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Articles 4141 - 4170 of 4208

Full-Text Articles in Molecular Biology

Regulation Of Protein Expression By Transforming Growth Factor Beta And Other Growth Modulators , Frederic William Thalacker Jan 1990

Regulation Of Protein Expression By Transforming Growth Factor Beta And Other Growth Modulators , Frederic William Thalacker

Retrospective Theses and Dissertations

The main goal of this project was to understand the signal transduction pathways through which growth modulators such as TGF-[beta], PMA and retinoic acid mediate protein expression and DNA synthesis. Transforming growth factor [beta] (TGF-[beta]) induces synthesis and secretion of a 48,000 M r protein that we have found to be type I plasminogen activator inhibitor (PAI-1). TGF-[beta] induces PAI-1 in every cell line that we have studied including near term mink lung epithelial CCL64 cells, mouse embryo fibroblast AKR-2B 84A cells, African green monkey kidney epithelial BSC-1 cells, and normal rat kidney fibroblast NRK 49F ...


Cell-Wall Components And Lignin Biosynthesis In Forages , James Enderby Bidlack Jan 1990

Cell-Wall Components And Lignin Biosynthesis In Forages , James Enderby Bidlack

Retrospective Theses and Dissertations

Lignin is the major cell-wall (CW) component that lowers forage digestibility. Negative relationships between lignin and forage quality are caused by interactions and variability of lignin with other CW components. This study was conducted to better understand how lignin content, concentration, deposition, and change in concentration vary with other CW components in maturing stems and to provide preliminary information about phenylpropanoid metabolism in relation to lignification;Regrowth from basal stem tissue was sampled weekly or biweekly from greenhouse-grown forage grass and legume species. Samples were collected for a period of about 8 weeks and analyzed for fiber concentration and content ...


Analysis And Characterization Of The Major Histocompatibility Complex Of Domestic Animals , Yuanxin Xu Jan 1990

Analysis And Characterization Of The Major Histocompatibility Complex Of Domestic Animals , Yuanxin Xu

Retrospective Theses and Dissertations

The major histocompatibility complex (MHC) is a family of genes coding for molecules which play important roles in the immune response as well as many other cellular processes of a vertebrate organism. The understanding of the immune system of some of the domestic animals will have both practical value and theoretical significance. The purpose of this work was to study the MHC of the chicken (B) and the swine (SLA). First, in order to study the MHC class II gene structure of the chicken, a genomic library was constructed from an inbred chicken line G-B2 (MHC haplotype B[superscript]6 ...


Genetic And Molecular Analyses Of Suppressor Of Forked In Drosophila Melanogaster , Cynthia Lynn Fitch-Steenson Jan 1990

Genetic And Molecular Analyses Of Suppressor Of Forked In Drosophila Melanogaster , Cynthia Lynn Fitch-Steenson

Retrospective Theses and Dissertations

Mutations at the suppressor of forked, su(f), locus are trans-acting, allele specific suppressors and enhancers of mutations at certain other loci. Su(f) is a trans-acting regulator whose normal product is necessary for proper transcription of these genes. The su(f) product regulates the transcription of transposable elements located within these genes. Our investigation includes a genetic analysis in which a number of new su(f) alleles were isolated, a development analysis in which the effects of new alleles and allelic combinations were characterized, and a molecular analysis in which a cloned genomic DNA fragment containing su(f) was ...


A Lipopolysaccharide-Induced Dna-Binding Protein For A Class Ii Gene In B Cells Is Distinct From Nf-Kappa B, Ellen M. Gravallese, Mark R. Boothby, Cynthia M. Smas, Laurie H. Glimcher Aug 1989

A Lipopolysaccharide-Induced Dna-Binding Protein For A Class Ii Gene In B Cells Is Distinct From Nf-Kappa B, Ellen M. Gravallese, Mark R. Boothby, Cynthia M. Smas, Laurie H. Glimcher

Rheumatology Publications and Presentations

Class II (Ia) major histocompatibility complex molecules are cell surface proteins normally expressed by a limited subset of cells of the immune system. These molecules regulate the activation of T cells and are required for the presentation of antigens and the initiation of immune responses. The expression of Ia in B cells is determined by both the developmental stage of the B cell and by certain external stimuli. It has been demonstrated previously that treatment of B cells with lipopolysaccharide (LPS) results in increased surface expression of Ia protein. However, we have confirmed that LPS treatment results in a significant ...


