bluuebunny/crossref_metadata_2025 huggingface dataset:
SIP1 protein protects cells from DNA damage-induced apoptosis and has independent prognostic value in bladder cancer
Authors: Sayan A. Emre , Griffiths Thomas R. , Pal Raj , Browne Gareth J. , Ruddick Andrew , Yagci Tamer , Edwards Richard , Mayer Nick J. , Qazi Hasan , Goyal Sandeep , Fernandez Serena , Straatman Kees , Jones George D. D. , Bowman Karen J. , Colquhoun Alexandra , Mellon J. Kilian , Kriajevska Marina , Tulchinsky Eugene
Published: August 2009

The epithelial-mesenchymal transition (EMT) contributes to cancer metastasis. Two ZEB family members, ZEB1 and ZEB2(SIP1), inhibit transcription of the E-cadherin gene and induce EMT in vitro. However, their relevance to human cancer is insufficiently studied. Here, we performed a comparative study of SIP1 and ZEB1 proteins in cancer cell lines and in one form of human malignancy, carcinoma of the bladder. Whereas ZEB1 protein was expressed in all E-cadherin-negative carcinoma cell lines, being in part responsible for the high motility of bladder cancer cells, SIP1 was hardly ever detectable in carcinoma cells in culture. However, SIP1 represented an independent factor of poor prognosis (
P
= 0.005) in a series of bladder cancer specimens obtained from patients treated with radiotherapy. In contrast, ZEB1 was rarely expressed in tumor tissues; and E-cadherin status did not correlate with the patients' survival. SIP1 protected cells from UV- and cisplatin-induced apoptosis in vitro but had no effect on the level of DNA damage. The anti-apoptotic effect of SIP1 was independent of either cell cycle arrest or loss of cell-cell adhesion and was associated with reduced phosphorylation of ATM/ATR targets in UV-treated cells. The prognostic value of SIP1 and its role in DNA damage response establish a link between genetic instability and metastasis and suggest a potential importance for this protein as a therapeutic target. In addition, we conclude that the nature of an EMT pathway rather than the deregulation of E-cadherin per se is critical for the progression of the disease and patients' survival.
FunctionalCRHvariation increases stress-induced alcohol consumption in primates
Authors: Barr Christina S. , Dvoskin Rachel L. , Gupte Manisha , Sommer Wolfgang , Sun Hui , Schwandt Melanie L. , Lindell Stephen G. , Kasckow John W. , Suomi Stephen J. , Goldman David , Higley J. Dee , Heilig Markus
Published: August 2009

Corticotropin-releasing factor (CRF), encoded by theCRHgene, is a key integrator of stress responses, and, as such,CRHgene variation may contribute to individual differences in susceptibility to stress-related pathology. In rhesus macaques, a single nucleotide polymorphism (SNP) is found within theCRHpromoter (−248C→ T). Here, we assessed whether this variant influenced stress responding and, because increased CRF system activity drives alcohol drinking in rodents, we examined whether it predicted voluntary alcohol consumption as a function of prior stress exposure. Using a hypothalamic nuclear extract, we showed that the −248 T allele resulted in increased DNA protein interactions relative to the C allele. In vitro, the T allele resulted inCRHpromoter activity that was higher following both stimulation with forskolin and treatment with dexamethasone. Endocrine and behavioral responses to social separation stress (release of ACTH and cortisol, and suppression of environmental exploration, respectively) were higher among carriers of the T allele, particularly among those exposed to early adversity in the form of peer rearing. We also found that T allele carriers with a history of early life adversity consumed more alcohol in a limited-access paradigm. Our data suggest thatCRHpromoter variation that confers increased stress reactivity increases the risk for alcohol use disorders in stress-exposed individuals.
Heme oxygenase-1 affords protection against noncerebral forms of severe malaria
Authors: Seixas Elsa , Gozzelino Raffaella , Chora Ângelo , Ferreira Ana , Silva Gabriela , Larsen Rasmus , Rebelo Sofia , Penido Carmen , Smith Neal R. , Coutinho Antonio , Soares Miguel P.
Published: August 2009

