bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Dominant Cold-SensitiveOut-ColdMutants ofDrosophila melanogasterHave Novel Missense Mutations in the Voltage-Gated Sodium Channel Geneparalytic
Authors: Lindsay Helen A , Baines Richard , ffrench-Constant Richard , Lilley Kathryn , Jacobs Howard T , O'Dell Kevin M C 
Published: August 2008

AbstractHere we report the molecular characterization of Out-cold (Ocd) mutants of Drosophila melanogaster, which produce a dominant, X-linked, cold-sensitive paralytic phenotype. From its initial 1.5-Mb cytological location within 13F1-16A2, P-element and SNP mapping reduced the Ocd critical region to &lt;100 kb and to six candidate genes: hangover, CG9947, CG4420, eIF2a, Rbp2, and paralytic (para). Complementation testing with para null mutations strongly suggests Ocd and para are allelic, as does gene rescue of Ocd semilethality with a wild-type para transgene. Pesticide resistance and electrophysiological phenotypes of Ocd mutants support this conclusion. The para gene encodes a voltage-gated sodium channel. Sequencing the Ocd lines revealed mutations within highly conserved regions of the para coding sequence, in the transmembrane segment S6 of domain III (I1545M and T1551I), and in the linker between domains III and IV (G1571R), the location of the channel inactivation gate. The G1571R mutation is of particular interest as mutations of the orthologous residue (G1306) in the human skeletal muscle sodium channel gene SCN4A are associated with cases of periodic paralysis and myotonia, including the human cold-sensitive disorder paramyotonia congenita. The mechanisms by which sodium channel mutations cause cold sensitivity are not well understood. Therefore, in the absence of suitable vertebrate models, Ocd provides a system in which genetic, molecular, physiological, and behavioral tools can be exploited to determine mechanisms underlying sodium channel periodic paralyses.
Tissue-Specific Defects Are Caused by Loss of the Drosophila MAN1 LEM Domain Protein
Authors: Pinto Belinda S , Wilmington Shameika R , Hornick Emma E L , Wallrath Lori L , Geyer Pamela K 
Published: August 2008

AbstractThe nuclear lamina represents a protein network required for nuclear structure and function. One family of lamina proteins is defined by an ∼40-aa LAP2, Emerin, and MAN1 (LEM) domain (LEM-D) that binds the nonspecific DNA-binding protein, barrier-to-autointegration factor (BAF). Through interactions with BAF, LEM-D proteins serve as a bridge between chromosomes and the nuclear envelope. Mutations in genes encoding LEM-D proteins cause human laminopathies that are associated with tissue-restricted pathologies. Drosophila has five genes that encode proteins with LEM homology. Using yeast two-hybrid analyses, we demonstrate that four encode proteins that bind Drosophila (d)BAF. In addition to dBAF, dMAN1 associates with lamins, the LEM-D protein Bocksbeutel, and the receptor-regulated Smads, demonstrating parallel protein interactions with vertebrate homologs. P-element mobilization was used to generate null dMAN1 alleles. These mutants showed decreased viability, with surviving adults displaying male sterility, decreased female fertility, wing patterning and positioning defects, flightlessness, and locomotion difficulties that became more severe with age. Increased phospho-Smad staining in dMAN1 mutant wing discs is consistent with a role in transforming growth factor (TGF)-β/bone morphogenic protein (BMP) signaling. The tissue-specific, age-enhanced dMAN1 mutant phenotypes are reminiscent of human laminopathies, suggesting that studies in Drosophila will provide insights into lamina dysfunction associated with disease.
Three α-Subunits of Heterotrimeric G Proteins and an Adenylyl Cyclase Have Distinct Roles in Fruiting Body Development in the Homothallic Fungus Sordaria macrospora
Authors: Kamerewerd Jens , Jansson Malin , Nowrousian Minou , Pöggeler Stefanie , Kück Ulrich 
Published: August 2008