Collagen Binding Proteins Derived From The Embryonic Fibroblast Cell Surface Recognize Arginine-Glycine-Aspartic Acid, Roy C. Ogle, Charles D. Little Jun 1989

Collagen Binding Proteins Derived From The Embryonic Fibroblast Cell Surface Recognize Arginine-Glycine-Aspartic Acid, Roy C. Ogle, Charles D. Little

Medical Diagnostics & Translational Sciences Faculty Publications

Several cell surface proteins (Mr = 120,000, 90,000, 63,000 and 47,000) apparently integral to embryonic fibroblast plasma membranes were extracted with detergent and isolated by collagen affinity chromatography. Certain of these proteins (Mr = 120,000, 90,000, and 47,000) were specifically eluted from collagen affinity columns by synthetic peptides containing the amino acid sequence arginyl-glycyl-aspartic acid (RGD). These data show that a number of collagen binding proteins exist on the embryonic fibroblast cell surface. Some of the proteins may be collagen receptors binding to RGD sequences in the collagen molecule while at least one of the ...


Identification Of Genes That Interact With Glp-1, A Gene Required For Inductive Cell Interactions In Caenorhabditis Elegans, Eleanor M. Maine, Judith Kimble Jan 1989

Identification Of Genes That Interact With Glp-1, A Gene Required For Inductive Cell Interactions In Caenorhabditis Elegans, Eleanor M. Maine, Judith Kimble

Biology

The glp-1 gene functions in two inductive cellular interactions and in development of the embryonic hypodermis of C. elegans. We have isolated six mutations as recessive suppressors of temperature-sensitive (ts) mutations of glp-1. By mapping and complementation tests, we found that these suppressors are mutations of known dumpy (dpy) genes; dpy genes are required for development of normal body shape. Based on this result, we asked whether mutations previously isolated in screens for mutants defective in body shape could also suppress glp-1(ts). From these tests, we learned that unselected mutations of eight genes required for normal C. elegans morphogenesis ...


A Flow Cytometric Approach To Assessing The Environmental And Physiological Status Of Phytoplankton, Serge Demers, Kimberly Davis, Terry L. Cucci Jan 1989

A Flow Cytometric Approach To Assessing The Environmental And Physiological Status Of Phytoplankton, Serge Demers, Kimberly Davis, Terry L. Cucci

CCPO Publications

No abstract provided.


Isolation Of Upstream Control Regions Of Genes Expressed At Different Times During Growth And Sporulation In Bacillus Thuringiensis , John Michael Hurley Jan 1989

Isolation Of Upstream Control Regions Of Genes Expressed At Different Times During Growth And Sporulation In Bacillus Thuringiensis , John Michael Hurley

Retrospective Theses and Dissertations

To investigate the mechanisms of gene expression in Bacillus thuringiensis subsp. kurstaki HD251, HindIII-digested total DNA was ligated into plasmid pKO1, which contains a promoterless galK gene. E. coli HB101 (GalK[superscript]-) transformant colonies resistant to ampicillin and red in color on MacConkey-galactose agar (indicating transformation to the GalK[superscript]+ phenotype) presumably contain B. thuringiensis DNA inserts in pKO1 that function as promoters in E. coli. To determine if such sequences control gene expression in B. thuringiensis, total RNA probes were prepared from cultures at specified times throughout growth and sporulation and used to screen plasmid DNA "dot-blots." Several plasmids ...


