Differential functional rescue of Lys513 and Lys516 processing mutants of MRP1 (ABCC1) by chemical chaperones reveals different domain–domain interactions of the transporter

AbstractMultidrug resistance protein 1 (MRP1) extrudes drugs as well as pharmacologically and physiologically important organic anions across the plasma membrane in an ATP-dependent manner. We previously showed that Ala substitutions of Lys513 and Lys516 in the cytoplasmic loop (CL5) connecting transmembrane helix 9 (TM9) to TM10 cause misfolding of MRP1, abrogating its expression at the plasma membrane in transfected human embryonic kidney (HEK) cells. Exposure of HEK cells to the chemical chaperones glycerol, DMSO, polyethylene glycol (PEG) and 4-aminobutyric acid (4-PBA) improved levels of K513A to wild-type MRP1 levels but transport activity was only fully restored by 4-PBA or DMSO treatments. Tryptic fragmentation patterns and conformation-dependent antibody immunoreactivity of the transport-deficient PEG- and glycerol-rescued K513A proteins indicated that the second nucleotide binding domain (NBD2) had adopted a more open conformation than in wild-type MRP1. This structural change was accompanied by differences in ATP binding and hydrolysis but no changes in substrate Km. In contrast to K513A, K516A levels in HEK cells were not significantly enhanced by chemical chaperones. In more permissive insect cells, however, K516A levels were comparable to wild-type MRP1. Nevertheless, organic anion transport by K516A in insect cell membranes was reduced by >80% due to reduced substrate Km. Tryptic fragmentation patterns indicated a more open conformation of the third membrane spanning domain of MRP1. Thus, despite their close proximity to one another in CL5, Lys513 and Lys516 participate in different interdomain interactions crucial for the proper folding and assembly of MRP1

GK-12: NSF Graduate Teaching Fellows in K-12 Education at the University of Maine

Eight districts in central Maine that comprise the Penobscot River Educational Partnership (PREP); four of them, including Maine Indian Education, partners in a current GK-12 project, have joined with the University of Maine to form Fellow-teacher teams to introduce K-12 students to experiments, field trips, and discussions in areas such as chemistry, climate change, marine sciences, molecular biology, geology, food sciences, and ecology. The program is: a) helping teachers and students reach the State of Maine\u27s legislatively-mandated standards for Science & Technology (the Maine Learning Results), b) strengthening Fellows\u27 communication and teaching skills, c) providing professional development for Teachers, d) enriching science for K-12 students, e) providing young male and female role models of SMET professionals to children in grades 3-11, and f) strengthening contacts between GK-12 science faculty and K-12 districts. The K-12 students are monitoring water chemistry and species diversity and abundance in cooperating federal wildlife refuges in areas near them. These shared monitoring activities link classes throughout the entire scope of the project. The spatially and temporally distributed data enables the teams to introduce interesting analyses and discussions across partner classes interacting through videoconferences. Each Fellow works intensively with two teachers in PREP and with a teacher from eastern Maine (Washington & Hancock Counties), western Maine (Madison), or southern Maine (Damariscotta, site of the University of Maine\u27s marine sciences laboratory). The power of Maine\u27s network of ATM classrooms, is being used to expand the Fellows\u27 role modeling and introduce Fellows to a variety of teaching styles. The broader impacts of the project include strengthened backgrounds in science and attendance at the Maine summer Science Camp for the cooperating teachers. The K-12 districts\u27 benefits include the enriched learning of their students and access to the equipment from microscopes to thermal cyclers that is necessary to meet the goals of the Learning Results, but which many districts lack. The University of Maine is benefiting from K-12 students who come to the University better prepared in science and is fulfilling its mission as a Land Grant/Sea Grant institution to serve both the state of Maine and the nation as a whole

A Revolutionary Model to Improve Science Education, Teachers, and Scientists

To meet many modern global challenges, we need to promote scientific and technical literacy. The U.S. National Science Foundation (NSF) supports a “revolutionary” program to connect science education at all levels, from elementary through graduate school. The authors demonstrate how Maine has benefited from this program. They describe the University of Maine’s NSF-funded “GK-12 STEM” program, which placed graduate and advanced undergraduate science and technology students in elementary, middle, and high school classrooms; provided equipment for the schools; and offered training and professional development for the partner teachers. The authors urge the state, universities, and school districts to continue to use this model to increase science literacy and research capacity

