is purified it will be possible to make antibodies for easier identification and solve its crystal structure. Observing the effects of this over expression may assist in determining what functional characteristics of pol i, may be helpful in cancer research; specifically cancers resulting from damaged DNA. (1)Department of Chemistry, University of Maryland Baltimore County, Baltimore, MD 21250 (2)Department of Molecular Pharmacology, Stony Brook University, Stony Brook, NY 11790-8651
ΔTOP
	Carlos Gamboa Laurel, NY Los Andes University B.S. Electrical Engineering Faculty Mentor: Thomas Robertazzi, Associate Professor Department of Electrical Engineering
Divisible Load Theory: A Sequential Sensitivity Study CARLOS F. GAMBOA, THOMAS G. ROBERTAZZI The sequencing problem involves optimizing the order in which a root processor should distribute divisible processing load to its children processors. The purpose of this procedure is to complete the processing of divisible load in a minimal amount of time or with a minimal energy use. Applications include third party computing services provided by Application Service Providers (ASPs), as well as wireless sensor networks. Four different heuristic algorithms were tested in order to achieve an efficient solution for the sequencing problem. Consequently, the optimum algorithm (Best Swap) was selected to implement the sensitivity analysis. Such analysis allowed an examination of the relationship between the total cost function, changes in the speed of the links and the processors, and changes in cost of processing and transmission. Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY 11794-2350
ΔTOP
	Severo Garcia San Fernando, CA California State University, Northridge Junior Electrical Engineering Faculty Mentor: Petar Djuric, Associate Professor Department of Electrical Engineering
Edge Detection of Synthetic Aperture Radar Images SEVERO GARCIA(1), PETAR M. DJURIC(2) Synthetic Aperture Radar (SAR) images are mainly used to provide terrain structural information. Despite the fact that multiplicative noise corrupts these images they are still a very popular form of imagery. Unfortunately, this noise gives rise to inadequate measurements of detecting the edges in the images. The goal of this work was to develop a protocol to eliminate the noise, thus enhancing SAR edge detection. Filtering of the multiplicative noise was performed prior to detection of SAR edges. Matlab was used to test different edge detection methods such as Sobel's, Robert's, Canny's and Prewitt's. These methods were implemented in SAR images. Results showed Canny's method to be more effective in detecting the edges. (1) California State University Northridge, 18111 Nordhoff Street, Northridge, California 91330 (2) Department of Electrical and Computer Engineering, Stony Brook University, Stony Brook, NY 11794-2350
ΔTOP
	Kawasi Lett Brooklyn, NY Kingsborough Community College (CUNY) Sophomore Biology Faculty Mentor: Peter Gergen, Professor Department of Biochemistry and Cell Biology
Quantitative Analysis Employing LacZ Reporter Genes in Early Drosophila Embryogenesis KAWASI LETT(1), DEBORAH SWANTEK(2), J. PETER GERGEN(2) Drosophila melanogaster serves as a good model for genetic studies because of its short life span and small genome size. Genetic manipulation enables us to use this model to understand the dynamics of gene expression. Our research focuses on using the modular GAL4 system in order to regulate gene expression in the early blastoderm stage of Drosophila embryogenesis. A promoter mediates the expression of the yeast transcription activator GAL4 (involved in the galactose pathway), and then directs transcription of the GAL4-responsive UAS target gene (upstream activator sequence). The distinctive characteristic of this system is that the GAL4 gene and the UAS target gene are initially separated into two distinct transgenic lines. By using flies that have different levels of maternal yeast transcription factor, GAL4, we can quantitatively manipulate the expression levels of our gene of interest in the UAS transgenic line. This model of gene expression enables us to insert virtually any gene into the UAS transgene construct, including genes that are not indigenous to the Drosophila melanogaster genome. We will be utilizing the bacterial gene lacZ, which encodes for the enzyme ß -galactosidase. ß -galactosidase will be ectopically expressed in the embryo, and the levels of gene expression can be quantified by the use of a chemiluminescent assay. Analysis of the results will indicate whether there is a correlation between the strength of the observed maternal GAL4 drivers and the ß -galactosidase activity. (1)Medgar Evers College, 1Kingsborough Community College, (2)Department of Biochemistry and Cell Biology and the Center for Cell and Developmental Genetics, Stony Brook University, Stony Brook, 11794-5140
ΔTOP
	Dwayne Mason Brooklyn, NY Savannah State University Senior Computer Science Faculty Mentor: Robert Kelly, Associate Chair Department of Computer Science