Analysis Of Mutator Activity In Embryogenic Callus Cultures And Regenerated Plants Of Zea Mays L. , Martha Graham James Jan 1989

Analysis Of Mutator Activity In Embryogenic Callus Cultures And Regenerated Plants Of Zea Mays L. , Martha Graham James

Retrospective Theses and Dissertations

Activity of the Mutator transposable element system in maize was assessed in tissue cultures and regenerated plants by Southern analysis of Mu-element modification status and genomic position. Examination of embryogenic callus cultures established from the F[subscript]1's of crosses between active Mutator stock and maize inbreds A188 and H99 determined that the in planta parameters for Mutator activity were maintained in an in vitro environment. Subclonal populations from callus lines were used to demonstrate that Mu elements from active Mutator lines can remain transpositionally active in tissue culture systems. Novel Mu-homologous restriction fragments occurred in 38% of the ...


Sequence Heterogeneity Of Bovine Mitochondrial Dna , Gary Leroy Lindberg Jan 1989

Sequence Heterogeneity Of Bovine Mitochondrial Dna , Gary Leroy Lindberg

Retrospective Theses and Dissertations

The displacement-loop (D-loop) region of bovine mitochondrial DNA (mtDNA) isolated from blood leukocytes was studied. A method was devised for the isolation of mtDNA from blood leukocytes based on detergent lysis of the plasma membrane and removal of cell nuclei by centrifugation. Nucleic acids extracted from the residual cytoplasmic fraction contained mtDNA in quantities sufficient for restriction enzyme analysis and for DNA cloning and sequencing;MtDNA was from a herd of Holstein cattle that was established 1968 from diverse genetic sources. Maternal lineages were traced by pedigree analysis to their earliest origins in the late 1800s. MtDNA was isolated from ...


Development Of Molecular Genetic Approaches To Study Mycoplasma Pathogenesis , Gregory G. Mahairas Jan 1989

Development Of Molecular Genetic Approaches To Study Mycoplasma Pathogenesis , Gregory G. Mahairas

Retrospective Theses and Dissertations

Transposons Tn4001 and Tn916 have been introduced into M. pulmonis. Additionally, the antibiotic resistance genes of both transposable elements have been cloned and integrative plasmids constructed that carry chromosomal DNA as a region of homology. Transposons and integrative plasmids were used to study polyethylene glycol mediated transformation in M. pulmonis and the optimal transformation frequencies were obtained in a mixture containing 35.5% PEG, 10 ug plasmid DNA, 10 ug yeast tRNA and 1 x 10[superscript]8 cells. Transformation frequencies were enhanced four- to five-fold by preincubating cells at 0° C for 30 min. in CaCl[subscript]2 prior ...


Pulsed-Field Gel Electrophoresis Studies Of Rhizobiaceae , Bruno Walther S. Sobral Jan 1989

Pulsed-Field Gel Electrophoresis Studies Of Rhizobiaceae , Bruno Walther S. Sobral

Retrospective Theses and Dissertations

The migration properties of circular, covalently closed (ccc) and linear DNAs were studied in pulsed-field gel electrophoresis as a model system for resolving large plasmids in the Rhizobiaceae. The effects of varying pulse time and agarose concentration on the electrophoretic mobility cccDNAs, ranging from 2 kilobase pairs (kb) to 16 kb, was investigated. We used both field inversion gel electrophoresis (FIGE) and electrophoresis in contour-clamped homogeneous electric fields (CHEF); both ccc and linear molecules had a minimum mobility as a function of pulse time in a CHEF apparatus. Linear and cccDNAs of the same size were affected differently by pulse ...


Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman Jan 1989

Mitochondrial Dna Variation In Striped Bass, Morone Saxatilis, From The Rappahannock River, Virginia, Carol Furman

Dissertations, Theses, and Masters Projects

No abstract provided.


