Digital Commons Network^™

Bcma Is Essential For The Survival Of Long-Lived Bone Marrow Plasma Cells, Brian P. O'Connor, Vanitha S. Raman, Loren D. Erickson, W. James Cook, Lehn K. Weaver, Cory Ahonen, Ling-Li Lin, George Mantchev, Richard J. Bram, Randolph J. Noelle

Dartmouth Scholarship

Long-lived humoral immunity is manifested by the ability of bone marrow plasma cells (PCs) to survive for extended periods of time. Recent studies have underscored the importance of BLyS and APRIL as factors that can support the survival of B lineage lymphocytes. We show that BLyS can sustain PC survival in vitro, and this survival can be further enhanced by inter- leukin 6. Selective up-regulation of Mcl-1 in PCs by BLyS suggests that this 􏰀-apoptotic gene product may play an important role in PC survival. Blockade of BLyS, via transmembrane activator and cyclophilin ligand interactor–immunoglobulin treatment, inhibited PC survival in …

Effect Of Culture Medium Volume On The Development And Viability Of Microinjected Or Noninjected One-Cell Hybrid And Cd-1 Strain Mouse Embryos, Haydar Bağiş, Hande Odaman Mercan

Turkish Journal of Veterinary & Animal Sciences

We investigated the effects of drop volume on the development of mouse presumptive zygotes to the completely hatched blastocyst stage. For this aim, we established 3 experimental groups. In the first group, we cultured hybrid presumptive zygotes to the hatched blastocyst stage in 10 presumptive zygotes per 5, 10, 20, 40 and 50 µl drops. In the second group, we used microinjected hybrid zygotes for culture. In the last group, we cultured CD-1 mouse presumptive zygotes to the hatched blastocyst stage. There was no statistical difference in the first group. In contrast, the data demonstrated that there were significant differences …

A Scanning Electron Microscope Examination Of Heligmosomum Costellatum, Kader Yildiz, Külti̇gi̇n Çavuşoğlu

Turkish Journal of Veterinary & Animal Sciences

The morphology of Heligmosomum costellatum, a nematode of field mice (Microtus epiraticus), was described by scanning electron microscope. The scanning electron microscopic view of this nematode revealed that the anterior end was surrounded by 2 cephalic vesicles. The 2 copulatory spicules of the male were enveloped in membrane and the male bursa was large. The female posterior end was characterized by a caudal spine. The body of this parasite had transverse ridges.

Characterization Of Insulin-Like Growth Factor Binding Protein-2 Secretion In Mouse Mesangial Cells, Marianne Ellen Albert

MUSC Theses and Dissertations

Dysregulation of the insulin-like growth factor (IGF) system plays a key role in the hyperproliferative state seen in diabetic complications. Enhanced IGF-I activity plays a causal role in diabetic glomerulosclerosis (DG) by stimulating mesangial cell proliferation, secretion and hypertrophy. Other alterations of the IGF system may include increased IGF-I receptor (IGF-IR) and increased IGF binding protein (IGFBP) expression. The IGFBP family consists of six soluble binding proteins, IGFBP 1-6, which have higher affinities for the IGFs than the IGF-IR, resulting in blocking IGF access to the IGF-IR. Since the IGFBPs primarily function to inhibit IGF action, we hypothesize that overexpression …

Molecular Characterization Of Immunoglobins A, G, And M Heavy Chains In The Atlantic Bottlenose Dolphin, Tursiops Truncatus, Holly Ann Gefroh

MUSC Theses and Dissertations

The dolphin immune system is not well characterized, unlike the human and mouse immune systems. As a sentinel species of the marine ecosystem, an understanding of the dolphin immune system will not only contribute to conservation and management of the species, but also contribute to an understanding of the status of the marine ecosystem. cDNA sequences encoding IgA and IgG heavy chains and IgM transmembrane segment of the Atlantic bottlenose dolphin, Tursiops truncatus, were obtained using a combination of reserve transcription of mRNA, PCR amplification using degenerate primers, and 3' and VH-FR3 anchored 5' RACE. Analysis of dolphin γ gene …

Inactivation Of A Bacterial Virulence Pheromone By Phagocyte-Derived Oxidants: New Role For The Nadph Oxidase In Host Defense, Jacob M. Rothfork, Graham S. Timmins, Michael N. Harris, Xian Chen, Aldons J. Lusis, Michael Otto, Ambrose L. Cheung, Hattie D. Gresham

