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1999

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Articles 1 - 30 of 269

Full-Text Articles in Biology

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan Bond, John Stephens, Daniel Pondella, James Allen, Mark Helvey May 2013

A Method For Estimating Marine Habitat Values Based On Fish Guilds, With Comparisons Between Sites In The Southern California Bight, Alan Bond, John Stephens, Daniel Pondella, James Allen, Mark Helvey

Alan B. Bond

Habitat valuation is an essential tool for tracking changes in habitat quality and in adjudicating environmental mitigation. All current methods for estimating habitat values of coastal marine sites rely heavily on the opinion of experts or on data variables that can readily be manipulated to influence the outcome. As a result, unbiased, quantitative comparisons between the values of different marine habitats are generally unavailable. We report here on a robust, objective technique for the valuation of marine habitats that makes use of data that are commonly gathered in surveys of marine fish populations: density, fidelity, and mean size. To insure …


Structure And Function Analysis Of Lin-14, A Temporal Regulator Of Postembryonic Developmental Events In Caenorhabditis Elegans, Yang Hong, Rosalind C. Lee, Victor Ambros Dec 1999

Structure And Function Analysis Of Lin-14, A Temporal Regulator Of Postembryonic Developmental Events In Caenorhabditis Elegans, Yang Hong, Rosalind C. Lee, Victor Ambros

Dartmouth Scholarship

During postembryonic development of Caenorhabditis elegans, the heterochronic gene lin-14 controls the timing of developmental events in diverse cell types. Three alternativelin-14 transcripts are predicted to encode isoforms of a novel nuclear protein that differ in their amino-terminal domains. In this paper, we report that the alternative amino-terminal domains of LIN-14 are dispensable and that a carboxy-terminal region within exons 9 to 13 is necessary and sufficient for in vivo LIN-14 function. A transgene capable of expressing only one of the three alternativelin-14 gene products rescues a lin-14 null mutation and is developmentally regulated by lin-4. …


The Return Of The Wild, John Jahoda Dec 1999

The Return Of The Wild, John Jahoda

Bridgewater Review

No abstract provided.


Abalone Aquaculture In Western Australia : Policy Guideline., Fisheries Western Australia. Dec 1999

Abalone Aquaculture In Western Australia : Policy Guideline., Fisheries Western Australia.

Fisheries management papers

Experimental or commercial abalone aquaculture is being pursued in many countries with major investments in The United States, Taiwan, China and Korea as well as in Australia. The combined total abalone aquaculture production from China and Taiwan was reported to be in the order of 2,000 tonnes and continues to rise. As cultured ‘cocktail’ abalone are below the legal harvest size of wild abalone, there will be limited competition between aquaculture and the wild fisheries.


Photoperiodic And Pineal Modification Of The Effect Of 6-Methoxybenzoxazolinone On Deciduoma Growth In Rats, Everett S. Nixon Dec 1999

Photoperiodic And Pineal Modification Of The Effect Of 6-Methoxybenzoxazolinone On Deciduoma Growth In Rats, Everett S. Nixon

Electronic Dissertations and Theses

The compound 6-methoxybenzoxazolinone (6-MBOA) is a nonestrogenic compound that enhances reproduction. Decidualization, marked by the decidual cell reaction, is a process that causes the transformation of the uterine stromal cells into decidual cells. The purpose of the study was to determine the reproductive role of 6-MBOA during decidualization in rats exposed to a short photoperiod (8L: 16D), and a long photoperiod (16L: 8D). Decidualization was induced by surgical uterine scratch trauma unto the anti-mesometrial surface of the uterine epithelium on day 4 of pseudopregnancy (PPG) a reproductive state that precedes and converges into decidualization. Rats were treated with subcutaneous doses …


A Comparison Of Hsp70 Expression And Thermotolerance In Adults And Larvae Of Three Drosophila Species, Robert A. Krebs Dec 1999

