Cell and Developmental Biology Commons^™

Mutations In Sid2, A Novel Gene In Saccharomyces Cerevisiae, Cause Synthetic Lethality With Sic1 Deletion And May Cause A Defect During S Phase, Matthew D. Jacobson , '97, Claudia C. Muñoz , '99, Kirstin S. Knox , '99, Beth E. Williams , '01, Lenette L. Lu , '02, Frederick Cross , '78, Elizabeth Ann Vallen

Biology Faculty Works

SIC1 encodes a nonessential B-type cyclin/CDK inhibitor that functions at the G1/S transition and the exit from mitosis. To understand more completely the regulation of these transitions, Mutations causing synthetic lethality with sic1 Delta were isolated. In this screen, we identified a novel gene, SID2, which encodes an essential protein that appear., to be required for DNA replication or repair. sid2-1 sic1 Delta strains and sid2-21 temperature-sensitive strains arrest preanaphase as large-budded cells with a single nucleus, a short spindle, and an similar to 2C DNA content. RAD9, which is necessary for the DNA damage checkpoint, is required for the …

The Wings Of Bombyx Mori Develop From Larval Discs Exhibiting An Early Differentiated State: A Preliminary Report, Madhuri Kango-Singh, Amit Singh, K. P. Gopinathan

Biology Faculty Publications

Lepidopteran insects present a complex organization of appendages which develop by various mechanisms. In the mulberry silkworm, Bombyx mori, a pair of meso- and meta-thoracic discs located on either side in the larvae gives rise to the corresponding fore- and hind-wings of the adult. These discs do not experience massive cell rearrangements during metamorphosis and display the adult wing vein pattern. We have analysed wing development in B. mori by two approaches, viz., expression of patterning genes in larval wing discs, and regulatory capacities of larval discs following explantation or perturbation. Expression of Nubbin is seen all over the presumptive …

Salivary Acinar Cells From Aquaporin 5-Deficient Mice Have Decreased Membrane Water Permeability And Altered Cell Volume Regulation, Carissa M. Krane, James E. Melvin, Ha-Van Nguyen, Linda Richardson, Jennifer E. Towne, Thomas Doetschman, Anil G. Menon

Biology Faculty Publications

Aquaporins (AQPs) are channel proteins that regulate the movement of water through the plasma membrane of secretory and absorptive cells in response to osmotic gradients. In the salivary gland, AQP5 is the major aquaporin expressed on the apical membrane of acinar cells. Previous studies have shown that the volume of saliva secreted by AQP5-deficient mice is decreased, indicating a role for AQP5 in saliva secretion; however, the mechanism by which AQP5 regulates water transport in salivary acinar cells remains to be determined. Here we show that the decreased salivary flow rate and increased tonicity of the saliva secreted byAqp5 …

Chromosome Movement In Mitosis Requires Microtubule Anchorage At Spindle Poles, Michael B. Gordon, Louisa Howard, Duane A. Compton

Dartmouth Scholarship

Anchorage of microtubule minus ends at spindle poles has been proposed to bear the load of poleward forces exerted by kinetochore-associated motors so that chromosomes move toward the poles rather than the poles toward the chromosomes. To test this hypothesis, we monitored chromosome movement during mitosis after perturbation of nuclear mitotic apparatus protein (NuMA) and the human homologue of the KIN C motor family (HSET), two noncentrosomal proteins involved in spindle pole organization in animal cells. Perturbation of NuMA alone disrupts spindle pole organization and delays anaphase onset, but does not alter the velocity of oscillatory chromosome movement in prometaphase. …

Analysis Of E. Coli Dna From Selected Source(S) Using Pulsed-Field Gel Electrophoresis, Sheema Doshi