Dartmouth Scholarship

Quorum sensing triggers virulence factor expression in medically important bacterial pathogens in response to a density-dependent increase in one or more autoinducing pheromones. Here, we show that phagocyte-derived oxidants target these autoinducers for inactivation as an innate defense mechanism of the host. In a skin infection model, expression of phagocyte NADPH oxidase, myeloperoxidase, or inducible nitric oxide synthase was critical for defense against a quorum-sensing pathogen, Staphylococcus aureus, but not for defense against a quorum sensing-deficient mutant. A virulence-inducing peptide of S. aureus was inactivated in vitro and in vivo by reactive oxygen and nitrogen intermediates, including HOCl and ONOO(-). …

Slbp Is Associated With Histone Mrna On Polyribosomes As A Component Of The Histone Mrnp, Michael L. Whitfield, Handan Kaygun, Judith A. Erkmann, W. H. Davin Townley-Tilson, Zbig Dominski, William F. Marzluff

Dartmouth Scholarship

The stem–loop binding protein (SLBP) binds the 3′ end of histone mRNA and is present both in nucleus, and in the cytoplasm on the polyribosomes. SLBP participates in the processing of the histone pre-mRNA and in translation of the mature message. Histone mRNAs are rapidly degraded when cells are treated with inhibitors of DNA replication and are stabilized by inhibitors of translation, resulting in an increase in histone mRNA levels. Here, we show that SLBP is a component of the histone messenger ribonucleoprotein particle (mRNP). Histone mRNA from polyribosomes is immunoprecipitated with anti-SLBP. Most of the SLBP in cycloheximide-treated cells …

Detection And Mapping Of Quantitative Trait Loci That Determine Responsiveness, Janet L. Mueller, E. A. Ellenberger, Linda K. Vaughn, John K. Belknap, Raymond M. Quock

Biomedical Sciences Faculty Research and Publications

Exposure to 70% N₂O evokes a robust antinociceptive effect in C57BL/6 (B6) but not in DBA/2 (D2) inbred mice. This study was conducted to identify quantitative trait loci (QTL) in the mouse genome that might determine responsiveness to N₂O. Offspring from the F₂ generation bred from B6 and D2 progenitors exhibited a broad range of responsiveness to N₂O antinociception as determined by the acetic acid-induced abdominal constriction test. QTL analysis was then used to dissect this continuous trait distribution into component loci, and to map them to broad chromosomal regions. To this end, …

Pathological Findings In Acute Amitraz Intoxication In Mice, Ayhan Fi̇lazi̇, Tolga Güvenç, Cavi̇t Kum, Seli̇m Sekki̇n

Turkish Journal of Veterinary & Animal Sciences

This study examined the pathological changes in tissues and organs with acute intoxications with amitraz and its veterinary medicinal formulation. In total 312 healthy white English mice (Mus musculus), 156 female and 156 male, were used for this purpose. The solutions were given to the mice by gavage at the following dosages: 500, 1000, 1500, 1800, 2200 or 2500 mg of technical amitraz/kg and 50, 100, 250, 500, 750 or 1000 mg of amitraz/kg in a veterinary formulation. There was an interval of 1 week after the administration of the study medication. Necropsies were performed immediately on the mice that …

Topical Cidofovir Is More Effective Than Is Parenteral Therapy For Treatment Of Progressive Vaccinia In Immunocompromised Mice, Donald F. Smee, K. W. Bailey, M-H. Wong, M. K. Wandersee, R. W. Sidwell

Animal, Dairy, and Veterinary Science Faculty Publications

Background.Severe complications may arise as a result of virus dissemination after smallpox (live vaccinia virus) vaccination, particularly in immunocompromised individuals. We developed a new mouse model for studying the effects of antiviral agents on progressive vaccinia virus infections.

Methods.Hairless mice were treated with cyclophosphamide (100 mg/kg/day) every 4 days starting 1 day before vaccinia virus exposure to wounded skin. Primary lesions progressed in severity, satellite lesions developed, and the infection eventually killed the mice.