A Comparison Of Hsp70 Expression And Thermotolerance In Adults And Larvae Of Three Drosophila Species, Robert A. Krebs

Biological, Geological, and Environmental Faculty Publications

Heat shock proteins (Hsps) and other molecular chaperones perform diverse physiological roles. One is to facilitate, in part, organismal thermotolerance, of which the functional consequences depend on Hsp70 concentration and developmental stage in Drosophila melanogaster. To test whether an Hsp70-thermotolerance relationship is a general phenomenon within Drosophila, I assayed Hsp70 concentration at a range of temperatures in intact larvae and adults of three species, D. melanogaster, D. simulans, and D. mojavensis, and compared those results to the increase in survival to heat shock that occurs after an Hsp70 inducing pretreatment. Larvae of D. melanogaster and D. simulans responded similarly to …


Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane Dec 1999

Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …


Molecular Evidence For A New Bacteriophage Of Borrelia Burgdorferi, Christian H. Eggers, D. Scott Samuels Dec 1999

Molecular Evidence For A New Bacteriophage Of Borrelia Burgdorferi, Christian H. Eggers, D. Scott Samuels

Biological Sciences Faculty Publications

We have recovered a DNase-protected, chloroform-resistant molecule of DNA from the cell-free supernatant of a Borrelia burgdorferi culture. The DNA is a 32-kb double-stranded linear molecule that is derived from the 32-kb circular plasmids (cp32s) of the B. burgdorferi genome. Electron microscopy of samples from which the 32-kb DNA molecule was purified revealed bacteriophage particles. The bacteriophage has a polyhedral head with a diameter of 55 nm and appears to have a simple 100-nm-long tail. The phage is produced constitutively at low levels from growing cultures of some B. burgdorferi strains and is inducible to higher levels with 10 mu …


Survey Of Amphibians And Reptiles In Powhatan County, Virginia With Selected Natural History Notes, Jason Daniel Gibson Dec 1999

Survey Of Amphibians And Reptiles In Powhatan County, Virginia With Selected Natural History Notes, Jason Daniel Gibson

Theses & Honors Papers

This thesis establishes baseline data on the herpetofauna that exist in Powhatan county. No systematic study of the amphibians and reptiles in Powhatan county has ever been conducted. The methods used in this survey include hand capture, egg mass observations, road kill collections, and frog call surveys. Documentation of each species collected included measurements, photographs, range maps, and tape recordings.

This survey produced 8 species of salamanders, 11 anurans, 6 turtles, 4 lizards, and 14 snakes. Based on records in the Atlas of Amphibians and Reptiles of Virginia (Mitchell & Reay, 1999), 11 new county records were discovered. This brings …


Phylogeography Of The Night Lizard, Xantusia Henshawi, From Southern California, Robert Edward Lovich Dec 1999

Phylogeography Of The Night Lizard, Xantusia Henshawi, From Southern California, Robert Edward Lovich

Loma Linda University Electronic Theses, Dissertations & Projects

The granite night lizard, Xantusia henshawi, is a highly specialized crevice dwelling lizard found in the Peninsular Ranges of southern California, United States and northern Baja California, Mexico. Generally, little morphological variation is seen in this species over a variety of habitats throughout its range, from elevations near sea level to approximately 2000 meters, and from Mediterranean habitats near the Pacific coast to arid desert habitat in the Colorado Desert of California. One exception is the variation seen in the subspecies X h. gracilis, which differs from X h. henshawi in morphology, allozymes, ecology, and natural history.