Theses, Dissertations and Capstones

The presence of fecal coliforms in surface waters is a public health issue throughout the United States and Canada. The presence of Escherichia coli (E. coli) indicates recent fecal contamination from either animal or human sources. To solve this growing problem one must identify the source(s) of such contamination by creating a database of DNA profiles of£. coli isolates. Hence, tracking the source(s) of E. coli can help link water contamination to animal source(s) of contamination. In this study, pulsed field gel electrophoresis (PFGE) was used to analyze DNA from E. coli isolates from known animals. For PFGE, the bacterial …

Factors Influencing Spatial Variability In Soil Nitrogen (N) Dynamics In N-Treated And Untreated Watersheds Of The Fernow Experimental Forest, West Virginia, Nikki Lenore Lyttle

Theses, Dissertations and Capstones

The central Appalachian region of the United States receives some of the highest inputs of nitrogen (N) due to acidic deposition in the nation. It is believed that these high could levels contribute to a decline in forest soils within the next 50 to 70 yrs. This study examines factors that influence spatial variability in N-treated and untreated watersheds of the Fernow Experimental Forest, Parsons, West Virginia. Within each of the two watersheds [WS4 untreated control, > 100 yr.; WS3 N-treated, acidified, clear cut, ~ 31 yr.], two 0.04 ha plots, one high N and one low N, were selected for …

Characterization And Regulation Of Skn-Directed Autoimmune Skin Lesions, Pamela Jane Staton

Theses, Dissertations and Capstones

In the Skn model of autoimmunity, pathogenic T cells sensitized to Skn epidermal antigens (Skn-immune spleen cells or SIS cells) elicited disease in the form of skin lesions when adoptively transferred into shaved immunoincompetent syngeneic adult recipients (‘lesion-forming animals’) while concomitant injection of immunoregulatory normal spleen cells at twice the concentration (2 x normal spleen cells or 2XNS cells) of SIS cells significantly lessened lesion development (‘lesion-controlling animals’) by Day 7 post cell transfer. In a time-course RT-PCR cytokine analysis of skin from lesion-forming and lesion-controlling animals, IL-7 mRNA was significantly elevated in lesion-controlling skin on Day 7 while no …

Aquaporin 5-Deficient Mouse Lungs Are Hyperresponsive To Cholinergic Stimulation, Carissa M. Krane, Christopher N. Fortner, Arthur R. Hand, Dennis W. Mcgraw, John N. Lorenz, Susan E. Wert, Jennifer E. Towne, Richard J. Paul, Jeffrey A. Whitsett, Anil G. Menon

Biology Faculty Publications

Although aquaporin 5 (AQP5) is the major water channel expressed in alveolar type I cells in the lung, its actual role in the lung is a matter of considerable speculation. By using immunohistochemical staining, we show that AQP5 expression in mouse lung is not restricted to type I cells, but is also detected in alveolar type II cells, and in tracheal and bronchial epithelium. Aqp5 knockout (Aqp5−/−) mice were used to analyze AQP5 function in pulmonary physiology. Compared with Aqp5+/+ mice, Aqp5−/− mice show a significantly increased concentration-dependent bronchoconstriction to intravenously administered Ach, as shown by …

Hawaiian Freshwater Polychaeta: A Potentially Substantial Trophic Component Of Stream Depositional Habitats, M. Eric Benbow, Albert J. Burky, Carl M. Way

Biology Faculty Publications

In this paper we report the widespread occurrence of large annelids (Polychaeta: Nereididae) in Hawaiian stream depositional habitats, drawing attention to the lack of knowledge of Hawaiian stream energetics. Specimens of Namalycastis sp. were collected from five Hawaiian Islands from May–July 1995 and from the island of Maui from July–December 1999 and April–July 2000. Most specimens collected were N. hawaiiensis, while two specimens of N. abiuma were collected from a single site on the island of Molokai. Specimens were collected from elevations ranging from 3–240 m; several collections were from sites above at least one major (> 15 m …

Chondrocranium And Visceral Skeleton Of Atelopus Tricolor And Atelophryniscus Chrysophorus, E O. Lavilla, Rafael O. De Sá