Mrna Decay Rates In Late-Developing Dictyostelium Discoideum Cells Are Heterogeneous, And Cyclic Amp Does Not Act Directly To Stabilize Cell-Type-Specific Mrnas, Richard E. Manrow, Allan Jacobson Oct 1988

Mrna Decay Rates In Late-Developing Dictyostelium Discoideum Cells Are Heterogeneous, And Cyclic Amp Does Not Act Directly To Stabilize Cell-Type-Specific Mrnas, Richard E. Manrow, Allan Jacobson

Open Access Articles

We reevaluated the use of 32PO4 pulse-chases for analyzing mRNA decay rates in late-developing Dictyostelium cells. We found that completely effective PO4 chases could not be obtained in developing cells and that, as a consequence, the decay rates exhibited by some mRNAs were influenced by the rates at which they were transcribed. In developing cells disaggregated in the presence of cyclic AMP, the poly(A)+ mRNA population turned over with an apparent half-life of 4 h, individual mRNA decay rates were heterogeneous, and some prestalk and prespore mRNAs appeared to decay with biphasic kinetics. In cells disaggregated in the absence ...


The Characterization Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Vicky L. Montoya, Wendy L. Murdoch, Roy C. Ogle, John L. Keating, Robert M. Grainger Aug 1988

The Characterization Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Vicky L. Montoya, Wendy L. Murdoch, Roy C. Ogle, John L. Keating, Robert M. Grainger

Medical Diagnostics & Translational Sciences Faculty Publications

We have isolated ribosomal RNA gene (rDNA) chromatin from Physarum polycephalum using a nucleolar isolation procedure that minimizes protein loss from chromatin and, subsequently, either agarose gel electrophoresis or metrizamide gradient centrifugation to purify this chromatin fraction (Amero, S. A., Ogle, R. C., Keating, J. L., Montoya, V. L., Murdoch, W. L., and Grainger, R. M. (1988) J. Biol. Chem. 263, 10725-10733). Metrizamide-purified rDNA chromatin obtained from nucleoli isolated according to the new procedure has a core histone/DNA ratio of 0.77:1. The major core histone classes comigrate electrophoretically with their nuclear counterparts on Triton-acid-urea/sodium dodecyl sulfate ...


In Situ Hybridization Of Complementary Deoxyribonucleic Acid Probes To The 1448-1455 Region Of Escherichia Coli 16s Ribosomal Subunits, Angela Lubbers Apr 1988

In Situ Hybridization Of Complementary Deoxyribonucleic Acid Probes To The 1448-1455 Region Of Escherichia Coli 16s Ribosomal Subunits, Angela Lubbers

Life and Environmental Sciences Undergraduate Theses

30S subunits were isolated from Escherichia coli ribosomes and purified 16S RNA was subsequently extracted. An eight-base DNA oligomer [d(CCCGAAGG)] was hybridized in situ to the 1448-1455 region of the 16S rRNA. The cDNA-rRNA hybrid was digested with the RNA specific enzyme RNase H. The clipped RNA fragments were then separated by polyacrylamide gel electrophoresis. The desired RNA band was visualized by UV shadowing, eluted from the gel and sequenced to verify the specificity of the probe binding. The results suggest that the cDNA and rRNA were binding, but proof that it was specific to the 1448-1455 region is ...


In Situ Hybridization Technique As Applied To Cytogenetics, Daniel Coverdell Apr 1988

In Situ Hybridization Technique As Applied To Cytogenetics, Daniel Coverdell

Life and Environmental Sciences Undergraduate Theses

In our experimentation with the in situ hybridization technique we were unable to band chromosomes with the standard Giemsa staining procedure following autoradiography. Banding was achieved using a replication banding technique in which bromodeoxyuridine (BrdU) was incorporated during replication. The background particles and debris on the chromosomal preparations, which had been in situ hybridized, was reduced by maintaining constant agitation during post-hybridization washes. Excessive background streaks, resulting from cracks in the radiography emulsion, were nearly eliminated by heating the emulsion to 50° C while dipping the slides.