The Design and Implementation of an Internet-Based Interface for the Long Island Sound Marine and Atmospheric Observing System DWAYNE MASON, ROBERT KELLY, AMHA MOGUS, IRINA MIRETSKIY AND DAVID TURNER The Long Island Sound Marine and Atmospheric Observing System allows for the efficient storage, retrieval and display of environmental conditions data collected using sensors installed on a commuter ferry sailing the Long Island Sound. The success of a system such as this is contingent on the ability to engineer a "user-friendly" interface that makes efficient access to the data a reality for a diverse audience of prospective users. The growth in both the sheer size and popularity of the Internet, coupled with the consistent development of Internet-based technologies, makes it a suitable environment for the implementation of such an interface. Using markup languages, such as XHTML and XML, Cascading Style Sheets (CSS), and server-based technologies, such as Java beans, Java servlets and JavaServer Pages (JSP), an Internet-based interface for the Long Island Sound Marine and Atmospheric Observing System was designed and implemented. The interface, which is in this case a dynamic website, makes use of modular design techniques in order to separate content, presentation of content, and overall system control. The content to be displayed is encapsulated in Java beans, while the actual presentation and display are handled by JavaServer Pages. The control and sequencing aspects of the website are managed in large part by Java servlets. Arguably, the most successful and popular interfaces are those that also provide a unique presentation of the system's data. This interface is unique in that it allows for dynamically generated linear and contour plots of the stored data based on user request parameters. It also utilizes Java implemented image composition and transformation techniques to dynamically produce JPEG images. Department of Computer Science Stony Brook University, Stony Brook NY 11794-4400
ΔTOP
	Verrad Nyame Queens, NY Binghamton University Junior Biochemistry Faculty Mentor: Simon Halegoua, Associate Professor Department of Neurobiology and Behavior
Pincher Mediates Internalization and Transport of Neurotrophin Signaling Endosomes (1)VERRAD NYAME, (2)WENDY AKMENTIN, (2)GERGORIO VALDEZ, AND (2)SIMON HALEGOUA Nerve Growth Factor (NGF) is the prototypic member of the neurotrophin (NT) family of trophic factors, necessary for the growth and maintenance of nerve cells. A model has been proposed whereby the cell surface NT/receptor tyrosine kinase (Trk) complex is internalized at the nerve terminal into signaling vesicles (endosomes) and retrogradely transported to the cell body to mediate NT effects. However the internalization mechanism is poorly understood. An endocytic chaperone protein called Pincher has been shown to mediate the internalization of NGF and its Trk receptors in the rat neuronal model, PC12 cell. Overexpression of Pincher facilitates internalization of NGF/Trk endosomes. We studied Trk internalization and transport in this system using immuno-gold electron microscopy to localize both Pincher and Trk during the process. We found that Pincher and Trk initially found at the cell surface ruffles. Anti-Pincher immuno-gold labeling indicated that Pincher relocalizes to tubules seen in electron micrographs. Anti-Trk labeling was found with endosomes residing within tubules. These tubules appear to serve as conduits for NT/Trk endosomes. The tubules lead to vesicle accumulating bodies where NT and Trk receptors are concentrated. The Pincher tubules sorted independently from the vesicle accumulating bodies containing Trk. The Pincher tubules were found to return to the plasma membrane. This research provides insight into understanding the underlying causes of neurodegenerative diseases in which trophic factor function is impaired. (1)Department of Chemistry and Biochemistry, State University of New York at Binghamton, Binghamton, NY, 13902 (2)Department of Neurobiology and Behavior and Center for Brain and Spinal Cord Research, Stony Brook University, Stony Brook, NY 11794-5230
ΔTOP
	Joseph Ortiz Edinburg, TX University of Texas-Pan American Senior Mathematics Faculty Mentor: Steve Finch, Associate Professor Department of Applied Mathematics & Statistics
Frequency and Duration of Episodes in Major Depressive Disorder, the Prevalence of Mixed Episodes, and the Realtionship to Reported Anti-Depressants Administered JOSEPH N. ORTIZ(1), STEPHEN J. FINCH(2), QING YE2, EVELYN BROMET(3) A sample of 81 subjects with major depressive disorder (MDD) was provided by the Suffolk County Mental Health Project (SCMHP) to determine the number and length of episodes and the prevalence of mixed, hypomanic, and manic symptoms within the sample. Special precautions were taken with dysthymia, a moderate form of depression where patients are less likely to hurt themselves or others, and separate measurements were used to include it as a depressed symptom. Results showed that while MDD may last less than three months for about 30% of the sample, for 55%, depression was a recurring illness whose symptoms could be felt for over two years. It was found that roughly ten percent of these MDD patients presented mixed or manic mood symptoms at some time during the 48-month period, and consequently medicinal records were scanned in an attempt at finding a relationship between medicine and mania. The use of imipramine, an older, but still used, anti-depressant has been implicated with increased likelihood of manic symptoms. It was found that half of all patients to whom it was administered suffered from mixed or manic mood symptoms, and that half of the observed mixed or manic episodes followed the use of imipramine. (1) Department of Mathematics, University of Texas-Pan American (2) Department of Applied Mathematics and Statistics, Stony Brook University (3) Department of Psychiatry, Stony Brook University
