Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 9 of 9

Full-Text Articles in Life Sciences

Functional Association Between Three Archaeal Aminoacyl-Trna Synthetases, Mette Praetorius-Ibba, Corinne D. Hausmann, Molly Paras, Theresa E. Rogers, Michael Ibba Dec 2006

Functional Association Between Three Archaeal Aminoacyl-Trna Synthetases, Mette Praetorius-Ibba, Corinne D. Hausmann, Molly Paras, Theresa E. Rogers, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) are responsible for attaching amino acids to their cognate tRNAs during protein synthesis. In eukaryotes aaRSs are commonly found in multi-enzyme complexes, although the role of these complexes is still not completely clear. Associations between aaRSs have also been reported in archaea, including a complex between prolyl-(ProRS) and leucyl-tRNA synthetases (LeuRS) in Methanothermobacter thermautotrophicus that enhances tRNAPro aminoacylation. Yeast two-hybrid screens suggested that lysyl-tRNA synthetase (LysRS) also associates with LeuRS in M. thermautotrophicus. Co-purification experiments confirmed that LeuRS, LysRS, and ProRS associate in cell-free extracts. LeuRS bound LysRS and ProRS with a comparable KD …


Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough Oct 2006

Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough

Eric Blough

This study tested the hypothesis that age-related changes in the dystrophin–glycoprotein complex (DGC) may precede age-associated alterations in muscle morphology and function. Compared to those in adult (6 month) rats, extensor digitorum longus (EDL) and soleus muscle mass was decreased in old (30 month) and very old (36 month) Fischer 344/NNiaHSD 3 Brown Norway/ BiNia rats. The amount of dystrophin, b-dystroglycan, and a-sarcoglycan increased with aging in the EDL and decreased with aging in the soleus. a-Dystroglycan levels were increased with aging in both muscles and displayed evidence of altered glycosylation. Immunostaining for the presence of antibody infiltration and dystrophin …


Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough Oct 2006

Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough

Kevin M Rice

This study tested the hypothesis that age-related changes in the dystrophin–glycoprotein complex (DGC) may precede age-associated alterations in muscle morphology and function. Compared to those in adult (6 month) rats, extensor digitorum longus (EDL) and soleus muscle mass was decreased in old (30 month) and very old (36 month) Fischer 344/NNiaHSD 3 Brown Norway/ BiNia rats. The amount of dystrophin, b-dystroglycan, and a-sarcoglycan increased with aging in the EDL and decreased with aging in the soleus. a-Dystroglycan levels were increased with aging in both muscles and displayed evidence of altered glycosylation. Immunostaining for the presence of antibody infiltration and dystrophin …


Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough Oct 2006

Age-Related Dystrophin–Glycoprotein Complex Structure And Function In The Rat Extensor Digitorum Longus And Soleus Muscle, Kevin M. Rice, Deborah L. Preston, David Neff, Michael L. Norton, Eric R. Blough

Deborah L Preston

This study tested the hypothesis that age-related changes in the dystrophin–glycoprotein complex (DGC) may precede age-associated alterations in muscle morphology and function. Compared to those in adult (6 month) rats, extensor digitorum longus (EDL) and soleus muscle mass was decreased in old (30 month) and very old (36 month) Fischer 344/NNiaHSD 3 Brown Norway/ BiNia rats. The amount of dystrophin, b-dystroglycan, and a-sarcoglycan increased with aging in the EDL and decreased with aging in the soleus. a-Dystroglycan levels were increased with aging in both muscles and displayed evidence of altered glycosylation. Immunostaining for the presence of antibody infiltration and dystrophin …


Molecular Analysis Of The Effects Of Atrazine On Xenopus Laevis Frogs, Ronald Edward Celestine Jul 2006

Molecular Analysis Of The Effects Of Atrazine On Xenopus Laevis Frogs, Ronald Edward Celestine

Dissertations

Atrazine, the most commonly used herbicide in the U.S., has been implicated as one of the factors that may be causing the worldwide decline of amphibians. First, I examined effects of atrazine on laboratory raised Xenopus laevis tadpoles, treated from 5 days post fertilization to NF stage 65/66 with a concentrationof 25 ppb of atrazine. This study showed no significant difference in body weight, length and metamorphic rate.

