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Full-Text Articles in Life Sciences

Assembly Of Α4Β2 Nicotinic Acetylcholine Receptors Assessed With Functional Fluorescently Labeled Subunits: Effects Of Localization, Trafficking, And Nicotine-Induced Upregulation In Clonal Mammalian Cells And In Cultured Midbrain Neurons, Raad Nashmi, Mary E. Dickinson, Sheri Mckinney, Mark Jareb, Cesar Labarca, Scott E. Fraser E. Fraser, Henry A. Lester Dec 2003

Assembly Of Α4Β2 Nicotinic Acetylcholine Receptors Assessed With Functional Fluorescently Labeled Subunits: Effects Of Localization, Trafficking, And Nicotine-Induced Upregulation In Clonal Mammalian Cells And In Cultured Midbrain Neurons, Raad Nashmi, Mary E. Dickinson, Sheri Mckinney, Mark Jareb, Cesar Labarca, Scott E. Fraser E. Fraser, Henry A. Lester

Biology Faculty Publications

Fura-2 recording of Ca2+ influx was used to show that incubation in 1 μM nicotine (2–6d) upregulates several pharmacological components of acetylcholine (ACh) responses in ventral midbrain cultures, including a MLA-resistant, DHβE-sensitive component that presumably corresponds to α4β2 receptors. To study changes in α4β2 receptor levels and assembly during this upregulation, we incorporated yellow and cyan fluorescent proteins (YFPs and CFPs) into the α4 or β2 M3–M4 intracellular loops, and these subunits were coexpressed in human embryonic kidney (HEK) 293T cells and cultured ventral midbrain neurons. The fluorescent …


Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi Nov 2003

Initial State Of The Drosophila Eye Before Dorsoventral Specification Is Equivalent To Ventral, Amit Singh, Kwang-Wook Choi

Biology Faculty Publications

Dorsoventral (DV) patterning is crucial for eye development in invertebrates and higher animals. DV lineage restriction is the primary event in undifferentiated early eye primordia of Drosophila. InDrosophila eye disc, a dorsal-specific GATA family transcription factor pannier (pnr) controls Iroquois-Complex (Iro-C) genes to establish the dorsal eye fate whereas Lobe (L), which is involved in controlling a Notch ligand Serrate (Ser), is specifically required for ventral growth. However, fate of eye disc cells before the onset of dorsal expression of pnr and Iro-C is not known. We show that L/Ser …


Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand Oct 2003

Skeletal Myosin Heavy Chain Function In Cultured Lung Myofibroblasts, Nancy A. Rice, Leslie A. Leinwand

Biology Faculty Publications

Myofibroblasts are unique contractile cells with both muscle and nonmuscle properties. Typically myofibroblasts are identified by the expression of smooth muscle actin (ASMA); however some myofibroblasts also express sarcomeric proteins. In this study, we show that pulmonary myofibroblasts express three of the eight known sarcomeric myosin heavy chains (MyHCs) (IIa, IId, and embryonic) and that skeletal muscle myosin enzymatic activity is required for pulmonary myofibroblast contractility. Furthermore, inhibition of skeletal myosin activity and myofibroblast contraction results in a decrease in both ASMA and skeletal MyHC promoter activity and ASMA protein expression, suggesting a potential coupling of skeletal myosin activity and …


The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif Oct 2003

The Biology Of Canadian Weeds. 126. Amaranthus Albus L., A. Blitoides S. Watson And A. Blitum L., Mihai Costea, François J. Tardif

Biology Faculty Publications

A review of biological information is provided for three species of the genus Amaranthus: A. albus L., A. blitoides S. Watson and A. blitum L. The last species has been revised taxonomically and a new subspecies for Canada is presented—A. blitum subsp. emarginatus (Moq. ex Uline & Bray) Carretero, Munoz Garmendia & Pedrol. Amaranthus albus and A. blitoides are native to the U.S.A. and introduced to Canada. Both species are annual ruderal and agrestal weeds. During the past 100 yr the two species have spread across most provinces of Canada, but the greatest frequency and abundance have been …


Rapping To Review: A Novel Strategy To Engage Students And Summarize Course Material, Maureen T. Knabb Sep 2003

Rapping To Review: A Novel Strategy To Engage Students And Summarize Course Material, Maureen T. Knabb

Biology Faculty Publications

No abstract provided.