Results.Topical treatment with 1%‐cidofovir cream (twice daily for 7 days) was much more effective in reducing the severity of primary lesions and the number of satellite …

Impaired Antigen Receptor Induced Calcium Mobilization In A Phospholipase C-Gamma1 Deficient B Cell Line., Natarajan Muthusamy, Do Joon Park, Hei-Won Rho, Sue Goo Rhee, Subbarao Bondada

Microbiology, Immunology, and Molecular Genetics Faculty Publications

B lymphocytes express phospholipase C-gamma(1) (PLC-gamma(1)) and phospholipase C-gamma(2) (PLC-gamma(2)) isozymes. However, the relative importance of these two isozymes in B cell signaling is not known. We report here the identification and analysis of a B cell line deficient in PLC-gamma(1). Mature splenic B lymphocytes and a panel of cell lines representing pre-B, immature and mature B cell stages expressed phospholipase C-gamma (PLC-gamma), but not the beta or delta isoforms of phospholipase C (PLC). While all the tested B cell lines and primary splenic B cells expressed PLC-gamma(1) and PLC-gamma(2) isozymes, the L1.2 B cell line exclusively expressed PLC-gamma(2), but …

Oncolog, Volume 48, Number 12, December 2003, Karen Stuyck, Dawn Chalaire, Martha A. Askins, Martha Aschenbrenner

OncoLog MD Anderson's Report to Physicians (All issues) Archives

• On the Move: Efforts Under Way to Improve Outcomes for Patients with Renal Cancer
• Protocols: Studies Examine Treatments for Renal Cell Carcinoma
• Art Therapy Helps Children Affected by Cancer Express Their Emotions
• Children's Art Project Has Been Improving the Lives of Children with Cancer for 30 Years
• DiaLog: When a Parent Is Sick: Talking to Children about Cancer, by Martha A. Askins, PhD, Division of Pediatrics, and Martha Aschenbrenner, Director, Child Life Services

The Stromal Cell-Derived Factor-1alpha/Cxcr4 Ligand-Receptor Axis Is Critical For Progenitor Survival And Migration In The Pancreas., Ayse G. Kayali, Kurt Van Gunst, Iain L. Campbell, Aleksandr Stotland, Marcie Kritzik, Guoxun Liu, Malin Flodström-Tullberg, You-Qing Zhang, Nora Sarvetnick

Journal Articles: Regenerative Medicine

The SDF-1alpha/CXCR4 ligand/chemokine receptor pair is required for appropriate patterning during ontogeny and stimulates the growth and differentiation of critical cell types. Here, we demonstrate SDF-1alpha and CXCR4 expression in fetal pancreas. We have found that SDF-1alpha and its receptor CXCR4 are expressed in islets, also CXCR4 is expressed in and around the proliferating duct epithelium of the regenerating pancreas of the interferon (IFN) gamma-nonobese diabetic mouse. We show that SDF-1alpha stimulates the phosphorylation of Akt, mitogen-activated protein kinase, and Src in pancreatic duct cells. Furthermore, migration assays indicate a stimulatory effect of SDF-1alpha on ductal cell migration. Importantly, blocking …

Transcriptional Inhibition Of Type I Collagen Gene Expression In Scleroderma Fibroblasts By The Antineoplastic Drug Ecteinascidin 743., Natalia Louneva, Biagio Saitta, David J Herrick, Sergio A. Jimenez

Department of Medicine Faculty Papers

We previously showed that COL1A1 expression is up-regulated at the transcriptional level in systemic sclerosis (SSc) fibroblasts and that the CCAAT-binding factor (CBF) is involved in this increased expression. Ecteinascidin 743 (ET-743) is a chemotherapeutic agent that binds with sequence specificity to the minor groove of DNA and inhibits CBF-mediated transcriptional activation of numerous genes. Therefore, we examined the effects of ET-743 on the increased COL1A1 expression in SSc fibroblasts. The drug caused a potent and dose-dependent inhibition of type I collagen biosynthesis, which reached 70-90% at 700 pM without affecting cell viability. The same drug concentration caused 60-80% reduction …

Identification Of App1 As A Regulator Of Phagocytosis And Virulence Of Cryptococcus Neoformans, Chiara Luberto, Beatriz Martinez-Mariño, Daniel Taraskiewicz, Benjamin Bolaños, Pasquale Chitano, Dena L. Toffaletti, Gary M. Cox, John R. Perfect, Yusuf A. Hannun, Edward Balish, Maurizio Del Poeta