Biology Faculty Publications

Atelopus tricolor and Atelophryniscus chrysophorus have gastromyzophorous tadpoles. Aside from specific differences, the larval chondrocrania and visceral skeletons show several shared character states, including an almost quadrangular, open chondrocranium , cornua trabeculae with expanded tips, cartilago suprarostralis as a single element, a posteriorly projected arcus subocularis quadrati, a closed muscular tunnel, and a simplified branchial basket, with only three pairs of ceratobranchiales. They are compared with diverse character states of suctorial larvae considering them as causally related to the stream life adaptations.

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

The timing and pattern of myogenesis varies among anurans that have been studied and the different pat- terns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., 1989) and they can provide infor- mation on evolutionary changes for closely related lineages within a clade. For example, we previously com- pared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick et al., 1999). We found that although the timing of myogenesis differed, …

Fast Transport Of Neurofilament Protein Along Microtubules In Squid Axoplasm, Veena Prahlad, Brian T. Helfand, George M. Langford, Ron D. Vale, Robert D. Goldman

Dartmouth Scholarship

Using squid axoplasm as a model system, we have visualized the fast transport of non-filamentous neurofilament protein particles along axonal microtubules. This transport occurs at speeds of 0.5-1.0 microm/second and the majority of neurofilament particles stain with kinesin antibody. These observations demonstrate, for the first time, that fast (0.5-1.0 microm/second) transport of neurofilament proteins occurs along microtubules. In addition, our studies suggest that neurofilament protein can be transported as non-membrane bound, nonfilamentous subunits along axons, and that the transport is kinesin-dependent. Microtubule-based fast transport might therefore provide a mechanism for the distribution and turnover of neurofilament, and perhaps other cytoskeletal …

The Occurrence Of The Freshwater Clams, Musculium Partumeium (Say) And Pisidium Casertanum (Poli) (Bivalvia: Sphaeriidae), In The Hawaiian Islands, Albert J. Burky, Carl M. Way, Skippy Hau, M. Eric Benbow

Biology Faculty Publications

Sphaeriid clams were collected from an ancient, continuously cultivated taro pond complex at Ke‘anae Peninsula, Maui. Both species are known for adaptations for temporary pond habitats and could have been initially introduced by the earliest Hawaiian settlers transported with moist taro root stock from other areas of Oceania.

Altered T Cell-Mediated Immunity And Infectious Factors In Autism, Yong Hu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three major questions were addressed in this dissertation: 1) Do immune abnormalities associated with autism primarily alter CD4+ T cell-mediated or humoral immune responses? 2) Are specific T cell clones expanded in autism? 3) Which, if any, infectious agents play a role in autism?

CD4+ T cell-mediated (Th1) or humoral (Th2) immune responses can be distinguished on the basis of the cytokines expressed. CD4+ T-cells secrete interleukin type 2 (IL-2) and interferon-γ, whereas a Th2 response is associated with secretion of interleukin type 4(IL-4). mRNA extracted from peripheral blood mononuclear nuclear cells (PBMC) showed significantly increased levels of IL-2 and …

The Docking Stage Of Yeast Vacuole Fusion Requires The Transfer Of Proteins From A Cis-Snare Complex To A Rab/Ypt Protein, Albert Price, Darren Seals, William Wickner, Christian Ungermann

Dartmouth Scholarship

The homotypic fusion of yeast vacuoles requires Sec18p (NSF)-driven priming to allow vacuole docking, but the mechanism that links priming and docking is unknown. We find that a large multisubunit protein called the Vam2/6p complex is bound to cis-paired SNAP receptors (SNAREs) on isolated vacuoles. This association of the Vam2/6p complex with the cis-SNARE complex is disrupted during priming. The Vam2/6p complex then binds to Ypt7p, a guanosine triphosphate binding protein of the Rab family, to initiate productive contact between vacuoles. Thus, cis-SNARE complexes can contain Rab/Ypt effectors, and these effectors can be mobilized by NSF/Sec18p-driven priming, allowing their direct …