In …


Use Of Randomly Amplified Polymorphic Dna-Polymerase Chain Reaction (Rapd-Pcr) To Distinguish North American Populations Of Acroptilon Repens (L.) Dc, Raul A. Ruiz Dec 1999

Use Of Randomly Amplified Polymorphic Dna-Polymerase Chain Reaction (Rapd-Pcr) To Distinguish North American Populations Of Acroptilon Repens (L.) Dc, Raul A. Ruiz

Theses and Dissertations - UTB/UTPA

Sixty U.S. populations of Acroptilon repens collected in 1998 were analyzed using RAPD-PCR. Each population was represented by five specimens gathered from each location. A total of 301 specimens were examined using two Operon Technologies, RAPD-PCR primers (A 10 and C04). The DNA amplification products produced through the PCR process were electrophoretically separated to produce DNA fragments ranging from 100 to 2000 base-pairs in length. The 60 U.S. populations sampled, produce ten RAPD banding pattern types using A 10 primer and seventeen pattern types with C04. Genetic variation within and among the populations was low, however, one dendogram did show …


Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel Dec 1999

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Department of Biology Faculty Publications

The January tetra (Hemigrammus hyanuary Durbin) exhibits two eye color phenotypes. These have a silver iris, which is characteristic of the species, and a green color variant. Segregation patterns observed in the progenies from 12 different crosses support an hypothesis for the monogenic inheritance of iris coloration in this species.


Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel Nov 1999

Monogenic Control Of Iris Coloration In The January Tetra (Hemigrammus Hyanuary Characidae), Jack Frankel

Jack Frankel

The January tetra (Hemigrammus hyanuary Durbin) exhibits two eye color phenotypes. These have a silver iris, which is characteristic of the species, and a green color variant. Segregation patterns observed in the progenies from 12 different crosses support an hypothesis for the monogenic inheritance of iris coloration in this species.


Three-Dimensional Structure Of A Complex Between The Death Domains Of Pelle And Tube, Tsan Xiao, Par Towb, Steven A. Wasserman, Stephen R. Sprang Nov 1999

Three-Dimensional Structure Of A Complex Between The Death Domains Of Pelle And Tube, Tsan Xiao, Par Towb, Steven A. Wasserman, Stephen R. Sprang

Biological Sciences Faculty Publications

The interaction of the serine/threonine kinase Pelle and adaptor protein Tube through their N-terminal death domains leads to the nuclear translocation of the transcription factor Dorsal and activation of zygotic patterning genes during Drosophila embryogenesis. Crystal structure of the Pelle and Tube death domain heterodimer reveals that the two death domains adopt a six-helix bundle fold and are arranged in an open-ended linear array with plastic interfaces mediating their interactions. The Tube death domain has an insertion between helices 2 and 3, and a C-terminal tail making significant and indispensable contacts in the heterodimer. In vivo assays of Pelle and …


Factors Affecting Growth And Survival Of Snowy Egret Nestlings, Lisa Borgia Nov 1999

Factors Affecting Growth And Survival Of Snowy Egret Nestlings, Lisa Borgia

FIU Electronic Theses and Dissertations

It is widely believed that wading birds in the Everglades have declined as a result of historic water management practices. I determined growth rates for Snowy Egret (Egretta thula) chicks by assessed the nestling body condition through measurement of body weight and skeletal traits. A growth index was calculated as a residual of body weight regressed on age. A body condition index was calculated as the residual of body weight regressed on a skeletal trait (tarsus). Growth was significantly related to water level and hatch date. Survival rates were calculated to day 14, 21, and 50. Survival to …


The Rodent Fauna Of Long Pine Key, Everglades National Park: A Comparison Of Habitat Types, Carlos J. Calandriello Nov 1999

The Rodent Fauna Of Long Pine Key, Everglades National Park: A Comparison Of Habitat Types, Carlos J. Calandriello

FIU Electronic Theses and Dissertations

Rodents are often involved at several stages of trophic dynamics. Consequently they often play crucial roles in the structure and function of many complex ecological systems. This study sought to address the lack of baseline data concerning rodents in tropical areas, and south Florida in particular. Live trapping took place in the four major habitat types of the Long Pine Key area of Everglades National Park over the course of one year. I compared population structures and abundance of murid rodents in the four habitat types, and tested multiple weather variables for their effectiveness as predictors of rodent abundance. I …


