Student Service to the High School Forensics Community: Insights Gained from Hosting the Annual Singletary Speech and Debate Tournament

Kelsey Bruce discusses student engagement at Linfield College with regard to hosting the annual Singletary Speech and Debate Tournament.https://digitalcommons.linfield.edu/inauguration2019_students/1002/thumbnail.jp

Fluorescent Visualization of In Vitro Mitochondrial DNA Transcription

Mitochondria are important organelles within eukaryotic cells especially for their role in metabolism and ATP production by the oxidative phosphorylation (OXPHOS) pathway. In human cells there are approximately 80 protein subunits that make up the OXPHOS pathway, thirteen of which are encoded by the mitochondrial genome (mtDNA). Mitochondria house all the transcription and translation machinery (i.e., mitochondrial RNA polymerase, mitochondrial ribosome, tRNAs, etc.) required to produce those thirteen mtDNA encoded subunits. In vitro mitochondrial transcription is a method that utilizes recombinantly purified proteins and linear mitochondrial DNA templates to investigate transcription regulation of the organelle. To visualize the products of in vitro transcription, it is still common practice to utilize radioactive nucleotides or staining with ethidium bromide. These conditions can be undesirable due to safety hazards, expense, interference with electrophoresis, and time demands. As an alternative, fluorescent dyes have been developed for DNA and RNA tagging. This work establishes a procedure for post-staining of T7 RNA polymerase in vitro transcription products run via denaturing gel electrophoresis and stained with Gel Red and SYBR Gold dyes. Our current studies focus on applying this procedure to the in vitro mitochondrial transcription assay

Living, Learning, and Leading at Linfield College

Kelsey Bruce discusses student engagement at Linfield College with regard to leadership through student/faculty collaborative research with Dr. Megan Bestwick, speech and debate, and the Linfield Residence Life team.https://digitalcommons.linfield.edu/inauguration2019_students/1003/thumbnail.jp

In Vitro Analysis of the Thyroid Hormone Receptor in Mitochondrial Transcription

The central dogma theory relates how DNA is transcribed into messenger RNA (mRNAs) and then translated into proteins. Since the nucleus contains the majority of the DNA in cells, research related to transcription and translation focuses on these processes within the nucleus and cytosol; however, these processes are also taking place within the mitochondrial organelle. Mitochondria are most widely known for their essential role in producing energy for the cell, but the organelle also contains its own small, circular genome. Transcription of mitochondrial DNA (mtDNA) follows similar mechanisms as does transcription of nuclear DNA. During this essential process, specific mitochondrial transcription factors, such as TFAM and TFB2M, regulate the attachment of the mitochondrial RNA polymerase (POLRMT) to the promoter and initiation of transcription. With a fully functioning mitochondrial RNA polymerase, transcription is properly conducted, and transcripts can be translated to protein by the mitochondrial ribosome. Mitochondrial transcription is a major regulatory process within the organelle, and determining transcription factors involved in this control point is important for understanding mitochondrial function and many diseases relating to mitochondrial dysfunction. Numerous transcription factors are found both in the nucleus as well as in the mitochondria where their function is not well understood. One such transcription factor is the thyroid hormone receptor. Previous research suggests that when the hormone triiodothyronine (T3) is present and taken up in cells, mitochondrial transcription increases. The mechanism behind the T3 stimulation of transcription is thought to be a coordinated effect by interacting with both the mitochondrial and nuclear thyroid hormone receptor. Our aim is to analyze the level of interaction that the mitochondrial thyroid hormone receptor (mt-TRalpha1) has with the mitochondrial DNA and other core mitochondrial transcription factors in the presence and absence of the T3 hormone. With this information, we further understand another component of mitochondrial transcription that could have implications in mitochondrial dysfunction and disease

Authenticating Secure Tokens Using Slow Memory Access

We present an authentication protocol that allows a token, such as a smart card, to authenticate itself to a back-end trusted computer system through an untrusted reader. This protocol relies on the fact that the token will only respond to queries slowly, and that the token owner will not sit patiently while the reader seems not to be working. This protocol can be used alone, with "dumb" memory tokens or with processor-based tokens

Cerebellum Transcriptome of Mice Bred for High Voluntary Activity Offers Insights into Locomotor Control and Reward-Dependent Behaviors.

