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Abstract: Prohibitin (PHB) is a ubiquitously expressed and evolutionarily conserved mitochondrial protein with multiple functions. We have recently shown that PHB up‐regulation offers robust protection against neuronal injury in models of cerebral ischemia in vitro and in vivo, but the mechanism by which PHB affords neuroprotection remains to be elucidated. Here, we manipulated PHB expression in PC12 neural cells to investigate its impact on mitochondrial function and the mechanisms whereby it protects cells exposed to oxidative stress. PHB over‐expression promoted cell survival, whereas PHB down‐regulation diminished cell viability. Functionally, manipulation of PHB levels did not affect basal mitochondrial respiration, but it increased spare respiratory capacity. Moreover, PHB over‐expression preserved mitochondrial respiratory function of cells exposed to oxidative stress. Preserved respiratory capacity in differentiated PHB over‐expressing cells exposed to oxidative stress was associated with an elongated mitochondrial morphology, whereas PHB down‐regulation enhanced fragmentation. Mitochondrial complex I oxidative degradation was attenuated by PHB over‐expression and increased in PHB knockdown cells. Changes in complex I degradation were associated with alterations of respiratory chain supercomplexes. Furthermore, we showed that PHB directly interacts with cardiolipin and that down‐regulation of PHB results in loss of cardiolipin in mitochondria, which may contribute to destabilizing respiratory chain supercomplexes. Taken together, these data demonstrate that PHB modulates mitochondrial integrity and bioenergetics under oxidative stress, and suggest that the protective effect of PHB is mediated by stabilization of the mitochondrial respiratory machinery and its functional capacity, by the regulation of cardiolipin content. Open Data: Materials are available on https://cos.io/our-services/open-science-badges/ https://osf.io/93n6m/ [ABSTRACT FROM AUTHOR]

The molecular mechanisms underlying congenital long QT syndrome (LQTS) are now beginning to be understood. New insights into the etiology and therapeutic strategies are emerging from heterologous expression studies of LQTS-linked mutant proteins, as well as inducible pluripotent stem cell derived cardiomyocytes (iPSC-CMs) from LQTS patients. This review focuses on the major molecular mechanism that underlies LQTS type 2 (LQT2). LQT2 is caused by loss of function (LOF) mutations in KCNH2 (also known as the human Ether-à-go-go-Related Gene or hERG ). Most LQT2-linked mutations are missense mutations and functional studies suggest that ~90% of them disrupt the intracellular transport (trafficking) of KCNH2 -encoded Kv11.1 proteins to the cell membrane. Trafficking deficient LQT2 mutations disrupt Kv11.1 protein folding and misfolded Kv11.1 proteins are retained in the endoplasmic reticulum (ER) until they are degraded in the ER associated degradation pathway (ERAD). This review focuses on the quality control mechanisms in the ER that contribute to the folding and ERAD of Kv11.1 proteins; the mechanism for ER export of Kv11.1 proteins in the secretory pathway; different subclasses of trafficking deficient LQT2 mutations; and strategies being developed to mitigate or correct trafficking deficient LQT2-related phenotypes. [ABSTRACT FROM AUTHOR]

Landscape features exist at multiple spatial and temporal scales, and these naturally affect spatial genetic structure and our ability to make inferences about gene flow. This article discusses how decisions about sampling of genotypes (including choices about analytical methods and genetic markers) should be driven by the scale of spatial genetic structure, the time frame that landscape features have existed in their current state, and all aspects of a species’ life history. Researchers should use caution when making inferences about gene flow, especially when the spatial extent of the study area is limited. The scale of sampling of the landscape introduces different features that may affect gene flow. Sampling grain should be smaller than the average home-range size or dispersal distance of the study organism and, for raster data, existing research suggests that simplifying the thematic resolution into discrete classes may result in low power to detect effects on gene flow. Therefore, the methods used to characterize the landscape between sampling sites may be a primary determinant for the spatial scale at which analytical results are applicable, and the use of only one sampling scale for a particular statistical method may lead researchers to overlook important factors affecting gene flow. The particular analytical technique used to correlate landscape data and genetic data may also influence results; common landscape-genetic methods may not be suitable for all study systems, particularly when the rate of landscape change is faster than can be resolved by common molecular markers. [ABSTRACT FROM AUTHOR]