Roles Of Hof1p, Bni1p, Bnr1p, And Myo1p In Cytokinesis In Saccharomyces Cerevisiae, Elizabeth Ann Vallen, J. Caviston, E. Bi

Biology Faculty Works

Cytokinesis in Saccharomyces cerevisiae occurs by the concerted action of the actomyosin system and septum formation. Here we report on the roles of HOF1,BNI1, and BNR1 in cytokinesis, focusing on Hof1p. Deletion of HOF1 causes a temperature-sensitive defect in septum formation. A Hof1p ring forms on the mother side of the bud neck in G2/M, followed by the formation of a daughter-side ring. Around telophase, Hof1p is phosphorylated and the double rings merge into a single ring that contracts slightly and may colocalize with the actomyosin structure. Upon septum formation, Hof1p splits into two rings, disappearing upon cell separation. Hof1p …

The Life History Of The Cave Salamander, Eurycea Lucifuga Rafinesque, In West Virginia, Andrew James Longenecker

Theses, Dissertations and Capstones

In West Virginia, as throughout its range, there is limited information about the life history of the cave salamander (Eurycea lucifuga). The purpose of this study was to describe the natural history of this species in West Virginia. The objectives of this study were to determine habitat selection of the cave salamander, to ascertain its environmental characteristics, and to study its reproductive and non-reproductive biology. Three study caves were located in Greenbrier County, West Virginia. All sites were examined at least once each month from May 1999 through April 2000. Caves were divided into three zones: entrance, twilight, …

Ecology And Sympatric Relations Of Crevice Salamanders In Randolph County, West Virginia, Jayme Linn Waldron

Theses, Dissertations and Capstones

By implementing a mark-recapture study, I investigated the ecology of three species of sympatric plethodontid salamanders (Aneides aeneus, Desmognathus ochrophaeus, and Plethodon glutinosus) on rock outcrops in the Westvaco Wildlife and Ecosystem Research Forest, Randolph County, West Virginia. By examining activity patterns, vertical stratification, and habitat preference for A. aeneus, D. ochrophaeus, and P. glutinosus, I attempted to offer some insight into how these sympatric species avoid competition on small, isolated rock outcrops. Twenty-one surveys, both nocturnal and diurnal, were performed between 11 May and 17 October, 1999. During this time, 89 salamanders, encompassing five species ( …

Whole Animal And Cellular Strategies In The Regulation Of Bone Mass In The Rat, Weidong Geng

Theses, Dissertations and Capstones

In order to determine the strategies in regulation of bone mass in the rat and better understand the pathophysiological mechanism of the postmenopausal osteoporosis, a series of studies were conducted at the whole animal and cellular level. At the whole animal level, female Sprague-Dawley rats were ovariectomized (Ovx) or sham-operated (control) at 18 weeks and the entire skeleton obtained at 24 weeks (baseline) or after an additional 31 day (28 week) interval on a normal (1.0%) or deficient (0.02%) calcium diet. Ovx rats on the normal calcium diet showed a 42% increase in whole body bone resorption and a 70% …

Mitochondrial 16s Rrna Gene As A Tool For Scorpion Systematics, Mark D. Barker

Theses, Dissertations and Capstones

The use of morphological analysis in the classification and phylogeny of scorpions often has led to confusion and controversy. In order to clarify these problems other character sets should be considered for analysis. One such tool is the use of molecular comparisons between organisms. This study used a section of the mitochondrial 16S ribosomal RNA gene. This technique was applied to investigate four scorpion genera belonging to three families: Hadruru, Anuroctonus (luridae), Euscorpius (Euscorpiidae), and Centruroides (Buthidae). Total DNA was extracted with a standard phenol/chloroform method; a gene of interest was amplified using PCR; and resulting DNA sequence analysis was …