A New Assay For 6-Pyruvoyl Tetrahydropterin Synthase From A Rat Kidney Model, John Connolly Jr. Apr 1988

A New Assay For 6-Pyruvoyl Tetrahydropterin Synthase From A Rat Kidney Model, John Connolly Jr.

Life and Environmental Sciences Undergraduate Theses

The enzyme 6-pyruvoyl tetrahydropterin synthase (PTP synthase) is the second enzyme in a four - step pathway which leads to the production of tetrahydrobiopterin, the cofactor for aromatic amino acid hydroxylations. In attempts to develop an assay, PTP synthase was characterized in terms of what effect its concentration, substrate (dihydroneopterin triphosphate-h^NTP) concentration, incubation time, and cofactor concentration had on product (sepiapterin) formation. In a reaction mixture of 100 pi, sepiapterin production is proportional to enzyme amount only up to 10 pi of enzyme. Sepiapterin production is linear to substrate concentration up to 60 pM after which, sepiapterin production levels off ...


Laminin Receptors For Neurite Formation, H. K. Kleinman, Roy C. Ogle, F. B. Cannon, C. D. Little, T. M. Sweeney, L. Luckenbill-Edds Feb 1988

Laminin Receptors For Neurite Formation, H. K. Kleinman, Roy C. Ogle, F. B. Cannon, C. D. Little, T. M. Sweeney, L. Luckenbill-Edds

Medical Diagnostics & Translational Sciences Faculty Publications

Laminin, a basement membrane glycoprotein promotes both cell attachment and neurite outgrowth. Separate domains on laminin elicit these responses, suggesting that distinct receptors occur on the surface of cells. NG108-15 neuroblastoma-glioma cells rapidly extend long processes in the presence of laminin. We report here that 125I-labeled laminin specifically binds to these cells and to three membrane proteins of 67, 110, and 180 kDa. These proteins were isolated by affinity chromatography on laminin-Sepharose. The 67-kDa protein reacted with antibody to the previously characterized receptor for cell attachment to laminin. Antibodies to the 110-kDa and 180-kDa bands demonstrated that the 110-kDa protein ...


Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick Jan 1988

Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick

Michael Sinensky

We have examined the nuclear localization of isoprenylated proteins in CHO-K1 cells labeled with [14C]mevalonate. Nuclear proteins of 68, 70, and 74 kD, posttranslationally modified by an isoprenoid, are also components of a nuclear matrix-intermediate filament preparation from CHO cells. Furthermore, the 68-, 70-, and 74-kD isoprenylated polypeptides are immunoprecipitated from cell extracts with two different anti-lamin antisera. Based on exact two-dimensional comigration with lamin B, both from rat liver lamin and CHO nuclear matrix-intermediate filament preparations, and its immunoprecipitation with anti-lamin antisera, we conclude that the 68-kD isoprenylated protein found in nuclei from [14C]mevalonate-labeled CHO cells is ...


Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick Jan 1988

Incorporation Of A Product Of Mevalonic Acid Metabolism Into Proteins Of Chinese Hamster Ovary Nuclei, Michael Sinensky, L. A. Beck, T. Hosick

Faculty Publications

We have examined the nuclear localization of isoprenylated proteins in CHO-K1 cells labeled with [14C]mevalonate. Nuclear proteins of 68, 70, and 74 kD, posttranslationally modified by an isoprenoid, are also components of a nuclear matrix-intermediate filament preparation from CHO cells. Furthermore, the 68-, 70-, and 74-kD isoprenylated polypeptides are immunoprecipitated from cell extracts with two different anti-lamin antisera. Based on exact two-dimensional comigration with lamin B, both from rat liver lamin and CHO nuclear matrix-intermediate filament preparations, and its immunoprecipitation with anti-lamin antisera, we conclude that the 68-kD isoprenylated protein found in nuclei from [14C]mevalonate-labeled CHO cells is ...