MUSC Faculty Journal Articles

Cryptococcus neoformans is a fungal pathogen that, after inhalation, can disseminate to the brain. Host alveolar macrophages (AMs) represent the first defense against the fungus. Once phagocytosed by AMs, fungal cells are killed by a concerted mechanism, involving the host-cellular response. If the cellular response is impaired, phagocytosis of the fungus may be detrimental for the host, since C. neoformans can grow within macrophages. Here, we identified a novel cryptococcal gene encoding antiphagocytic protein 1 (App1). App1 is a cryptococcal cytoplasmic protein that is secreted extracellularly and found in the serum of infected patients. App1 does not affect melanin production, …

Il-7 Enhances Peripheral T Cell Reconstitution After Allogeneic Hematopoietic Stem Cell Transplantation., Onder Alpdogan, Stephanie J Muriglan, Jeffrey M Eng, Lucy M Willis, Andrew S Greenberg, Barry J Kappel, Marcel R M Van Den Brink

Department of Medical Oncology Faculty Papers

We used clinically relevant murine allogeneic bone marrow transplantation (BMT) models to study the mechanisms by which IL-7 administration can improve posttransplant peripheral T cell reconstitution. After transplant we could distinguish two populations of mature donor T cells: (a) alloreactive T cells with decreased expression of CD127 (IL-7 receptor alpha chain) and (b) nonalloreactive T cells, which express CD127 and undergo homeostatic proliferation. IL-7 administration increased the homeostatic proliferation of nonalloreactive T cells, but had no effect on alloreactive T cells and the development of graft-versus-host disease. Allogeneic transplant of purified hematopoietic stem cells and adoptive transfer of thymocytes into …

A Null Mutation For Tissue Inhibitor Of Metalloproteinases-3 (Timp-3) Impairs Murine Bronchiole Branching Morphogenesis., Sean E Gill, M Cynthia Pape, Rama Khokha, Andrew J Watson, Kevin J Leco

Obstetrics & Gynaecology Publications

Tissue inhibitors of metalloproteinases (TIMPs) regulate extracellular matrix (ECM) degradation by matrix metalloproteinases (MMPs). We have examined the role of TIMP-3 on ECM homeostasis and bronchiole branching morphogenesis during murine embryogenesis. Employing an in vitro organ culture system, we found decreased bronchiolar branching in null lungs when compared with wild type (WT) counterparts after 2 days in culture. When a synthetic inhibitor of MMPs at low dose was added to the culture system, branching was augmented regardless of genotype. Gelatin and in situ zymography revealed that null lungs exhibited enhanced activation of MMPs throughout lung development. We analysed the impact …

Vegf164-Mediated Inflammation Is Required For Pathological, But Not Physiological, Ischemia-Induced Retinal Neovascularization, Susumu Ishida, Tomohiko Usui, Kenji Yamashiro, Yuichi Kaji, Shiro Amano, Yuichiro Ogura, Tetsuo Hida, Yoshihisa Oguchi, Jayakrishna Ambati, Joan W. Miller, Evangelos S. Gragoudas, Yin-Shan Ng, Patricia A. D'Amore, David T. Shima, Anthony P. Adamis

Ophthalmology and Visual Science Faculty Publications

Hypoxia-induced VEGF governs both physiological retinal vascular development and pathological retinal neovascularization. In the current paper, the mechanisms of physiological and pathological neovascularization are compared and contrasted. During pathological neovascularization, both the absolute and relative expression levels for VEGF₁₆₄ increased to a greater degree than during physiological neovascularization. Furthermore, extensive leukocyte adhesion was observed at the leading edge of pathological, but not physiological, neovascularization. When a VEGF₁₆₄-specific neutralizing aptamer was administered, it potently suppressed the leukocyte adhesion and pathological neovascularization, whereas it had little or no effect on physiological neovascularization. In parallel experiments, genetically altered VEGF_{164 …}

Probucol Prevents Early Coronary Heart Disease And Death In The High-Density Lipoprotein Receptor Sr-Bi/Apolipoprotein E Double Knockout Mouse, Anne Braun, Songwen Zhang, Helena E. Miettinen, Shamsah Ebrahim, Teresa M. Holm, Eliza Vasile, Mark J. Post