ΔTOP
	Glenn Roach Queens, NY Stony Brook University Junior Electrical Engineering Faculty Mentor: Ridha Kamoua, Associate Professor Department of Electrical Engineering
Graphic Interface for a Monte Carlo Semiconductor Device Simulator GLENN P. ROACH JR., RIDHA KAMOUA In a typical Monte Carlo simulation of semiconductor devices, a large amount of data is obtained about the behavior of its electrons and holes. The amount of information obtained makes visualization of the dynamics that is taking place difficult to conceptualize. Creating a graphic interface allows the conversion of this data into a visual form that is easier to interpret. Opengl was chosen as a platform to render graphics for the Monte Carlo Simulator due to its ability to develop 2-Dimensional and 3-Dimensional images. The interfacing with the existing Monte Carlo program is achieved by developing a 3-Dimensional graphic routine which is called by the main program (i.e. Monte Carlo Semiconductor Device Simulator) after all the computations for a given time increment have been completed. Additionally, the main program written in Fortran 77 is converted to C/C++ to make it compatible with the graphic routine. Converting the main program to C/C++ makes passing data to the graphic routine a more efficient and easier process. In developing a graphic routine for this Monte Carlo Semiconductor Device Simulator will help with analyzing of Semiconductor Devices and allows the user to study the device during the simulation rather than after the simulation. Department of Electrical and Computer Engineering Stony Brook University, NY 11794-2350
ΔTOP
	Rose St Fleur Brooklyn, NY City College (CUNY) Junior Mathematics Faculty Mentor: Steve Finch, Associate Professor Department of Applied Mathematics and Statistics
A Comparison of the Effect of Genotyping Errors on the Power of the Armitage Trend Test and the 2x3 Chi-Squared Test in Di-Allelic Genetic Association Studies ROSE SAINT FLEUR(1), STEPHEN J. FINCH(2), DEREK GORDON(3), SUN JUNG KANG(2) We compared the effect of genotyping errors on the power of a 2x3 chi-squared test and the Armitage trend test applied to genetic association studies. Since these two tests are commonly used in these studies, we wanted to know which one of the two should be used for a specific sample by focusing on what happens to the power of both tests in the case that the sample has genotyping errors. For the experiment, the same significance level a was used with different allele frequencies having a 10% difference in allele frequency between case/control for the data with the assumption that both case and controls groups are in Hardy Weinberg Equilibrium. We considered a second scenario in which control genotype frequencies were in Hardy Weinberg Equilibrium and case genotype frequencies satisfied prevalence and penetrance parameters for a SNP in linkage disequilibrium with a disease gene. Then using the Mote Anderson error model, which contains six error parameters, we set both homozygote to heterozygote misclassification error rates to k, both heterozygote to homozygote misclassification error rates to k, and both homozygote to homozygote misclassification error rates to 0. Since the Type II Error b was not known, two separate computer programs were used to find the approximate power for both tests with and without genotyping error. The Armitage trend test is more powerful than the chi-squared when there is no genotyping error. The results also show that whenever the allele frequency decreases, the power of both tests increases for all the significance levels that were considered. The power of both test decreases as the genotyping error rate k increases, with the Armitage test losing power faster than the chi-squared test. When genotype frequencies were determined by a genetic model, the chi-squared test had power comparable to, if not better than, the Armitage test. Values of k for which both tests had approximately equal power were determined. (1)Department of Mathematics, City College of New York (2)Department of Applied Mathematics and Statistics, Stony Brook University (3)Laboratory of Statistical Genetics, Rockefeller University
ΔTOP
	Ashina Singh Gaithersburg, MD University of Maryland Sophomore Biochemistry Faculty Mentor: Mary F. Kritzer, Associate Professor Department of Neurobiology and Behavior