Diurnal Cortisol and Survival in Epithelial Ovarian Cancer

IntroductionHypothalamic-pituitary-adrenal (HPA) deregulation is commonly observed in cancer patients, but its clinical significance is not well understood. We prospectively examined the association between HPA activity, tumor-associated inflammation, and survival in ovarian cancer patients prior to treatment.Materials and methodsParticipants were 113 women with ovarian cancer who provided salivary cortisol for three days prior to treatment for calculation of cortisol slope, variability, and night cortisol. Cox proportional hazard regression analyses were used to examine associations between cortisol and survival in models adjusting for disease stage, tumor grade, cytoreduction and age. On a subsample of 41 patients with advanced disease ascites fluid was assayed for levels of interleukin-6 (IL-6) and correlated with cortisol variables.ResultsEach cortisol measure was associated with decreased survival time, adjusting for covariates (all p<.041). A one standard deviation increase in night cortisol was associated with a 46% greater likelihood of death. Patients in the high night cortisol group survived an estimated average of 3.3 years compared to 7.3 years for those in the low night cortisol group. Elevated ascites IL-6 was associated with each cortisol measure (all r>36, all p<.017).DiscussionAbnormal cortisol rhythms assessed prior to treatment are associated with decreased survival in ovarian cancer and increased inflammation in the vicinity of the tumor. HPA abnormalities may reflect poor endogenous control of inflammation, dysregulation caused by tumor-associated inflammation, broad circadian disruption, or some combination of these factors. Nocturnal cortisol may have utility as a non-invasive measure of HPA function and/or disease severity

Calcium Homeostasis in Myogenic Differentiation Factor 1 (MyoD)-Transformed, Virally-Transduced, Skin-Derived Equine Myotubes

Dysfunctional skeletal muscle calcium homeostasis plays a central role in the pathophysiology of several human and animal skeletal muscle disorders, in particular, genetic disorders associated with ryanodine receptor 1 (RYR1) mutations, such as malignant hyperthermia, central core disease, multiminicore disease and certain centronuclear myopathies. In addition, aberrant skeletal muscle calcium handling is believed to play a pivotal role in the highly prevalent disorder of Thoroughbred racehorses, known as Recurrent Exertional Rhabdomyolysis. Traditionally, such defects were studied in human and equine subjects by examining the contractile responses of biopsied muscle strips exposed to caffeine, a potent RYR1 agonist. However, this test is not widely available and, due to its invasive nature, is potentially less suitable for valuable animals in training or in the human paediatric setting. Furthermore, increasingly, RYR1 gene polymorphisms (of unknown pathogenicity and significance) are being identified through next generation sequencing projects. Consequently, we have investigated a less invasive test that can be used to study calcium homeostasis in cultured, skin-derived fibroblasts that are converted to the muscle lineage by viral transduction with a MyoD (myogenic differentiation 1) transgene. Similar models have been utilised to examine calcium homeostasis in human patient cells, however, to date, there has been no detailed assessment of the cells’ calcium homeostasis, and in particular, the responses to agonists and antagonists of RYR1. Here we describe experiments conducted to assess calcium handling of the cells and examine responses to treatment with dantrolene, a drug commonly used for prophylaxis of recurrent exertional rhabdomyolysis in horses and malignant hyperthermia in humans

Mitochondria in epithelial ovarian carcinoma exhibit abnormal phenotypes and blunted associations with biobehavioral factors

Malignant tumor cells exhibit mitochondrial alterations and are also influenced by biobehavioral processes, but the intersection of biobehavioral factors and mitochondria in malignant tumors remains unexplored. Here we examined multiple biochemical and molecular markers of mitochondrial content and function in benign tissue and in high-grade epithelial ovarian carcinoma (EOC) in parallel with exploratory analyses of biobehavioral factors. First, analysis of a publicly-available database (n = 1435) showed that gene expression of specific mitochondrial proteins in EOC is associated with survival. Quantifying multiple biochemical and molecular markers of mitochondrial content and function in tissue from 51 patients with benign ovarian masses and 128 patients with high-grade EOC revealed that compared to benign tissue, EOCs exhibit 3.3–8.4-fold higher mitochondrial content and respiratory chain enzymatic activities (P < 0.001) but similar mitochondrial DNA (mtDNA) levels (− 3.1%), documenting abnormal mitochondrial phenotypes in EOC. Mitochondrial respiratory chain activity was also associated with interleukin-6 (IL-6) levels in ascites. In benign tissue, negative biobehavioral factors were inversely correlated with mitochondrial content and respiratory chain activities, whereas positive biobehavioral factors tended to be positively correlated with mitochondrial measures, although effect sizes were small to medium (r = − 0.43 to 0.47). In contrast, serous EOCs showed less pronounced biobehavioral-mitochondrial correlations. These results document abnormal mitochondrial functional phenotypes in EOC and warrant further research on the link between biobehavioral factors and mitochondria in cancer