Dartmouth Scholarship

Mice with homozygous null mutations in the high-density lipoprotein receptor SR-BI (scavenger receptor class B, type I) and apolipoprotein E genes fed a low-fat diet exhibit a constellation of pathologies shared with human atherosclerotic coronary heart disease (CHD): hypercholesterolemia, occlusive coronary atherosclerosis, myocardial infarctions, cardiac dysfunction (heart enlargement, reduced systolic function and ejection fraction, and ECG abnormalities), and premature death (mean age 6 weeks). They also exhibit a block in RBC maturation and abnormally high plasma unesterified-to-total cholesterol ratio (0.8) with associated abnormal lipoprotein morphology (lamellar/vesicular and stacked discoidal particles reminiscent of those in lecithin/cholesterol acyltransferase deficiency and cholestasis). Treatment …

Natural Selection On Protein Polymorphism In The Rodent Genus Peromyscus: Evidence From Interlocus Contrasts, Jay F. Storz, Michael W. Nachman

Jay F. Storz Publications

The effects of natural selection are generally locus-specific, whereas migration, drift, and inbreeding are expected to have relatively uniform effects across the entire genome. This suggests that multilocus surveys of multiple populations can be used to distinguish selection from demographic effects. The purpose of this study was to test for evidence of selection on protein polymorphism in natural populations of mice in the genus Peromyscus. We analyzed published data from geographic surveys of allozyme variation and used a coalescent- based simulation model to identify specific loci that deviated from neutral expectations. Observed F_ST values generally exhibited a remarkably …

Aquaporin Proteins In Murine Trophectoderm Mediate Transepithelial Water Movements During Cavitation., Lisa C Barcroft, Hanne Offenberg, Preben Thomsen, Andrew J Watson

Obstetrics & Gynaecology Publications

Mammalian blastocyst formation is dependent on establishment of trophectoderm (TE) ion and fluid transport mechanisms. We have examined the expression and function of aquaporin (AQP) water channels during murine preimplantation development. AQP 3, 8, and 9 proteins demonstrated cell margin-associated staining starting at the 8-cell (AQP 9) or compacted morula (AQP 3 and 8) stages. In blastocysts, AQP 3 and 8 were detected in the basolateral membrane domains of the trophectoderm, while AQP3 was also observed in cell margins of all inner cell mass (ICM) cells. In contrast, AQP 9 was predominantly observed within the apical membrane domains of the …

Mammalian Erv46 Localizes To The Endoplasmic Reticulum–Golgi Intermediate Compartment And To Cis-Golgi Cisternae, Lelio Orci, Mariella Ravazzola, Gary J. Mack, Charles Barlowe, Stefan Otte

Dartmouth Scholarship

Yeast endoplasmic reticulum (ER) vesicle protein Erv46p is a novel membrane protein involved in transport through the early secretory pathway. Investigation of mammalian Erv46 (mErv46) reveals that it is broadly expressed in tissues and protein-secreting cells. By immunofluorescence microscopy, mErv46 displays a crescent-shaped perinuclear staining pattern that is characteristic of the Golgi complex. Quantitative immunoelectron microscopy indicates that mErv46 is restricted to the cis face of the Golgi apparatus and to vesicular tubular structures between the transitional ER and cis-Golgi. Minor amounts of mErv46 reside in ER membranes and later Golgi cisternae. On Brefeldin A treatment, mErv46 redistributes to punctate …

Promoters Of The Murine Embryonic Β-Like Globin Genes Ey And Βh1 Do Not Compete For Interaction With The Β-Globin Locus Control Region, Xiao Hu, Michael Bulger, Julia N. Roach, Susan K. Eszterhas, Emmanuel Olivier, Eric Bouhassira, Mark Groudine, Steven Fiering

Dartmouth Scholarship

Mammalian β-globin loci contain multiple β-like genes that are expressed at different times during development. The murine β-globin locus contains two genes expressed during the embryo stage, Ey and βh1, and two genes expressed at both the fetal and postnatal stages, β-major and β-minor. Studies of transgenic human β-like globin loci in mice have suggested that expression of one gene at the locus will suppress expression of other genes at the locus. To test this hypothesis we produced mouse lines with deletions of either the Ey or βh1 promoter in the endogenous murine β-globin locus. Promoter deletion eliminated expression of …

Regulation Of Human Col9a1 Gene Expression. Activation Of The Proximal Promoter Region By Sox9., Ping Zhang, Sergio A. Jimenez, David G Stokes