Repairing The Sickle Cell Mutation. Ii. Effect Of Psoralen Linker Length On Specificity Of Formation And Yield Of Third Strand-Directed Photoproducts With The Mutant Target Sequence, Olga Amosova, Steven Broitman, Jacques R. Fresco Aug 2003

Repairing The Sickle Cell Mutation. Ii. Effect Of Psoralen Linker Length On Specificity Of Formation And Yield Of Third Strand-Directed Photoproducts With The Mutant Target Sequence, Olga Amosova, Steven Broitman, Jacques R. Fresco

Biology Faculty Publications

Three identical deoxyoligonucleotide third strands with a 3'-terminal psoralen moiety attached by linkers that differ in length (N=16, 6 and 4 atoms) and structure were examined for their ability to form triplex-directed psoralen photoproducts with both the mutant T residue of the Sickle Cell beta-globin gene and the comparable wild-type sequence in linear duplex targets. Specificity and yield of UVA (365 nm) and visible (419 nm) light-induced photoadducts were studied. The total photoproduct yield varies with the linker and includes both monoadducts and crosslinks at various available pyrimidine sites. The specificity of photoadduct formation at the desired mutant T residue …


Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson Jul 2003

Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

Brood size is often constrained by the amount of energy available to produce offspring. Yet, energetic constraints may not be as important if the physical capacity to brood offspring is limited. Investigating the relative importance of energetic and physical constraints on brood size is necessary to understand how reproductive strategies are molded by natural selection. We investigated how food availability affects brood size in Sphaerium striatinum, a freshwater bivalve. We reared juveniles to adulthood under three food levels in a common garden experiment. The number of reproductive attempts, brood size, and stage of offspring development were measured. Clams reared …


Life Cycle Of A Torrenticolous Hawaiian Chironomid (Telmatogeton Torrenticola): Stream Flow And Microhabitat Effects, M. Eric Benbow, Albert J. Burky, Carl M. Way Jun 2003

Life Cycle Of A Torrenticolous Hawaiian Chironomid (Telmatogeton Torrenticola): Stream Flow And Microhabitat Effects, M. Eric Benbow, Albert J. Burky, Carl M. Way

Biology Faculty Publications

In this study we documented the instar densities and life cycle of Telmatogeton torrenticola Terry (Chironomidae : Telmatogetoninae) from Kinihapai Stream, Maui, Hawaii. Greatest larval densities of this midge are found on substrates of high velocity, shallow flows of cascades, and splash zones of waterfalls, with lower densities in riffles. In the summer of 1994 we compared the effects of two microhabitats (termed optimal and suboptimal) on inter-instar density and relative abundance. In a second year (1995), we evaluated the effect of long-term reduced stream flow on these variables only in optimal microhabitats. A significant reduction in stream flow from …


Is Hp1 An Rna Detector That Functions Both In Repression And Activation?, Rebecca Kellum May 2003

Is Hp1 An Rna Detector That Functions Both In Repression And Activation?, Rebecca Kellum

Biology Faculty Publications

Heterochromatin is defined as regions of compact chromatin that persist throughout the cell cycle (Heitz, 1928). The earliest cytological observations of heterochromatin were followed by ribonucleotide labeling experiments that showed it to be transcriptionally inert relative to the more typical euchromatic regions that decondense during interphase. Genetic studies of rearrangements that place euchromatic genes next to blocks of heterochromatin also pointed out the repressive nature of heterochromatin (Grigliatti, 1991; and references therein). The discovery of the heterochromatin-enriched protein heterochromatin protein 1 (HP1) by Elgin and co-workers in the mid-1980s suggested that the distinct cytological features of this chromatin may be …


Blackwell Publishing Ltd. Chondrocranial, Hyobranchial And Internal Oral Morphology In Larvae Of The Basal Bufonid Genus Melanophryniscus (Amphibia: Anura), Peter M. Larson, Rafael O. De Sá, Diego Arrieta Apr 2003

Blackwell Publishing Ltd. Chondrocranial, Hyobranchial And Internal Oral Morphology In Larvae Of The Basal Bufonid Genus Melanophryniscus (Amphibia: Anura), Peter M. Larson, Rafael O. De Sá, Diego Arrieta