Abstract
Sordaria macrospora, a self-fertile filamentous ascomycete, carries genes encoding three different α-subunits of heterotrimeric G proteins (gsa, G protein Sordaria alpha subunit). We generated knockout strains for all three gsa genes (Δgsa1, Δgsa2, and Δgsa3) as well as all combinations of double mutants. Phenotypic analysis of single and double mutants showed that the genes for Gα-subunits have distinct roles in the sexual life cycle. While single mutants show some reduction of fertility, double mutants Δgsa1Δgsa2 and Δgsa1Δgsa3 are completely sterile. To test whether the pheromone receptors PRE1 and PRE2 mediate signaling via distinct Gα-subunits, two recently generated Δpre strains were crossed with all Δgsa strains. Analyses of the corresponding double mutants revealed that compared to GSA2, GSA1 is a more predominant regulator of a signal transduction cascade downstream of the pheromone receptors and that GSA3 is involved in another signaling pathway that also contributes to fruiting body development and fertility. We further isolated the gene encoding adenylyl cyclase (AC) (sac1) for construction of a knockout strain. Analyses of the three ΔgsaΔsac1 double mutants and one Δgsa2Δgsa3Δsac1 triple mutant indicate that SAC1 acts downstream of GSA3, parallel to a GSA1–GSA2-mediated signaling pathway. In addition, the function of STE12 and PRO41, two presumptive signaling components, was investigated in diverse double mutants lacking those developmental genes in combination with the gsa genes. This analysis was further completed by expression studies of the ste12 and pro41 transcripts in wild-type and mutant strains. From the sum of all our data, we propose a model for how different Gα-subunits interact with pheromone receptors, adenylyl cyclase, and STE12 and thus cooperatively regulate sexual development in S. macrospora.
Genetic Basis of Sex-Specific Color Pattern Variation in Drosophila malerkotliana
Authors: Ng Chen Siang , Hamilton Andrew M , Frank Amanda , Barmina Olga , Kopp Artyom 
Published: August 2008

Abstract
Pigmentation is a rapidly evolving trait that can play important roles in mimicry, sexual selection, thermoregulation, and other adaptive processes in many groups of animals. In Drosophila, pigmentation can differ dramatically among closely related taxa, presenting a good opportunity to dissect the genetic changes underlying species divergence. In this report, we investigate the genetic basis of color pattern variation between two allopatric subspecies of Drosophila malerkotliana, a widespread member of the ananassae species subgroup. In D. malerkotliana malerkotliana, the last three abdominal segments are darkly pigmented in males but not in females, while in D. malerkotliana pallens both sexes lack dark pigmentation. Composite interval mapping in F2 hybrid progeny shows that this difference is largely controlled by three quantitative trait loci (QTL) located on the 2L chromosome arm, which is homologous to the 3R of D. melanogaster (Muller element E). Using highly recombinant introgression strains produced by repeated backcrossing and phenotypic selection, we show that these QTL do not correspond to any of the candidate genes known to be involved in pigment patterning and synthesis in Drosophila. These results, in combination with similar analyses in other Drosophila species, indicate that different genetic and molecular changes are responsible for the evolution of similar phenotypic traits in different lineages. This feature makes Drosophila color patterns a powerful model for investigating how the genetic basis of trait evolution is influenced by the intrinsic organization of regulatory pathways controlling the development of these traits.
UBIQUITIN-SPECIFIC PROTEASE 26 Is Required for Seed Development and the Repression of PHERES1 in Arabidopsis
Authors: Luo Ming , Luo Ming-Zhu , Buzas Diana , Finnegan Jean , Helliwell Chris , Dennis Elizabeth S , Peacock W J , Chaudhury Abed 
Published: August 2008

Abstract
The Arabidopsis mutant Atubp26 initiates autonomous endosperm at a frequency of ∼1% in the absence of fertilization and develops arrested seeds at a frequency of ∼65% when self-pollinated. These phenotypes are similar to those of the FERTILIZATION INDEPENDENT SEED (FIS) class mutants, mea, fis2, fie, and Atmsi1, which also show development of the central cell into endosperm in the absence of fertilization and arrest of the embryo following fertilization. Atubp26 results from a T-DNA insertion in the UBIQUITIN-SPECIFIC PROTEASE gene AtUBP26, which catalyzes deubiquitination of histone H2B and is required for heterochromatin silencing. The paternal copy of AtUBP26 is able to complement the loss of function of the maternal copy in postfertilization seed development. This contrasts to the fis class mutants where the paternal FIS copy does not rescue aborted seeds. As in the fis class mutants, the Polycomb group (PcG) complex target gene PHERES1 (PHE1) is expressed at higher levels in Atubp26 ovules than in wild type; there is a lower level of H3K27me3 at the PHE1 locus. The phenotypes suggest that AtUBP26 is required for normal seed development and the repression of PHE1.
The Pleiotropic Phenotype of Apc Mutations in the Mouse: Allele Specificity and Effects of the Genetic Background
Authors: Halberg Richard B , Chen Xiaodi , Amos-Landgraf James M , White Alanna , Rasmussen Kristin , Clipson Linda , Pasch Cheri , Sullivan Ruth , Pitot Henry C , Dove William F 
Published: August 2008