B806: Performance Evaluations of Potato Clones and Varieties in the Northeastern States 1984

Cooperative potato clone and variety trials were conducted at 32 locations to determine field performance of selected clones and varieties grown under soil, climatic, and cultural management common to the potato growing areas of 12 cooperating states and the Province of New Brunswick, Canada. A few locations also evaluated storage and processing behavior of selected clones and varieties. These tests are contributions to Regional Project NE107 entitled, Breeding and Evaluation of New Potato Clones for the Northeast. The primary objective of this project is to determine clone performance and stability over a wide range of soil, climate, and cultural conditions.https://digitalcommons.library.umaine.edu/aes_bulletin/1117/thumbnail.jp

Genome-wide association study of primary tooth eruption identifies pleiotropic loci associated with height and craniofacial distances

Twin and family studies indicate that the timing of primary tooth eruption is highly heritable, with estimates typically exceeding 80%. To identify variants involved in primary tooth eruption we performed a population based genome-wide association study of ‘age at first tooth’ and ‘number of teeth’ using 5998 and 6609 individuals respectively from the Avon Longitudinal Study of Parents and Children (ALSPAC) and 5403 individuals from the 1966 Northern Finland Birth Cohort (NFBC1966). We tested 2,446,724 SNPs imputed in both studies. Analyses were controlled for the effect of gestational age, sex and age of measurement. Results from the two studies were combined using fixed effects inverse variance meta-analysis. We identified a total of fifteen independent loci, with ten loci reaching genome-wide significance (p<5x10−8) for ‘age at first tooth’ and eleven loci for ‘number of teeth’. Together these associations explain 6.06% of the variation in ‘age of first tooth’ and 4.76% of the variation in ‘number of teeth’. The identified loci included eight previously unidentified loci, some containing genes known to play a role in tooth and other developmental pathways, including a SNP in the protein-coding region of BMP4 (rs17563, P= 9.080x10−17). Three of these loci, containing the genes HMGA2, AJUBA and ADK, also showed evidence of association with craniofacial distances, particularly those indexing facial width. Our results suggest that the genome-wide association approach is a powerful strategy for detecting variants involved in tooth eruption, and potentially craniofacial growth and more generally organ development

The microaerophilic microbiota of de-novo paediatric inflammatory bowel disease: the BISCUIT study

&lt;p&gt;Introduction: Children presenting for the first time with inflammatory bowel disease (IBD) offer a unique opportunity to study aetiological agents before the confounders of treatment. Microaerophilic bacteria can exploit the ecological niche of the intestinal epithelium; Helicobacter and Campylobacter are previously implicated in IBD pathogenesis. We set out to study these and other microaerophilic bacteria in de-novo paediatric IBD.&lt;/p&gt; &lt;p&gt;Patients and Methods: 100 children undergoing colonoscopy were recruited including 44 treatment naïve de-novo IBD patients and 42 with normal colons. Colonic biopsies were subjected to microaerophilic culture with Gram-negative isolates then identified by sequencing. Biopsies were also PCR screened for the specific microaerophilic bacterial groups: Helicobacteraceae, Campylobacteraceae and Sutterella wadsworthensis.&lt;/p&gt; &lt;p&gt;Results: 129 Gram-negative microaerophilic bacterial isolates were identified from 10 genera. The most frequently cultured was S. wadsworthensis (32 distinct isolates). Unusual Campylobacter were isolated from 8 subjects (including 3 C. concisus, 1 C. curvus, 1 C. lari, 1 C. rectus, 3 C. showae). No Helicobacter were cultured. When comparing IBD vs. normal colon control by PCR the prevalence figures were not significantly different (Helicobacter 11% vs. 12%, p = 1.00; Campylobacter 75% vs. 76%, p = 1.00; S. wadsworthensis 82% vs. 71%, p = 0.312).&lt;/p&gt; &lt;p&gt;Conclusions: This study offers a comprehensive overview of the microaerophilic microbiota of the paediatric colon including at IBD onset. Campylobacter appear to be surprisingly common, are not more strongly associated with IBD and can be isolated from around 8% of paediatric colonic biopsies. S. wadsworthensis appears to be a common commensal. Helicobacter species are relatively rare in the paediatric colon.&lt;/p&gt