Infection byPlasmodium, the causative agent of malaria, is associated with hemolysis and therefore with release of hemoglobin from RBC. Under inflammatory conditions, cell-free hemoglobin can be oxidized, releasing its heme prosthetic groups and producing deleterious free heme. Here we demonstrate that survival of aPlasmodium-infected host relies strictly on its ability to prevent the cytotoxic effects of free heme via the expression of the heme-catabolyzing enzyme heme oxygenase-1 (HO-1; encoded by theHmox1gene). When infected withPlasmodium chabaudi chabaudi(Pcc), wild-type (Hmox1+/+) BALB/c mice resolved infection and restored homeostasis thereafter (0% lethality). In contrast, HO-1 deficient (Hmox1−/−) BALB/c mice developed a lethal form of hepatic failure (100% lethality), similar to the one occurring inPcc-infected DBA/2 mice (75% lethality). Expression of HO-1 suppresses the pro-oxidant effects of free heme, preventing it from sensitizing hepatocytes to undergo TNF-mediated programmed cell death by apoptosis. This cytoprotective effect, which inhibits the development of hepatic failure inPcc-infected mice without interfering with pathogen burden, is mimicked by pharmacological antioxidants such as N-acetylcysteine (NAC). When administered therapeutically, i.e., afterPccinfection, NAC suppressed the development of hepatic failure inPcc-infected DBA/2 mice (0% lethality), without interfering with pathogen burden. In conclusion, we describe a mechanism of host defense againstPlasmodiuminfection, based on tissue cytoprotection against free heme and limiting disease severity irrespectively of parasite burden.
Geological sulfur isotopes indicate elevated OCS in the Archean atmosphere, solving faint young sun paradox
Authors: Ueno Yuichiro , Johnson Matthew S. , Danielache Sebastian O. , Eskebjerg Carsten , Pandey Antra , Yoshida Naohiro
Published: August 2009

Distributions of sulfur isotopes in geological samples would provide a record of atmospheric composition if the mechanism producing the isotope effects could be described quantitatively. We determined the UV absorption spectra of
32
SO
2
,
33
SO
2
, and
34
SO
2
and use them to interpret the geological record. The calculated isotopic fractionation factors for SO
2
photolysis give mass independent distributions that are highly sensitive to the atmospheric concentrations of O
2
, O
3
, CO
2
, H
2
O, CS
2
, NH
3
, N
2
O, H
2
S, OCS, and SO
2
itself. Various UV-shielding scenarios are considered and we conclude that the negative Δ
33
S observed in the Archean sulfate deposits can only be explained by OCS shielding. Of relevant Archean gases, OCS has the unique ability to prevent SO
2
photolysis by sunlight at λ >202 nm. Scenarios run using a photochemical box model show that ppm levels of OCS will accumulate in a CO-rich, reducing Archean atmosphere. The radiative forcing, due to this level of OCS, is able to resolve the faint young sun paradox. Further, the decline of atmospheric OCS may have caused the late Archean glaciation.
Vaccinia virus inoculation in sites of allergic skin inflammation elicits a vigorous cutaneous IL-17 response
Authors: Oyoshi Michiko K. , Elkhal Abdallah , Kumar Lalit , Scott Jordan E. , Koduru Suresh , He Rui , Leung Donald Y. M. , Howell Michael D. , Oettgen Hans C. , Murphy George F. , Geha Raif S.
Published: August 2009