Abstract
Familial adenomatous polyposis (FAP) is a human cancer syndrome characterized by the development of hundreds to thousands of colonic polyps and extracolonic lesions including desmoid fibromas, osteomas, epidermoid cysts, and congenital hypertrophy of the pigmented retinal epithelium. Afflicted individuals are heterozygous for mutations in the APC gene. Detailed investigations of mice heterozygous for mutations in the ortholog Apc have shown that other genetic factors strongly influence the phenotype. Here we report qualitative and quantitative modifications of the phenotype of Apc mutants as a function of three genetic variables: Apc allele, p53 allele, and genetic background. We have found major differences between the Apc alleles Min and 1638N in multiplicity and regionality of intestinal tumors, as well as in incidence of extracolonic lesions. By contrast, Min mice homozygous for either of two different knockout alleles of p53 show similar phenotypic effects. These studies illustrate the classic principle that functional genetics is enriched by assessing penetrance and expressivity with allelic series. The mouse permits study of an allelic gene series on multiple genetic backgrounds, thereby leading to a better understanding of gene action in a range of biological processes.
Safe Use of Radioisotopes
Authors: Meisenhelder Jill , Bursik Steve 
Published: August 2008

AbstractThe pursuit of scientific knowledge has been considerably advanced by the use of biochemical molecules that incorporate radioisotopes at specific sites. The fate of these labeled molecules, and/or the radiolabeled products that result from biochemical reactions in which the parent molecule was involved, can be traced using a variety of instruments that detect radioactivity. This appendix begins with a discussion of the principles of radioactivity in order to provide the reader/user with knowledge on which to base a common sense approach to the safe use of isotopes. The characteristics of isotopes most commonly used in a molecular biology laboratory are then detailed, as well as the safety precautions and monitoring methods peculiar to each one. Detection and imaging methods used in experimental analysis are reviewed. Finally, an outline of an orderly response to a spill of radioactive material is presented. Curr. Protoc. Toxicol. 37:A.1A.1‐A.1A.18. © 2008 by John Wiley & Sons, Inc.
ErbB2 Transgenic Mice: A Tool for Investigation of the Immune Prevention and Treatment of Mammary Carcinomas
Authors: Quaglino Elena , Mastini Cristina , Forni Guido , Cavallo Federica 
Published: August 2008

AbstractThe epidermal growth factor receptor belongs to a superfamily of receptor tyrosine kinases (RTK) that includes ErbB2. ErbB2 is involved in normal physiological processes, such as embryogenesis, cell proliferation, differentiation, adhesion motility, and apoptosis, while its malfunction or overexpression is responsible for development defects, diabetes, and cancer. The human ortholog of ErbB2 is referred as Her‐2 (human ErbB2) while the rat ortholog is referred as neu (rat ErbB2). As ErbB2 is directly involved in carcinogenesis, mice transgenic for the rat neu oncogene allow straightforward assessment of the ability of drugs and vaccines to inhibit the progression of neu‐driven cancer. Information from this model may provide indications on the efficacy of similar treatments in patients. This commentary provides key information regarding the use of these transgenic mouse models for evaluation of the efficacy of anti‐tumor strategies. Curr. Protoc. Immunol. 82:20.9.1‐20.9.10. © 2008 by John Wiley & Sons, Inc.
Characterization of Heat and Momentum Transfer in Sintered Metal Foams
Authors: Reutter O. , Sauerhering J. , Fend T. , Pitz‐Paal R. , Angel S. 
Published: August 2008

AbstractIn this study, metal foams made by the Slip Reaction Foam Sintering (SRFS)‐process are investigated concerning their thermophysical and permeability properties. Since the foam is to be applied as a functional and structural element in the effusion air cooling system of a stationary gas turbine combustion chamber, these properties are of major interest for the calculation of the temperature distribution inside the combustion chamber walls, which may be critical for the employed materials. Experimental set‐ups are presented, which are used to determine permeability, the volumetric heat transfer coefficient and the effective thermal conductivity. The results are presented for a wide range of foam materials. Porosity as well as the basic metal powder and the manufacturing parameters are varied. The influence of these parameters on the measured quantities is discussed. Thermal conductivity data are determined at temperatures of up to 1200 K. The obtained volumetric heat transfer coefficients are transferred to Nusselt–Reynolds plots, which allow generalization to the high temperature and high pressure regime. Correlations between the heat transfer properties and the permeability data are made. Using the acquired experimental data, a proposal is made for the calculation of the inner surface temperature of the combustion chamber as well as the temperature distribution inside the chamber wall, which consists of a structural element, the metal foam and a thermal barrier coating, equipped with laser drilled micro‐holes.
Photooxygenation Catalysis with a Polyol‐Decorated Disc‐Shaped Porphyrin Sensitizer: Shell‐Recognition Effects
Authors: Griesbeck Axel G. , Schäfer Mathias , Uhlig Johannes 
Published: August 2008