The Kinesin-Related Protein, Hset, Opposes The Activity Of Eg5 And Cross-Links Microtubules In The Mammalian Mitotic Spindle, Vicki Mountain, Calvin Simerly, Louisa Howard, Asako Ando, Gerald Schatten, Duane A. Compton

Dartmouth Scholarship

We have prepared antibodies specific for HSET, the human homologue of the KAR3 family of minus end-directed motors. Immuno-EM with these antibodies indicates that HSET frequently localizes between microtubules within the mammalian metaphase spindle consistent with a microtubule cross-linking function. Microinjection experiments show that HSET activity is essential for meiotic spindle organization in murine oocytes and taxol-induced aster assembly in cultured cells. However, inhibition of HSET did not affect mitotic spindle architecture or function in cultured cells, indicating that centrosomes mask the role of HSET during mitosis. We also show that (acentrosomal) microtubule asters fail to assemble in vitro without …

Estructura Del Condrocráneo Y Esqueleto Visceral De Larvas De Pseudis Minuta (Anura, Pseudidae, E. O. Lavilla, Rafael O. De Sá

Biology Faculty Publications

The chondrocranium and visceral skeleton of Pseudis minuta tadpoles are described, based on a series of five larvae in stages 31 - 35 of Gosner (1960). Among their striking characters are the presence of peculiar articular surfaces between cornua trabeculae and suprarostral cartilage, the incomplete development of the orbital cartilage, the high fenestration of the floor of the cavum cranii, the fusion of posterior foramina, and the fusion of spicules 3 and 4 in the hyobranchial skeleton.

The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá

Biology Faculty Publications

Differences in the relative timing of homologous developmental events among closely related species, known as heterochronies, may provide valuable clues in understanding evolutionary relationships (McKinney, 1988; McNamara, 1995). Examining the timing of myogenic events is a relatively easy and effective method for finding heterochronic events. For example, whether muscle proteins and myofibrils appear before or after multinucleation can be determined through histological techniques (Kielbowna, 1981). Simple observations of live specimens can pinpoint functional landmarks such as first twitch (spontaneous or due to external stimuli) and first heartbeat.

Development Of The Suprarostral Plate Of Pipoid Frogs, Rafael O. De Sá, Charles C. Swart

Biology Faculty Publications

The rostral region of nonpipoid tadpoles has two sets of cartilages, the cornua trabeculae and the suprarostral cartilages, whereas the rostral region in pipoid larvae is occupied by a single and continuous cartilage, the suprarostral plate. The homology of this region in pipoid and nonpipoids tadpoles has been controversial. We examined the early formation and development of the suprarostral plate using serially cross-sectioned specimens of Rhinophrynus, Xenopus, and Hymenochirus. We conclude that the cartilaginous structures present in the rostral area of pipoid and nonpipoid larvae are homologous. Furthermore, we found two different developmental patterns among pipoid larvae. The chondrocranium …

Genetic Control Of Programmed Cell Death In The Caenorhabditis Elegans Hermaphrodite Germline, Tina Gumienny, Eric Lambie, Erika Hartwieg, H. Robert Horvitz, Michael Hengartner

Dartmouth Scholarship

Development of the nematode Caenorhabditis elegans is highly reproducible and the fate of every somatic cell has been reported. We describe here a previously uncharacterized cell fate in C. elegans: we show that germ cells, which in hermaphrodites can differentiate into sperm and oocytes, also undergo apoptotic cell death. In adult hermaphrodites, over 300 germ cells die, using the same apoptotic execution machinery (ced-3, ced-4 and ced-9) as the previously described 131 somatic cell deaths. However, this machinery is activated by a distinct pathway, as loss of egl-1 function, which inhibits somatic cell death, does not affect germ cell apoptosis. …