The role of the cerebellum in motivation and addictive behaviors is less understood than that in control and coordination of movements. High running can be a self-rewarding behavior exhibiting addictive properties. Changes in the cerebellum transcriptional networks of mice from a line selectively bred for High voluntary running (H) were profiled relative to an unselected Control (C) line. The environmental modulation of these changes was assessed both in activity environments corresponding to 7 days of Free (F) access to running wheel and to Blocked (B) access on day 7. Overall, 457 genes exhibited a significant (FDR-adjusted P-value < 0.05) genotype-by-environment interaction effect, indicating that activity genotype differences in gene expression depend on environmental access to running. Among these genes, network analysis highlighted 6 genes (Nrgn, Drd2, Rxrg, Gda, Adora2a, and Rab40b) connected by their products that displayed opposite expression patterns in the activity genotype contrast within the B and F environments. The comparison of network expression topologies suggests that selection for high voluntary running is linked to a predominant dysregulation of hub genes in the F environment that enables running whereas a dysregulation of ancillary genes is favored in the B environment that blocks running. Genes associated with locomotor regulation, signaling pathways, reward-processing, goal-focused, and reward-dependent behaviors exhibited significant genotype-by-environment interaction (e.g. Pak6, Adora2a, Drd2, and Arhgap8). Neuropeptide genes including Adcyap1, Cck, Sst, Vgf, Npy, Nts, Penk, and Tac2 and related receptor genes also exhibited significant genotype-by-environment interaction. The majority of the 183 differentially expressed genes between activity genotypes (e.g. Drd1) were under-expressed in C relative to H genotypes and were also under-expressed in B relative to F environments. Our findings indicate that the high voluntary running mouse line studied is a helpful model for understanding the molecular mechanisms in the cerebellum that influence locomotor control and reward-dependent behaviors

Combinatorial control of temporal gene expression in the Drosophila wing by enhancers and core promoters

Abstract Background The transformation of a developing epithelium into an adult structure is a complex process, which often involves coordinated changes in cell proliferation, metabolism, adhesion, and shape. To identify genetic mechanisms that control epithelial differentiation, we analyzed the temporal patterns of gene expression during metamorphosis of the Drosophila wing. Results We found that a striking number of genes, approximately 50% of the Drosophila transcriptome, exhibited changes in expression during a time course of wing development. While cis-acting enhancer sequences clearly correlated with these changes, a stronger correlation was discovered between core-promoter types and the dynamic patterns of gene expression within this differentiating tissue. In support of the hypothesis that core-promoter type influences the dynamics of expression, expression levels of several TATA-box binding protein associated factors (TAFs) and other core promoter-associated components changed during this developmental time course, and a testes-specific TAF (tTAF) played a critical role in timing cellular differentiation within the wing. Conclusions Our results suggest that the combinatorial control of gene expression via cis-acting enhancer sequences and core-promoter types, determine the complex changes in gene expression that drive morphogenesis and terminal differentiation of the Drosophila wing epithelium.http://deepblue.lib.umich.edu/bitstream/2027.42/112935/1/12864_2012_Article_4965.pd

A Randomized Controlled Trial of an Outpatient Protocol for Transitioning Children from Tube to Oral Feeding: No Need for Amitriptyline.

ObjectiveTo assess the role of amitriptyline in the effectiveness of an outpatient protocol for weaning medically complicated children from tube to oral feeding.Study designTwenty-one children seen in multidisciplinary outpatient feeding teams across 4 sites were recruited to a randomized placebo-controlled trial of a 6-month outpatient treatment protocol with behavioral, oral-motor, nutrition, and medication components.ResultsAll of the children who completed the 6-month program (73%) were weaned to receive only oral feeding, regardless of group assignment. The transition from tube to oral feeding resulted in decreases in body mass index percentile and pain, some improvements in quality of life, and no statistically significant changes in cost.ConclusionsAmitriptyline is not a key component of this otherwise effective outpatient, interdisciplinary protocol for weaning children from tube to oral feeding.Trial registrationClinicalTrials.gov: NCT01206478