Nutrient Cycling In The Water Column Of A Subtropical Seagrass Meadow, Susan Ziegler, Ronald Benner Nov 1999

Nutrient Cycling In The Water Column Of A Subtropical Seagrass Meadow, Susan Ziegler, Ronald Benner

Faculty Publications

The cycling of nutrients was studied over a 16 mo period to determine how processes occurring between the water column and benthos influenced nutrient dynamics in a Thalassia testudinum dominated seagrass meadow. Nutrient concentrations were low and ranged from below detection to 0.59 µM ammonium (NH4+), 0.04 to 0.29 µM nitrate plus nitrite (NO3- + NO2-), and below detection to 0.22 µM soluble reactive phosphate (SRP). Water column and benthic fluxes of NO3- + NO2- and SRP were usually below detection. The benthic fluxes of NH4+ …


Evolutionary And Acclimation-Induced Variation In The Heat-Shock Responses Of Congeneric Marine Snails (Genus Tegula) From Different Thermal Habitats: Implications For Limits Of Thermotolerance And Biogeography, Lars Tomanek, George N. Somero Nov 1999

Evolutionary And Acclimation-Induced Variation In The Heat-Shock Responses Of Congeneric Marine Snails (Genus Tegula) From Different Thermal Habitats: Implications For Limits Of Thermotolerance And Biogeography, Lars Tomanek, George N. Somero

Biological Sciences

Heat stress sufficient to cause cellular damage triggers the heat-shock response, the enhanced expression of a group of molecular chaperones called heat-shock proteins (hsps). We compared the heat-shock responses of four species of marine snails of the genus Tegula that occupy thermal niches differing in absolute temperature and range of temperature. We examined the effects of short-term heat stress and thermal acclimation on the synthesis of hsps of size classes 90, 77, 70 and 38 kDa by measuring incorporation of (35)S-labeled methionine and cysteine into newly synthesized proteins in gill tissue. Temperatures at which enhanced synthesis of hsps first occurred …


The Edaphic Factor And Patterns Of Variation In Lasthenia Californica (Asteraceae), Nishanta Rajakaruna, Bruce A. Bohm Nov 1999

The Edaphic Factor And Patterns Of Variation In Lasthenia Californica (Asteraceae), Nishanta Rajakaruna, Bruce A. Bohm

Biological Sciences

Transectional studies of Lasthenia californica in the Jasper Ridge Biological Preserve (Stanford University) have documented the existence of two races (A and C) based upon flavonoid chemistry, achene morphology, allozymes, and flowering time differences. The two races coexist on a serpentine outcrop and have maintained a sharply defined pattern of distribution for a period of at least 15 yr. The present study has revealed significant differences in the physical and chemical features of the soils harboring the two races. Soils at the lower ends of the transects, where race A plants grow, have higher pH, cation exchange capacity, relative water …


Analysis Of Age And Growth In Two Eastern Pacific Groupers (Serranidae: Epinephelinae), Matthew Craig, Daniel Pondella, John Hafner Oct 1999

Analysis Of Age And Growth In Two Eastern Pacific Groupers (Serranidae: Epinephelinae), Matthew Craig, Daniel Pondella, John Hafner

Daniel Pondella

In an attempt to characterize species specific-growth rates of two Eastern Pacific groupers, individuals from two sympatric species, Epinephelus labriformis (n = 173), and Cephalopholis panamensis (n = 127), were collected at various localities in Mexico and the Galápagos archipelago in 1997 and 1998. Sagittal otoliths were removed, and age of each individual was determined by direct visual inspection of annuli present following sectioning. Length/weight relationships were determined, and growth curves were generated using the von Bertalanffy growth model. The two species demonstrated similar growth rates, yet, as determined by the von Bertalanffy parameters, E. labriformis tended towards a larger …


Allometric Scaling Of Production And Life-History Variation In Vascular Plants, Brian Enquist, Geoffrey West, Eric Charnov, James Brown Oct 1999