AbstractPolar meso‐tetraarylporphyrins 2–4 were synthesized from tetrakis‐4‐hydroxyphenylporphyrin 1 as the central building block by consecutive base‐induced reactions with glycidol. The decorating units form a polar hydrogen‐bonded shell around the sensitizer core which is proposed as the binding site for polar substrates in photocatalyzed oxygenation reactions. As substrate, the polarity‐sensor mesitylol (5) was applied and the reaction constrained in a polystyrene matrix. Increasing shell dimensions lead to increased diastereoselectivities for the allylic hydroperoxides 6 and thus clearly demonstrate the concept of shell‐induced substrate stereoselectivity in singlet oxygen reactions.
Enantioselective Organocatalytic Reactions of 4‐Hydroxycoumarin and 4‐Hydroxypyrone with α,β‐Unsaturated Aldehydes – An Efficient Michael Addition‐Acetalization Cascade to Chromenones, Quinolinones and Pyranones
Authors: Rueping Magnus , Merino Estíbaliz , Sugiono Erli 
Published: August 2008

AbstractAn efficient, organocatalytic enantioselective addition‐cyclization reaction of cyclic 1,3‐dicarbonyl compounds with different α,β‐unsaturated aldehydes has been developed. The diarylprolinol ether‐catalyzed reaction cascade provides a variety of chromenones, quinolinones and pyranones in good yields and with excellent enantioselectivities.
Differential association between MAOA, ADHD and neuropsychological functioning in boys and girls
Authors: Rommelse Nanda N.J. , Altink Marieke E. , Arias‐Vásquez Alejandro , Buschgens Cathelijne J.M. , Fliers Ellen , Faraone Stephen V. , Buitelaar Jan K. , Sergeant Joseph A. , Oosterlaan Jaap , Franke Barbara 
Published: August 2008

AbstractAttention‐deficit/hyperactivity disorder (ADHD) is more common in boys than in girls. It has been hypothesized that this sex difference might be related to genes on the X‐chromosome, like Monoamine Oxidase A (MAOA). Almost all studies on the role of MAOA in ADHD have focused predominantly on boys, making it unknown whether MAOA also has an effect on ADHD in girls, and few studies have investigated the relationship between MAOA and neuropsychological functioning, yet this may provide insight into the pathways leading from genotype to phenotype. The current study set out to examine the relationship between MAOA, ADHD, and neuropsychological functioning in both boys (265 boys with ADHD and 89 male non‐affected siblings) and girls (85 girls with ADHD and 106 female non‐affected siblings). A haplotype was used based on three single nucleotide polymorphisms (SNPs) (rs12843268, rs3027400, and rs1137070). Two haplotypes (GGC and ATT) captured 97% of the genetic variance in the investigated MAOA SNPs. The ATT haplotype was more common in non‐affected siblings (P = 0.025), conferring a protective effect for ADHD in both boys and girls. The target and direction of the MAOA effect on neuropsychological functioning was different in boys and girls: The ATT haplotype was associated with poorer motor control in boys (P = 0.002), but with better visuo‐spatial working memory in girls (P = 0.01). These findings suggest that the genetic and neuropsychological mechanisms underlying ADHD may be different in boys and girls and underline the importance of taking into account sex effects when studying ADHD. © 2008 Wiley‐Liss, Inc.
Porphyrine mit metallorganischen Gruppen: Synthese und Anwendungen
Authors: Suijkerbuijk Bart M. J. M. , Klein Gebbink Robertus J. M. 
Published: August 2008

AbstractDie Koordinationschemie der Porphyrine dreht sich vornehmlich um den Einbau von Metallionen unterschiedlicher Ladung und Größe in den Tetrapyrrolkern, um Metalloporphyrine mit neuen Eigenschaften zu erhalten. Eine Organometallchemie der Porphyrine muss sich aber nicht zwangsläufig auf das im Porphyrinkern gebundene Metallion beschränken, sondern sie kann sich auch auf die Molekülperipherie erstrecken: Der Porphyrinmakrocyclus kann durch direkte Metallierung in meso‐ oder β‐Stellung modifiziert oder aber mit Liganden verknüpft werden, die anschließend eine Metallierung eingehen. Dieser Aufsatz beschreibt Synthesestrategien für Porphyrine mit Metall‐Kohlenstoff‐Bindungen in der Molekülperipherie. Die beachtenswerten Ergebnisse, die hierbei erzielt wurden, heben die Bedeutung dieses Forschungsgebiets hervor und zeigen Perspektiven auf.
Phase behavior of blends containing amorphous poly(resorcinol phthalate‐block‐carbonate) and semicrystalline polyesters
Authors: Kim Sung Dug , Chakravarti Shreyas , Tian Jun 
Published: August 2008