Biology Faculty Publications

Melanophryniscus is a genus of small toads inhabiting the southern portion of South America. This genus is considered basal within the family Bufonidae. Data on larval chondrocranial morphology do not exist for the genus and larval internal oral anatomy has only been described for a single species. Here, we describe chondrocranial and internal oral morphology in Melanophryniscus montevidensis, M. orejasmirandai and M. sanmartini. Chondrocranial morphology is similar among the species examined. Comparisons with other bufonids and with outgroup taxa suggest that the following chondrocranial characters may represent synapomorphies for the Bufonidae: free (or absent) ceratobranchial IV, a reduced …


The Tadpole Of Phrynobatrachus Mababiensis Fitzsimons, 1932 (Anura, Ranidae, Petropedetinae), Rafael O. De Sá, Alan Channing Jan 2003

The Tadpole Of Phrynobatrachus Mababiensis Fitzsimons, 1932 (Anura, Ranidae, Petropedetinae), Rafael O. De Sá, Alan Channing

Biology Faculty Publications

The puddle frog genus Phrynobatrachus Günther, 1862 comprises about 64 currently recognized species (Frost, 1985). Of these, only the tadpoles of P. natalensis (Smith, 1849) (Power, 1927; Channing, 2001), P. guineensis Guibé & Lamotte, 1961(Rödel,1998) and P. alticola Guibé & Lamotte, 1961 (Rödel & Ernst, 2002) have been described. Phrynobatrachus mababiensis FitzSimons, 1932 (Dwarf Puddle frog, Wager, 1986; Mababe River frog, Frank & Ramus, 1996) is a small frog that usually calls from low in thick vegetation on flooded terrains close to the water. Very little has been published about the biology of this species. Passmore & Carruthers (1979) reported …


Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá Jan 2003

Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus mystacinus are of moderate size, the head is as wide as long, and the hind limbs are moderately short (see Table; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally or at best are weakly expanded laterally and slightly darker than female throats. Male snouts are more spatulate than those of females. Male forearms are not hypertrophied. Males lack asperities on the thumbs and chest. One or two pairs of dorsolateral folds (indicated by dark/light outlining in indifferently preserved specimens) are present: one …


Polystomatidae (Monogenea) Of Southern African Anura: Eupolystoma Vanasi N. Sp. Parasitic In Schismaderma Carens (Smith), Louis H. Du Preez, Richard C. Tinsley, Rafael O. De Sá Jan 2003

Polystomatidae (Monogenea) Of Southern African Anura: Eupolystoma Vanasi N. Sp. Parasitic In Schismaderma Carens (Smith), Louis H. Du Preez, Richard C. Tinsley, Rafael O. De Sá

Biology Faculty Publications

Eupolystoma vanasi is described as a new species of the Polystomatidae parasitic in the urinary bladder of Schismaderma carens in Northern Province and KwaZulu-Natal Province, South Africa. This is the third Eupolystoma species described from Africa and the first polystomatid from Schismaderma, an anuran genus that is primitive with respect to the other African bufonids in which Eupolystoma has been recorded. The species is distinguished by body size (this is the largest Eupolystoma known; mean length of adults 6 mm), by genital spine number (4 in comparison with 6-9 in other species), marginal hooklet length (greater than in other …


Effect Of Water Removal On Introduced Caddisflies From A Tropical Mountain Stream, Mollie D. Mcintosh, Mark Eric Benbow, Albert J. Burky Jan 2003

Effect Of Water Removal On Introduced Caddisflies From A Tropical Mountain Stream, Mollie D. Mcintosh, Mark Eric Benbow, Albert J. Burky

Biology Faculty Publications

Tropical island streams worldwide are being threatened by existing or proposed dams and diversions. Numerous streams of the Hawaiian Islands have diversions that remove freshwater for human use; however, little research has addressed diversion effects on aquatic insect communities in tropical streams. We studied the effect of water removal by a stream diversion on density and biomass of two introduced Trichoptera, Cheumatopsyche analis (Banks) (Hydropsychidae) and Hydroptila potosina (Buenoa- Soria) (Hydroptilidae), in Iao Stream, Maui, Hawaii, from April-August 2000. Both species seem to have multivoltine life cycles. Pooled Trichoptera (both species) biomass was significantly greater above the diversion (178.3 mg.m-2 …