Allometric Scaling Of Production And Life-History Variation In Vascular Plants, Brian Enquist, Geoffrey West, Eric Charnov, James Brown

Biology Faculty & Staff Publications

A prominent feature of comparative life histories is the well documented negative correlation between growth rate and life span. Patterns of resource allocation during growth and reproduction reflect life-history differences between species. This is particularly striking in tropical forests, where tree species can differ greatly in their rates of growth and ages of maturity but still attain similar canopy sizes. Here we provide a theoretical framework for relating life-history variables to rates of production, dM/ dt, where M is above-ground mass and t is time. As metabolic rate limits production as an individual grows, dM=dt ~M3=4. Incorporating interspecific variation in …


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 Oct 1999

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 …


Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá Oct 1999

Three-Dimensional Reconstructions Of Tadpole Chondrocrania From Historical Sections, Gary Radice, Mary K. Boggiano, Mark Desantis, Peter Larson, Joseph Oppong, Matthew Smetanick, Todd Stevens, James Tripp, Rebecca Weber, Michael Kerckhove, Rafael De Sá

Virginia Journal of Science

Reconstructing three dimensional structures (3DR) from histological sections has always been difficult but is becoming more accessible with the assistance of digital imaging. We sought to assemble a low cost system using readily available hardware and software to generate 3DR for a study of tadpole chondrocrania. We found that a combination of RGB can1era, stereomicro­scope, and Apple Macintosh PowerPC computers running NIH Image, Object Image, Rotater, and SURFdriver software provided acceptable reconstruc­tions. These are limited in quality primarily by the distortions arising from histological protocols rather than hardware or software.


Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr. Oct 1999

Cartilage Regeneration On A Large Articular Surface Facilitated By Stress Shielding, Charles L. Mcdowell, Jennifer S. Wayne, Robert Tuten, Hunter H. Mcguire Jr.

Virginia Journal of Science

An animal model for the study of articular cartilage regeneration in-vivo facilitated by stress-shielding is introduced. The object of the model is to test the hypothesis that some form of cartilaginous tissue will grow upon a large joint surface in vivo with the joint in normal motion. The model utilizes the known capability of immature cells to differentiate. The source of cells is bleeding subchondral bone. In addition, the model provides a mechanically shielded environment in which cell differentiation and maturation can occur. The study showed that a substantial amount of tissue will grow in the animal model only when …


Optical Monitoring And Forecasting Systems For Harmful Algal Blooms: Possibility Or Pipe Dream?, Mark A. Moline, Oscar Schofield, Joe Grzymski, Paul W. Bissett, Gary J. Kirkpatrick, David F. Millie, Collin S. Roesler Oct 1999

Optical Monitoring And Forecasting Systems For Harmful Algal Blooms: Possibility Or Pipe Dream?, Mark A. Moline, Oscar Schofield, Joe Grzymski, Paul W. Bissett, Gary J. Kirkpatrick, David F. Millie, Collin S. Roesler

Biological Sciences

Monitoring programs for harmful algal blooms (HABs) are currently reactive and provide little or no means for advance warning. Given this, the development of algal forecasting systems would be of great use because they could guide traditional monitoring programs and provide a proactive means for responding to HABs. Forecasting systems will require near real-time observational capabilities and hydrodynamic/biological models designed to run in the forecast mode. These observational networks must detect and forecast over ecologically relevant spatial/ temporal scales. One solution is to incorporate a multiplatform optical approach utilizing remote sensing and in situ moored technologies. Recent advances in instrumentation …


Review Of Population Biology Of Grasses, Thomas B. Bragg Oct 1999

Review Of Population Biology Of Grasses, Thomas B. Bragg

Biology Faculty Publications

Population Biology of Grasses provides a wealth of knowledge beyond population biology that ecologists and ecosystem biologists will find relevant to their concerns, particularly those with an interest in grasslands. Though not limited to the Great Plains region, the book would make an excellent addition to the reference shelf of anyone interested in grasses and grassland-related ecosystems, including readers with an interest in land management and preservation. While the papers are written for different levels of readers, all provide information accessible to non-specialists.