Osteological Analysis Of The Killifish Genus Cynolebias (Cyprinodontiformes: Rivulidae), Marcelo Loureiro, Rafael O. De Sá

Biology Faculty Publications

Relationships among the species of the annual fish Cynolebias are unclear. An analysis of the variation and utility of osteological characters for phylogenetic analysis was done using cleared and double-stained specimens representing 21 species of Cynolebias. This analysis showed that some of the characters previously used to diagnose this genus and some of the species are polymorphic. Osteologically, Cynolebias can be diagnosed by the following synapomorphies: (1) triangular-shaped parietal, (2) vomer positioned ventral to the parasphenoid, (3) long ventral process of the dentary, (4) teeth on fourth ceratobranchial, and (5) teeth on first epibranchial. In addition, characters that help …

The Role Of Retinoids And Protein Kinase C In Vascular Smooth Muscle Cell Proliferation And Function, Shaoshan Wang

Theses, Dissertations and Capstones

The structural and functional changes in the arterial wall of humans and animals accompany the development of hypertension and atherosclerosis. Hence, great interest exists in the mechanisms that govern vascular smooth muscle cell contraction and proliferation. Rat aortic rings maintained in organ culture show a significant loss of contractility; whereas, vascular smooth muscle cells in culture quickly dedifferentiate into a secretory phenotype with a marked capacity for proliferation. The addition of all-trans retinoic acid (RA) and retinol to the plasma-containing medium preserved the contractile response of cultured vessels. Removal of endothelium prior to culture abolished these effects. All-trans retinoic acid …

Clarification Of The Hybrid Origin Of Carex X Deamii Herm. (Cyperaceae) Based On Macro And Micro Morphological Characters, Paul B. Marcum

Theses, Dissertations and Capstones

The origin of Carex x deamii Herm. has been in question ever since it was named to science in 1938. Collections of the hybrid have always been associated with C. shortiana Dewey and either C. typhina Michx. or C. squarrosa L.. C. typhina and C. squarrosa are closely related taxa (Section Squarrosae) and often are morphologically similar. Because of this similarity, determining the correct parental species to the hybrid has been extremely difficult. It is known that the hybrid is sterile and only reproduces asexually. Pollen was analyzed to ascertain the viability of all four taxa. This study utilizes both …

Ion Transport Processes Of Crustacean Epithelial Cells, Gregory A. Ahearn, Jeff Duerr, Zhenpeng Zhuang, Richard J. Brown, Amy Aslamkhan, Deirdre A. Killebrew

Faculty Publications - Department of Biological & Molecular Science

Epithelial cells of the gut, antennal glands, integument, and gills of crustaceans regulate the movements of ions into and across these structures and thereby influence the concentrations of ions in the hemolymph. Specific transport proteins serving cations and anions are found on apical and basolateral cell membranes of epithelia in these tissues. In recent years, a considerable research effort has been directed at elucidating their physiological and molecular properties and relating these characteristics to the overall biology of the organisms. Efforts to describe ion transport in crustaceans have focused on the membrane transfer properties of Na1/H1 exchange, calcium uptake as …

Drosophila Fascin Mutants Are Rescued By Overexpression Of The Villin-Like Protein, Quail, Kelly Cant, Brenda A. Knowles, Shalina Mahajan-Miklos, Matthew Heintzelman, Lynn Cooley

Dartmouth Scholarship

Actin bundle assembly in specialized structures such as microvilli on intestinal epithelia and Drosophila bristles requires two actin bundling proteins. In these systems, the distinct biochemical properties and temporal localization of actin bundling proteins suggest that these proteins are not redundant. During Drosophila oogenesis, the formation of cytoplasmic actin bundles in nurse cells requires two actin bundling proteins, fascin encoded by the singed gene and a villin-like protein encoded by the quail gene. singed and quail mutations are fully recessive and each mutation disrupts nurse cell cytoplasmic actin bundle formation. We used P-element mediated germline transformation to overexpress quail in …