Distribution of Androgen and Estrogen Receptors in the Thalamus of Postnatal Male and Female Rats and Its Relevance to Autism ASHINA SINGH(1) AND MARY F. KRITZER(2) The purpose of this study is to map the distribution of androgen and estrogen receptors in the thalamus of infant male and female rats. The thalamus is a major integrating center; virtually all incoming information must pass through it to reach the cerebral cortex, the brain structure responsible for all higher order sensory, motor and cognitive information processing. The thalamus is also unique in that it is one of a very few brain areas that undergoes fundamental stages of development during postnatal life. For these reasons the thalamus is of interest in relation to the developmental disorder autism, where suspected cortical dysfunctions such as social interaction, language and other higher order faculties could be secondary to some insult to the thalamus during its vulnerable period early in postnatal life. The question of hormone receptor distribution in this structure also relates to autism in that there are clear sex differences in the prevalence of this disease with roughly four times as many males diagnosed as females. My hypothesis is that the posterior and mediodorsal nuclei of the thalamus, which project to cortical areas involved in the types of functions affected by autism, will express hormone receptors, perhaps transiently, in turn rendering these nuclei and the cortical areas they project to vulnerable to hormone manipulation. This scenario would be consistent with the developmental timing of autism, the types of symptoms involved in this disorder, and the sex differences seen in these deficits. Accordingly I am using immunoctyochemical-staining methods to localize receptors; I have already seen that estrogen receptors show a transient wave of expression in the thalamus in 5 to 7 day old male and female rats. Further investigation is underway to define whether the localization of the receptor is consistent with sex specific patterns of cortical deficits that are thought to underlie the behavioral problems such as social withdrawnness, impairment of sensory input processing and communication that are hallmarks of autism. (1)University of Maryland, Baltimore County (UMBC), Department of Chemistry and Biochemistry, Baltimore, MD 21250 (2) Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY 11794-5230
ΔTOP
	Danielle Williams Bronx, NY Stony Brook University Junior Biology Faculty Mentor: Eckard Wimmer, Professor Department of Molecular Genetics and Microbiology
Mutational Analysis of the 3´NTR of the Hepatitis C Virus Genome RNA in the Replication Process DANIELLE WILLIAMS, HAEKYUNG LEE, AND ECKARD WIMMER Previous studies have shown that the 3´ non-translated region (NTR) of the RNA genome of the Hepatitis C Virus (HCV) consists of a three part structure composed of a 40 nucleotide variable region, a polyuridine tract of variable length, and a 98-nucleotide sequence designated the X-tail that is highly conserved among all HCV genotypes and that is essential for replication. The 5´-and 3´NTRs of this positive strand RNA virus function as cis-acting elements important for translation and replication respectively. The 5´-terminal functions as an internal ribosome entry site (IRES) while the X-tail region of the 3´ NTR composes a specialized 3-component stem loop structure (SLI, SLII and SLIII) which is essential for RNA replication. In our lab it has been determined that the addition of extra sequences after the X-tail generates a lethal phenotype in the virus. In this study we propose that the addition of an extra X-tail after the additional sequences will rescue replication and elucidate the mechanism by which Hepatitis C Virus can achieve authentic replication initiation in the presence of a mutation created in the 3´ end of the HCV replicon. Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY 11794-5222
ΔTOP
	Oladapo Yeku Queens, NY Medgar Evers (CUNY) Sophomore Biology Faculty Mentor: Michael Frohman, Associate Professor Department of Molecular Pharmacology
Regulation and Function of Phospholipase D in Mast Cells OLADAPO YEKU(1) GUANGWEI DU(2) MICHAEL FROHMAN(2) Mast cells are immune cells that originate from precursors of the haematopoietic lineage and circulate in the blood and lymphatic system. Their distinctive quality is the possession of an IgE (immunoglobulin- e) receptor that enables them to interact with antigens. The antigen- IgE-receptor complex triggers the cell to release histamine. Two Phospholipase D (PLD) family members, PLD1 and PLD2, have been identified in mammalian cells. Both PLD1 and PLD2 are expressed in mast cells but are thought to be involved in different stages of degranulation, based on studies using overexpression of wild-type and mutant proteins. My first goal is to focus on how the subcellular localizations of PLD1 and PLD2 are regulated, using a series of mutated alleles that alter PLD associations with membrane lipids and protein partners. I will also examine whether histamine release is altered in PLD1 down-regulated cells, using a cell line stably transformed with a PLD1 RNAi-generating plasmid. A better understanding of the regulation of PLD localization in mast cells and the roles it undertakes in degranulation will further our understanding of chronic allergy and anaphylaxis. (1)Medgar Evers College, Brooklyn, New York 11225, and (2)Department of Molecular Pharmacology, Stony Brook University, Stony Brook, New York 11794-5140