The Southern Resident Orcinus Orca Population In Puget Sound: Hypotheses On Population Ratios And The Effects Of The Capture Era On Behavior Of The Whales, Beth Phillips Oct 1999

The Southern Resident Orcinus Orca Population In Puget Sound: Hypotheses On Population Ratios And The Effects Of The Capture Era On Behavior Of The Whales, Beth Phillips

WWU Honors College Senior Projects

This project set out to assess the population status of the southern resident community of Orcinus orca, the killer whale, in Puget Sound. The current number of whales in the community is 84, down from 97 in 1995, and it has been hypothesized that their numbers will continue to decline in the future. The study focused specifically on the residual effects of the capture era in the 1960’s and 1970’s that systematically cropped immature male and female killer whales from the southern resident community. Then, the behavioral adaptations that the killer whales appear to be making in response to …


Action Of Repeat-Induced Point Mutation On Both Strands Of A Duplex And On Tandem Duplications Of Various Sizes In Neurospora, Michael Watters, Thomas Randall, Brian Margolin, Eric Selker, David Stadler Sep 1999

Action Of Repeat-Induced Point Mutation On Both Strands Of A Duplex And On Tandem Duplications Of Various Sizes In Neurospora, Michael Watters, Thomas Randall, Brian Margolin, Eric Selker, David Stadler

Michael Watters

In Neurospora crassa, DNA sequence duplications are detected and altered efficiently during the sexual cycle by a process known as RIP (repeat-induced point mutation). Affected sequences are subjected to multiple GC-to-AT mutations. To explore the pattern in which base changes are laid down by RIP we examined two sets of strains. First, we examined the products of a presumptive spontaneous RIP event at the mtr locus. Results of sequencing suggested that a single RIP event produces two distinct patterns of change, descended from the two strands of an affected DNA duplex. Equivalent results were obtained using an exceptional tetrad from …


The Saccharomyces Cerevisiae Ubiquitin-Proteasome System, Mark Hochstrasser, Phoebe Johnson, Cassandra Arendt, Alexander Amerik, Sowmya Swaminathan, Rob Swanson, Shyr-Jiann Li, Jeffrey Laney, Robin Pals-Rylaarsdam, Jonathan Nowak, Pamela Connerly, M. Yanagida, K. Nasmyth, M. Tyers, R. Hunt, J. Diffley Sep 1999

The Saccharomyces Cerevisiae Ubiquitin-Proteasome System, Mark Hochstrasser, Phoebe Johnson, Cassandra Arendt, Alexander Amerik, Sowmya Swaminathan, Rob Swanson, Shyr-Jiann Li, Jeffrey Laney, Robin Pals-Rylaarsdam, Jonathan Nowak, Pamela Connerly, M. Yanagida, K. Nasmyth, M. Tyers, R. Hunt, J. Diffley

Rob Swanson

Our studies of the yeast ubiquitin-proteasome pathway have uncovered a number of general principles that govern substrate selectivity and proteolysis in this complex system. Much of the work has focused on the destruction of a yeast transcription factor, MAT alpha 2. The alpha 2 protein is polyubiquitinated and rapidly degraded in alpha-haploid cells. One pathway of proteolytic targeting, which depends on two distinct endoplasmic reticulum-localized ubiquitin-conjugating enzymes, recognizes the hydrophobic face of an amphipathic helix in alpha 2. Interestingly, degradation of alpha 2 is blocked in a/alpha-diploid cells by heterodimer formation between the alpha 2 and a1 homeodomain proteins. The …


Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls Sep 1999

Fish Kills And Bottom-Water Hypoxia In The Neuse River And Estuary: Reply To Burkholder Et Al., Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls

Faculty Publications

No abstract provided.