AbstractThe phase behavior of poly(resorcinol phthalate‐block‐carbonate) (RPC) with engineering polyesters was investigated by using differential scanning calorimeter (DSC) and dynamic mechanical analysis. RPC was found to form miscible blends with poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT), and poly(cyclohexylmethylene terephthalate) (PCT), but was partially miscible with poly(1,4‐cyclohexanedimethylene‐1,4‐cyclohexanedicarboxylate) (PCCD) in the melt state and below the melting temperature (Tm). The degree of melting‐point depression indicates that the RPC is most miscible with PCT followed by PET and then PBT. Furthermore, with the help of empirical DSC data and the Nishi–Wang equation, the interaction parameters between RPC and PET, PBT, and PCT were quantified to be −0.36, −0.33, and −0.54, respectively. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Vapor–liquid equilibria for polymer solutions through a group‐contribution method: Chain‐length dependence
Authors: Lee Seung Seok , Sun Yang Kook , Bae Young Chan 
Published: August 2008

AbstractA new group‐contribution model based on the modified double‐lattice theory considering chain‐length dependence of the universal parameters was developed and applied to describe the vapor–liquid equilibria of polymer solutions. The proposed model includes the combinatorial energy contribution that is responsible for the revised Flory–Huggins entropy of mixing, the van der Waals energy contribution from dispersion and polar forces, and the specific energy contribution from hydrogen bonding. The quantitative description according to the proposed model was in good agreement with experimentally observed solvent activities of polymer solutions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Role of Intraflagellar Transport and Primary Cilia in Skeletal Development
Authors: Serra Rosa 
Published: August 2008

AbstractPrimary cilia are nonmotile microtubule‐based appendages extending from the surface of almost all vertebrate cells. The process of intraflagellar transport (IFT) is responsible for building and maintaining the structure and function of primary cilia. Disruption of Kif3a, a component of the Kinesin‐II motor complex, disables anterograde IFT and leads to failure in the formation and maintenance of cilia. Likewise, the absence of IFT88/Tg737/Polaris, a core component of the IFT particle, results in the loss of cilia. Although primary cilia were described on chondrocytes almost 40 years ago, only recently has the functional significance of IFT and cilia in skeletal development been uncovered through the use of mouse models containing mutations or deletions in genes required to make and maintain cilia. Together, the results indicate that primary cilia/IFT are involved in coordinating multiple signaling pathways within the skeleton. Anat Rec, 291:1049–1061, 2008. © 2008 Wiley‐Liss, Inc.
The Primary Cilium of Connective Tissue Cells: Imaging by Multiphoton Microscopy
Authors: Donnelly Eve , Williams Rebecca , Farnum Cornelia 
Published: August 2008

AbstractAlthough the role of the primary cilium as a sensory organelle in epithelial cells has been elucidated significantly over the past decade, the function of primary cilia in connective tissue cells has been studied less extensively. Primary cilia have been implicated as mechanotransducers in connective tissues, but the mechanisms by which the cells sense loads and convert them to biochemical signals for tissue formation and adaptation are poorly understood. Before hypotheses regarding the function of the primary cilium in connective tissue cells can be tested, methods for quantitation of incidence as well as three‐dimensional visualization of primary cilia with respect to the extracellular matrix (ECM) are needed. The objective of this study was to develop a rapid method for visualizing primary cilia in their native ECM in a wide range of connective tissues. Whole‐mount immunohistochemical and multiphoton microscopy techniques were developed to simultaneously image primary cilia, cell nuclei, and collagen and their relationships to each other in situ. Axonemes of primary cilia projecting into the ECM were successfully visualized in thick sections of growth plate cartilage, tendon, ligament, meniscus, intervertebral disc, and perichondrium. These methodologies will allow analysis of the incidence and three‐dimensional orientation of primary cilia and enable investigation of the role of primary cilia in normal and pathological growth and adaptation in a variety of musculoskeletal tissues. Anat Rec, 291:1062–1073, 2008. © 2008 Wiley‐Liss, Inc.