Comparison Of Cyclic Nucloetide Phosphodiesterase In Physarum Favicomum, C. Kay Holtman, Tammy K. Ebsen, Judith A. Bean, J. Scott Bryles, Thomas J. Lynch Jan 1988

Comparison Of Cyclic Nucloetide Phosphodiesterase In Physarum Favicomum, C. Kay Holtman, Tammy K. Ebsen, Judith A. Bean, J. Scott Bryles, Thomas J. Lynch

Journal of the Arkansas Academy of Science

We have studied both cyclic AMP phosphodiesterase and cyclic GMP phosphodiesterase in the myxomycete Physarum flavicomum. The cyclic AMP phosphodiesterase preparations were isolated from both the diploid plasmodial stage of the lifecycle and the haploid myxamoebal stage. The plasmodial enzyme was prepared from spent medium (extracellular) and also from purified nuclei. The myxamoebal enzyme was prepared from purified nuclei. Cyclic GMP phosphodiesterase activity was studied in purified nuclei isolated from the plasmodium. One unusual feature of all the enzymes from the plasmodium is extreme heat stability; they remain catalytically active even after exposure to a boiling water bath for twenty ...


The Purification Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Roy C. Ogle, John L. Keating, Vicky L. Montoya, Wendy L. Murdoch, Robert M. Grainger Jan 1988

The Purification Of Ribosomal Rna Gene Chromatin From Physarum Polycephalum, Sally A. Amero, Roy C. Ogle, John L. Keating, Vicky L. Montoya, Wendy L. Murdoch, Robert M. Grainger

Medical Diagnostics & Translational Sciences Faculty Publications

We have undertaken the purification of ribosomal RNA gene (rDNA) chromatin from the slime mold Physarum polycephalum, in order to study its chromatin structure. In this organism rDNA exists in nucleoli as highly repeated minichromosomes, and one can obtain crude chromatin fractions highly enriched in rDNA from isolated nucleoli. We first developed a nucleolar isolation method utilizing polyamines as stabilization agents that results in a chromatin fraction containing far more protein than is obtained by the more commonly used divalent cation isolation methods. The latter method appears to result in extensive histone loss during chromatin isolations. Two methods were then ...


Photoreactivation Of Lethal Damage Induced In Hamster X Xenopus Hybrid Cells And Their Parentals By Uv Light, David Bohlender, Stuart Williams, Emir Cruz, H. Gaston Griggs Jan 1987

Photoreactivation Of Lethal Damage Induced In Hamster X Xenopus Hybrid Cells And Their Parentals By Uv Light, David Bohlender, Stuart Williams, Emir Cruz, H. Gaston Griggs

Journal of the Arkansas Academy of Science

A85 Xenopus cells that exhibited a high level of photoreactivation (PR) and V79B2 hamster cells that exhibited little PR were fused to produce the V79B2 x A85 cell line — a hybrid line which possessed a relatively stable karyotype, with most cells containing the entire V79B2 and A85 genomes. UV and UV plus PR fluence-survival relations were then determined and compared for the hybrid and parental lines in a first attempt to elucidate interactions of the parental PR mechanisms in the hybrid. It was anticipated that the A85 genome in the hybrid would produce PR enzyme in sufficient concentration and of ...