Life Cycle Of A Torrenticolous Hawaiian Chironomid (Telmatogeton Torrenticola): Stream Flow And Microhabitat Effects, Mark Eric Benbow, Albert J. Burky, C. M. Way Jan 2003

Life Cycle Of A Torrenticolous Hawaiian Chironomid (Telmatogeton Torrenticola): Stream Flow And Microhabitat Effects, Mark Eric Benbow, Albert J. Burky, C. M. Way

Biology Faculty Publications

In this study we documented the instar densities and life cycle of Telmatogeton torrenticola Terry (Chironomidae : Telmatogetoninae) from Kinihapai Stream, Maui, Hawaii. Greatest larval densities of this midge are found on substrates of high velocity, shallow flows of cascades, and splash zones of waterfalls, with lower densities in riffles. In the summer of 1994 we compared the effects of two microhabitats (termed optimal and suboptimal) on inter-instar density and relative abundance. In a second year (1995), we evaluated the effect of long-term reduced stream flow on these variables only in optimal microhabitats. A significant reduction in stream flow from …


Effects Of Range Size On Species–Area Relationships, Andrew P. Allen, Ethan P. White Jan 2003

Effects Of Range Size On Species–Area Relationships, Andrew P. Allen, Ethan P. White

Biology Faculty Publications

It has been known for some time that the slope of the species–area relationship increases asymptotically at broad spatial scales when richness is plotted against area on logarithmic axes. At continental to global scales, species–area relationships are determined to a large extent by the abundance and size distribution of species ranges. Here we present an analytical model that explicitly quantifies the effects of range size on species–area relationships. The model shows how range size and plot area interact to control the form of species–area relationships at broad spatial scales. It also demonstrates how changes in spatial scale affect biodiversity patterns …


Ethanol: A Better Preservation Technique For Daphnia, A. Ross Black, Stanley I. Dodson Jan 2003

Ethanol: A Better Preservation Technique For Daphnia, A. Ross Black, Stanley I. Dodson

Biology Faculty Publications

A 4% formalin-40% sucrose solution has been used by limnologists for three decades as the preferred freshwater zooplankton preservative because it kills and fixes cladocera (Branchiopoda) with relatively little distortion. Because of the increasing evidence of health hazards related to formalin, we sought an alternative, safer preservative that satisfies the need for low distortion. Our results suggest the ethanol preservative methods (70% and 95% treatments) are as good or better as using 4% sugar formalin to fix and store samples. Our results indicate the best method is to fix samples in 95% EtOH followed by storage in 70% EtOH. This …


Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger Jan 2003

Review Of The Nature Of Nebraska: Ecology And Biodiversity Paul A. Johnsgard, L. Lareesa Wolfenbarger

Biology Faculty Publications

As a newcomer to Nebraska and someone learning the natural history of this place, I thoroughly enjoyed The Nature of Nebraska. More consequentially, the book will serve as a valuable resource for longtime naturalists, teachers, and others who want to learn about Nebraska's natural history.

Opening with a discussion of geology and ecology, Johnsgard offers a broad overview of Nebraska's ecological diversity, intertwining material on the natural forces that have historically dominated the Plains with a discussion of the anthropogenic forces currently altering the region's unique ecological nature. Approximately half of the book is devoted to more specific descriptions …


Effects Of Social Interaction On The Electric Organ Discharge In A Mormyrid Fish, Gnathonemus Petersii (Mormyridae, Teleostei), Thomas A. Terleph, Peter Moller Jan 2003

Effects Of Social Interaction On The Electric Organ Discharge In A Mormyrid Fish, Gnathonemus Petersii (Mormyridae, Teleostei), Thomas A. Terleph, Peter Moller

Biology Faculty Publications

African weakly discharging electric fish (Mormyridae) use their self-generated electric signals and electroreceptive abilities for orientation and communication in the context of courtship and territorial interactions. This paper documents socially mediated changes in the electric organ discharge (EOD) of subadult Gnathonemus petersii under non-breeding environmental conditions. Increases in EOD duration and changes in the relative phase amplitudes occurred in dominant fish during same-sex (male–male, female–female) and opposite-sex interactions. Similar changes were also observed in fish that were restricted in their physical interactions, suggesting that direct contact is not necessary to induce dominance-typical EOD waveforms. The possible communicative functions of these …