Department of Medicine Faculty Papers

The COL9A1 gene contains two promoter regions, one driving expression of a long alpha1(IX) chain in cartilage (upstream) and one driving expression of a shorter chain in the cornea and vitreous (downstream). To determine how the chondrocyte-specific expression of the COL9A1 gene is regulated, we have begun to characterize the upstream chondrocyte-specific promoter region of the human COL9A1 gene. Transient-transfection analyses performed in rat chondrosarcoma (RCS) cells, human chondrosarcoma (HTB) cells, and NIH/3T3 cells showed that the COL9A1 promoter was active in RCS cells but not HTB or NIH/3T3 cells. Inclusion of the first intron had no effect on promoter …

Conjugated Linoleic Acid Does Not Improve Insulin Tolerance In Mice, Kimberly M Hargrave, Michael J. Azain, Stephen D. Kachman, Jess Miner

Department of Statistics: Faculty Publications

Objective: To determine if the addition or removal of dietary conjugated linoleic acid (CLA) would alter insulin tolerances in mice from two genetic lines.

Research Methods and Procedures: High metabolic rate (MH) and low metabolic rate (ML) mice were assigned to consume 1) a control diet ad libitum, 2) a control diet at a restricted intake, or 3) a diet containing 1% CLA ad libitum. After 9 weeks, an insulin tolerance test was conducted, and a portion of the mice were killed. All remaining mice consumed the control diet ad libitum. Insulin tolerance tests were conducted 11 and 32 days …

Exposure To Asphalt Fumes Activates Activator Protein-1 Through The Phosphatidylinositol 3-Kinase/Akt Signaling Pathway In Mouse Epidermal Cells, Cuiling Ma, Jin Wang, Jia Luo

Faculty & Staff Scholarship

No abstract provided.

Hydrogen Peroxide Formation And Actin Filament Reorganization By Cdc42 Are Essential For Ethanol-Induced In Vitro Angiogenesis, Yong Qian, Jia Luo, Stephen S. Leonard, Gabriel K. Harris, Lyndell Millecchia, Daniel C. Flynn, Xianglin Shi

Faculty & Staff Scholarship

No abstract provided.

A Genetic Lesion That Arrests Plasma Cell Homing To The Bone Marrow, Loren D. Erickson, Ling-Li Lin, Biyan Duan, Laurence Morel, Randolph J. Noelle

Dartmouth Scholarship

The coordinated regulation of chemokine responsiveness plays a critical role in the development of humoral immunity. After antigen challenge and B cell activation, the emerging plasma cells (PCs) undergo CXCL12-induced chemotaxis to the bone marrow, where they produce Ab and persist. Here we show that PCs, but not B cells or T cells from lupus-prone NZM mice, are deficient in CXCL12-induced migration. PC unresponsiveness to CXCL12 results in a marked accumulation of PCs in the spleen of mice, and a concordant decrease in bone marrow PCs. Unlike normal mice, in NZM mice, a majority of the splenic PCs are long-lived. …

Comparison Of Ifat And Elisa Results In Mice Experimentally Infected With Toxocara Canis, Hasan Ayçi̇çek, Mehmet Tanyüksel

Turkish Journal of Veterinary & Animal Sciences

Toxocariasis is a disease which indicates a wide symptomatic spectrum and occurs usually by the ingestion of infective Toxocara canis (rarely Toxocara cati) eggs by humans as a paratenic host. In this study, the sera samples of experimentally infected mice were evaluated on different days by IFAT and ELISA. Regarding the sera samples obtained on the 15^{th} and following days of the study, the groups seropositivity in IFAT by adult and larval sectional antigens and in TES-ELISA were 70, 73.3 and 96.7%, respectively. In the control group, seronegativity in IFAT by adult and larval sectional antigens, and in T. canis …

Rac-1 And Iqgap Are Potential Regulators Of E-Cadherin-Catenin Interactions During Murine Preimplantation Development., David R Natale, Andrew J Watson

Obstetrics & Gynaecology Publications

Adherens junction formation is fundamental for compaction and trophectoderm differentiation during mammalian preimplantation development. We recently isolated an IQGAP-2 cDNA from a differential display-polymerase chain reaction screen of bovine preimplantation developmental stages. IQGAP-1 and -2 proteins mediate E-cadherin-based cell-to-cell adhesion through interactions with beta-catenin and the Rho GTPases, rac1 and cdc42. Our study demonstrates IQGAP-1,-2, rac-1 and cdc42 mRNAs are present throughout murine preimplantation development. IQGAP-1 and rac-1 protein distribution changes from predominantly plasma membrane associated to predominantly cytoplasmic as the embryo progresses through cleavage divisions and compaction to the blastocyst stage.