Short-Term Feedback Regulation Of Camp By Accelerated Degradation In Rat Tissues, Tom W. Gettys, Peter F. Blackmore, J. Bruce Redmon, Stephen J. Beebe, Jackie D. Corbin Jan 1987

Short-Term Feedback Regulation Of Camp By Accelerated Degradation In Rat Tissues, Tom W. Gettys, Peter F. Blackmore, J. Bruce Redmon, Stephen J. Beebe, Jackie D. Corbin

Bioelectrics Publications

A recent study showed that cAMP analogs lowered cAMP levels in rat hepatocytes. The present work demonstrates that cAMP analogs also lowered cAMP in a rapid, concentration-dependent manner in heart and fat cells. In order to determine if the cAMP-dependent protein kinase mediated this effect, techniques were developed to assay the protein kinase activity ratio in hepatocytes treated with cAMP analogs. The activation of protein kinase and phosphorylase in hepatocytes by 8-pClΦS-cAMP (where 8-pClΦS- indicates 8-parachlorothiophenyl-) was concentration-dependent and occurred in parallel to proportionate decreases in cAMP. More than 20% of the cAMP binding sites on the protein kinase were ...


The Construction And Properties Of An Integrable Plasmid For Genomic Analysis In Staphylococcus Aureus , John Bernard Luchansky Jan 1987

The Construction And Properties Of An Integrable Plasmid For Genomic Analysis In Staphylococcus Aureus , John Bernard Luchansky

Retrospective Theses and Dissertations

An improved system for transforming protoplasts of Staphylococcus aureus with plasmid DNA was developed to facilitate the construction of an integrable plasmid. Protoplast transformants were recovered at higher frequencies when the protoplasts were warmed to 56 C immediately prior to the addition of cesium chloride-purified plasmid DNAs. More transformants were recovered when the protoplast-DNA mixture was plated on R agar than on DM3 medium, and when the selective agent was incorporated directly in the medium rather than supplied in an agar overlay. More transformants were recovered when the protoplast-DNA mixture was incubated at 30 C for 3.5 h before ...


The Mouse Major Histocompatibility Complex And Age-Related Changes In The Murine Immune System , Terry Euclaire Meyer Jan 1987

The Mouse Major Histocompatibility Complex And Age-Related Changes In The Murine Immune System , Terry Euclaire Meyer

Retrospective Theses and Dissertations

A and C57BL/6 inbred mice were used as models for investigating interactions between aging processes and the genes that regulate the immune system, the major histocompatibility complex (MHC, H-2) genes. The C57BL/6 (H-2[superscript] b) mice exhibited significantly longer mean lifespans than the A (H-2[superscript] a) mice, as has been observed by other investigators. Backcross and F[subscript] 2 generation offspring from the parental A and C57BL/6 mice were tested for dependence of longevity upon H-2 type. The effects of H-2 type upon lifespan were statistically significant only for the oldest surviving (i.e., "10[superscript ...


The Metabolism And Localization Of Two Proteins During Heat Shock Of Tetrahymena Thermophila , Thomas William Mcmullin Jan 1987

The Metabolism And Localization Of Two Proteins During Heat Shock Of Tetrahymena Thermophila , Thomas William Mcmullin

Retrospective Theses and Dissertations

When T. thermophila is subjected to hyperthermal stress, it immediately but transiently represses the synthesis of the normal array of proteins (non-hsps) and induces the synthesis of the heat shock protein (hsps). These changes in protein synthetic patterns are controlled at both the transcriptional and translational levels;To determine whether the translational regulatory events could be correlated with changes in the protein synthetic machinery, heat shock induced modifications of the ribosomal proteins were investigated. Of particular interest was the heat shock induced association of a 22 kDa protein, p22, with the small subunit of the ribosome. The synthesis of p22 ...


Yeast Mannans: Use As A Transport Vehicle For Peptides, Jacqueline Cesario Lee Apr 1986

Yeast Mannans: Use As A Transport Vehicle For Peptides, Jacqueline Cesario Lee

Master's Theses

Yeast mannans are phosphorylated glycopeptides found in various species of yeast. Their similarity to the mannose-phosphate signal for intracellular lysosomal uptake led mannans to be considered as a possible vehicle for increasing cellular affinity for peptides. Insulin was used as a model peptide and was conjugated to mannans by two coupling methods. The conjugated mannan-insulins were compared to insulin on the basis of cellular binding and ability to induce typical insulin biological effects.