Regulation Of Zebrafish Hindbrain Development By Fibroblast Growth Factor And Retinoic Acid: A Dissertation, Nicole M. Roy Jan 2003

Regulation Of Zebrafish Hindbrain Development By Fibroblast Growth Factor And Retinoic Acid: A Dissertation, Nicole M. Roy

Biology Faculty Publications

A thesis submitted to the Department of Biochemistry and Molecular Pharmacology and the Graduate School of Biomedical Sciences of the University of Massachusetts, Worcester in partial fulfilment of the requirements for the degree of Doctor of Philosophy, Biochemistry and Molecular Pharmacology.

Fibroblast growth factor (Fgf) and Retinoic acid (RA) are known to be involved in patterning the posterior embryo. Work has shown that Fgf can convert anterior tissue into posterior fates and that embryos deficient in Fgf signaling lack posterior trunk and tail structures. Likewise, studies performed on RA have shown that overexpression of RA posteriorizes anterior tissue, while disrupting …


Complete Nucleotide Sequence Of The Chloroplast Genome From A Leptosporangiate Fer, Adiantum Capillus-Veneris L., Paul G. Wolf, C. A. Rowe, R. B. Sinclair, M. Hasebe Jan 2003

Complete Nucleotide Sequence Of The Chloroplast Genome From A Leptosporangiate Fer, Adiantum Capillus-Veneris L., Paul G. Wolf, C. A. Rowe, R. B. Sinclair, M. Hasebe

Biology Faculty Publications

We determined the complete nucleotide sequence of the chloroplast genome of the leptosporangiate fern, Adiantum capillus-veneris L. (Pteridaceae). The circular genome is 150,568 bp, with a large single-copy region (LSC) of 82,282 bp, a small-single copy region (SSC) of 21,392 bp and inverted repeats (IR) of 23,447 bp each. We compared the sequence to other published chloroplast genomes to infer the location of putative genes. When the IR is considered only once, we assigned 118 genes, of which 85 encode proteins, 29 encode tRNAs and 4 encode rRNAs. Four protein-coding genes, all four rRNA genes and six tRNA genes occur …


Body Mass Of Late Quaternary Mammals, F. A. Smith, S. K. Lyons, S.K. Morgan Ernest, K. E. Jones, D. M. Kaufman, T. Dayan, P. A. Marquet, J. P. Haskell Jan 2003

Body Mass Of Late Quaternary Mammals, F. A. Smith, S. K. Lyons, S.K. Morgan Ernest, K. E. Jones, D. M. Kaufman, T. Dayan, P. A. Marquet, J. P. Haskell

Biology Faculty Publications

The purpose of this data set was to compile body mass information for all mammals on Earth so that we could investigate the patterns of body mass seen across geographic and taxonomic space and evolutionary time. We were interested in the heritability of body size across taxonomic groups (How conserved is body mass within a genus, family, and order?), in the overall pattern of body mass across continents (Do the moments and other descriptive statistics remain the same across geographic space?), and over evolutionary time (How quickly did body mass patterns iterate on the patterns seen today? Were the Pleistocene …


Improving Quantitative Understanding Using Spreadsheet Models, Michelle A. Baker Jan 2003

Improving Quantitative Understanding Using Spreadsheet Models, Michelle A. Baker

Biology Faculty Publications

No abstract provided.


Life History Characteristics Of Placental Nonvolant Mammals, S.K. Morgan Ernest Jan 2003

Life History Characteristics Of Placental Nonvolant Mammals, S.K. Morgan Ernest

Biology Faculty Publications

The purpose of this data set was to compile general life history characteristics for a variety of mammalian species in order to perform comparative life history analyses among different taxa and different body size groups. Data were collected from the literature, and data sources are documented for each species within the data file. Since life history characteristics will show minor variation with environmental conditions (resource availability, climate, competitive environment, and predation pressure) a general life history for each species was sought to average over minor differences in local populations. To create a general life history for each species, life history …