Second, I used DNA microarrays to examine mRNA expression levels of genes in atrazine treated and control Xenopus laevis tadpoles. I found significant changes in gene expression levels of 18 genes. These …


Aspartyl-Trna Synthetase Is The Target Of Peptidenucleotide Antibiotic Microcin C, Anastasia Metlitskaya, Teymur Kazakov, Aigar Kommer, Olga Pavlova, Mette Praetorius-Ibba, Michael Ibba, Igor Krasheninnkov, Vyacheslav Kolb, Inessa Khmel, Konstantin Severinov Mar 2006

Aspartyl-Trna Synthetase Is The Target Of Peptidenucleotide Antibiotic Microcin C, Anastasia Metlitskaya, Teymur Kazakov, Aigar Kommer, Olga Pavlova, Mette Praetorius-Ibba, Michael Ibba, Igor Krasheninnkov, Vyacheslav Kolb, Inessa Khmel, Konstantin Severinov

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Microcin C is a ribosome-synthesized heptapeptide that contains a modified adenosine monophosphate covalently attached to the C-terminal aspartate. Microcin C is a potent inhibitor of bacterial cell growth. Based on the in vivo kinetics of inhibition of macromolecular synthesis, Microcin C targets translation, through a mechanism that remained undefined. Here, we show that Microcin C is a subject of specific degradation inside the sensitive cell. The product of degradation, a modified aspartyl-adenylate containing an N-acylphosphoramidate linkage, strongly inhibits translation by blocking the function of aspartyl-tRNA synthetase.


Mineralized Bone Allograft In Maxillary Sinuses Histology And Histomorphometry, Sammy Stefan Noumbissi Mar 2006

Mineralized Bone Allograft In Maxillary Sinuses Histology And Histomorphometry, Sammy Stefan Noumbissi

Loma Linda University Electronic Theses, Dissertations & Projects

Background: Demineralized freeze-dried bone allografts (DFDBA) and deproteinized bovine bone xenografts (DMBBX) have been used for sinus augmentation for many years with varying results, but very little has been reported on the clinical efficacy or the histological analysis of mineralized solvent dehydrated bone allografts (MSDBA) as sinus graft materials. This study histologically and histomorphometrically evaluated an MSDBA material called PUROS to augment atrophic human maxillary sinuses.

Materials & Methods: Seven partially and completely edentulous patients requiring unilateral (n=4) or bilateral (n=3) sinus grafts prior to implant placement were selected for this study. Test grafts consisted of MSDBA, and control …


C To U Editing Stimulates A To I Editing In The Anticodon Loop Of A Cytoplasmic Threonyl Trna In Trypanosoma Brucei, Mary Anne T. Rubio, Frank L. Ragone, Kirk W. Gaston, Michael Ibba, Juan D. Alfonzo Jan 2006

C To U Editing Stimulates A To I Editing In The Anticodon Loop Of A Cytoplasmic Threonyl Trna In Trypanosoma Brucei, Mary Anne T. Rubio, Frank L. Ragone, Kirk W. Gaston, Michael Ibba, Juan D. Alfonzo

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Editing of tRNAs is widespread in nature and either changes the decoding properties or restores the folding of a tRNA. Unlike the phylogenetically disperse adenosine (A) to inosine (I) editing, cytosine (C) to uridine (U) editing has only been previously described in organellar tRNAs. We have shown that cytoplasmic tRNAThr(AGU) undergoes two distinct editing events in the anticodon loop: C to U and A to I. In vivo, every inosine-containing tRNAThr is also C to U edited at position 32. In vitro, C to U editing stimulates conversion of A to I at the wobble base. Although …


Characterization Of 35 Microsatellite Loci In The Pacific Lion-Paw Scallop (Nodipecten Subnodosus) And Their Cross-Species Amplification In Four Other Scallops Of The Pectinidae Family, Ana M. Ibarra, Jessica Lynn Petersen, Thomas R. Famula, Bernie May Jan 2006

Characterization Of 35 Microsatellite Loci In The Pacific Lion-Paw Scallop (Nodipecten Subnodosus) And Their Cross-Species Amplification In Four Other Scallops Of The Pectinidae Family, Ana M. Ibarra, Jessica Lynn Petersen, Thomas R. Famula, Bernie May

Department of Animal Science: Faculty Publications

Four microsatellite-enriched DNA libraries yielded 35 microsatellite loci from 100 primer pairs designed for Pacific lion-paw scallop, Nodipecten subnodosus. The number of alleles ranged from four to 28. Three of the 35 loci were not in Hardy–Weinberg equilibrium and linkage disequilibrium was found for one pair of loci. These microsatellites will be used to analyze the population structure of the species in Mexico’s Baja Peninsula to propose management strategies for scallop aquaculture development. Twenty-six primer pairs cross-amplified in Nodipecten nodosus, whereas none (Argopecten ventricosus) or few cross-amplified in the Argopecten species.