Informally gathered species lists are a potential source of data for conservation biology, but most remain unused because of questions of reliability and statistical issues. We applied two alternative analytical methods (contingency tests and occupancy modeling) to a 35-year data set (1973–2007) to test hypotheses about local bird extinction. We compiled data from bird lists collected by expert amateurs and professional scientists in a 2-km2 fragment of lowland tropical forest in coastal Ecuador. We tested the effects of the following on local extinction: trophic level, sociality, foraging specialization, light tolerance, geographical range area, and biogeographic source. First we assessed extinction on the basis of the number of years in which a species was not detected on the site and used contingency tests with each factor to compare the frequency of expected and observed extinction events among different species categories. Then we defined four multiyear periods that reflected different stages of deforestation and isolation of the study site and used occupancy modeling to test extinction hypotheses singly and in combination. Both types of analyses supported the biogeographic source hypothesis and the species-range hypothesis as causes of extinction; however, occupancy modeling indicated the model incorporating all factors except foraging specialization best fit the data. [ABSTRACT FROM AUTHOR]

Reconstituted cell-free (CF) protein expression systems hold the promise of overcoming the traditional barriers associated with in vivo systems. This is particularly true for membrane proteins, which are often cytotoxic and due to the nature of the membrane, difficult to work with. To evaluate the potential of cell-free expression, we cloned 120 membrane proteins from E. coli and compared their expression profiles in both an E. coli in vivo system and an E. coli-derived cell-free system. Our results indicate CF is a more robust system and we were able to express 63% of the targets in CF, compared to 44% in vivo. To benchmark the quality of CF produced protein, five target membrane proteins were purified and their homogeneity assayed by gel filtration chromatography. Finally, to demonstrate the ease of amino acid labeling with CF, a novel membrane protein was substituted with selenomethionine, purified, and shown to have 100% incorporation of the unnatural amino acid. We conclude that CF is a novel, robust expression system capable of expressing more proteins than an in vivo system and suitable for production of membrane proteins at the milligram level. [ABSTRACT FROM AUTHOR]

I tested six microsatellite DNA primer pairs developed for the massasauga rattlesnake ( Sistrurus catenatus) on a sample population of the timber rattlesnake ( Crotalus horridus). It had been speculated in a previous publication that cross-species amplification would not be worthwhile across the two rattlesnake genera. However, for this primer set (the only one currently published for the genus Sistrurus), successful amplification at each locus was accomplished for all loci with an annealing temperature of 57 °C and locus-specific buffer conditions. Each locus was polymorphic, with the number of alleles per locus ranging from two to 12. Significant heterozygote deficits were detected for three loci (Scu01, Scu05 and Scu07 ). For Scu01, all individuals were homozygous for the same allele except one female who was homozygous for a different allele. This same female was also homozygous for a rare allele at Scu07. When this female was removed from the data set, the number of observed heterozygotes at Scu01 and Scu07 did not differ significantly from random expectations. However, a large heterozygote deficit persisted at Scu05 (despite subsampling), suggesting that this locus may not be useful for population genetic studies of timber rattlesnakes. Despite some limitations, this set of primers may be a useful complement to those already developed for the genus Crotalus. Moreover, the results of this study seem to provide new justification for further studies of cross-species amplification of microsatellite loci across the two rattlesnake genera. [ABSTRACT FROM AUTHOR]

A major technology break in snake biology was the publication of surgical protocols for implanting radiotransmitters in the body cavities of snakes. While many researchers have reported using some variant of these protocols successfully, protocol details often vary from study to study and best-practice procedures are not easily determinable given the variety of circumstances over which studies occur. Although professional society standards and federal regulations make explicit recommendations about this surgical procedure, some of the nonstandard techniques recommended for this protocol may raise the eyebrows of institutional animal care and use committees. In this commentary we discuss regulatory and logistical aspects of the intracoelmic radiotransmitter implant procedure for snakes, and we provide a pragmatic framework for choosing among surgical variables. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Addition of α-Lithiated Nitriles to Azaheterocycles" by C. Anderson, J. Moreno and S. Hadida, published in the periodical "Synlett" in 2014.

The article discusses research on the putative stem cells found in the regenerated tissues through markers related to mesenchymal stem cells. It references the study "Putative Stem Cells in Regenerating Human Periodontium," by N. H. et al, published in the July 4, 2008 issue of "Journal of Periodontal Research." The researchers explained that the presence of cells with periodontal ligament (PDL) stem cells qualities in the tissue taken from the so-called guided tissue regeneration (GTR)-treated defects indicates the role of stem cells in healing.

Primary neurogenic tumors of the heart are extremely uncommon. We report the resection of a benign primary schwannoma of the right atrium found incidentally during an aortic valve replacement. , (© 2010 Wiley Periodicals, Inc.)