Eczema vaccinatum (EV) is a complication of smallpox vaccination occurring in patients with atopic dermatitis. In affected individuals, vaccinia virus (VV) spreads through the skin, resulting in large primary lesions and satellite lesions, and infects internal organs. BALB/c mice inoculated with VV at sites of Th2-biased allergic skin inflammation elicited by epicutaneous ovalbumin (OVA) sensitization exhibited larger primary lesions that were erosive, more satellite lesions, and higher viral loads in skin and internal organs than mice inoculated in saline-exposed skin, unsensitized skin, or skin sites with Th1-dominant inflammation. VV inoculation in OVA-sensitized skin induced marked local expression of IL-17 transcripts and massive neutrophil infiltration compared to VV inoculation in saline-exposed skin. Treatment with anti-IL-17 decreased the size of primary lesions, numbers of satellite lesions, and viral loads. Addition of IL-17 promoted VV replication in skin explants. These results suggest that IL-17 may be a potential therapeutic target in EV.
The origin and evolution of fragrance in rice (
Oryza sativa
L.)
Authors: Kovach Michael J. , Calingacion Mariafe N. , Fitzgerald Melissa A. , McCouch Susan R.
Published: August 2009

Fragrance in the grain is one of the most highly valued grain quality traits in rice, yet the origin and evolution of the betaine aldehyde dehydrogenase gene (
BADH2
) underlying this trait remains unclear. In this study, we identify eight putatively nonfunctional alleles of the
BADH2
gene and show that these alleles have distinct geographic and genetic origins. Despite multiple origins of the fragrance trait, a single allele,
badh2.1
, is the predominant allele in virtually all fragrant rice varieties today, including the widely recognized Basmati and Jasmine types. Haplotype analysis allowed us to establish a single origin of the
badh2.1
allele within the
Japonica
varietal group and demonstrate the introgression of this allele from
Japonica
to
Indica
. Basmati-like accessions were nearly identical to the ancestral
Japonica
haplotype across a 5.3-Mb region flanking
BADH2
regardless of their fragrance phenotype, demonstrating a close evolutionary relationship between Basmati varieties and the
Japonica
gene pool. These results clarify the relationships among fragrant rice varieties and challenge the traditional assumption that the fragrance trait arose in the
Indica
varietal group.
The intrinsic dynamics of enzymes plays a dominant role in determining the structural changes induced upon inhibitor binding
Authors: Bakan Ahmet , Bahar Ivet
Published: August 2009

The conformational flexibility of target proteins continues to be a major challenge in accurate modeling of protein–inhibitor interactions. A fundamental issue, yet to be clarified, is whether the observed conformational changes are controlled by the protein or induced by the inhibitor. Although the concept of induced fit has been widely adopted for describing the structural changes that accompany ligand binding, there is growing evidence in support of the dominance of proteins' intrinsic dynamics which has been evolutionarily optimized to accommodate its functional interactions. The wealth of structural data for target proteins in the presence of different ligands now permits us to make a critical assessment of the balance between these two effects in selecting the bound forms. We focused on three widely studied drug targets, HIV-1 reverse transcriptase, p38 MAP kinase, and cyclin-dependent kinase 2. A total of 292 structures determined for these enzymes in the presence of different inhibitors and unbound form permitted us to perform an extensive comparative analysis of the conformational space accessed upon ligand binding, and its relation to the intrinsic dynamics before ligand binding as predicted by elastic network model analysis. Our results show that the ligand selects the conformer that best matches its structural and dynamic properties among the conformers intrinsically accessible to the protein in the unliganded form. The results suggest that simple but robust rules encoded in the protein structure play a dominant role in predefining the mechanisms of ligand binding, which may be advantageously exploited in designing inhibitors.
The Q motif of a viral packaging motor governs its force generation and communicates ATP recognition to DNA interaction
Authors: Tsay James M. , Sippy Jean , Feiss Michael , Smith Douglas E.
Published: August 2009

A key step in the assembly of many viruses is the packaging of DNA into preformed procapsids by an ATP-powered molecular motor. To shed light on the motor mechanism we used single-molecule optical tweezers measurements to study the effect of mutations in the large terminase subunit in bacteriophage λ on packaging motor dynamics. A mutation, K84A, in the putative ATPase domain driving DNA translocation was found to decrease motor velocity by ≈40% but did not change the force dependence or decrease processivity substantially. These findings support the hypothesis that a deviant “Walker A-like” phosphate-binding motif lies adjacent to residue 84. Another mutation, Y46F, was also found to decrease motor velocity by ≈40% but also increase slipping during DNA translocation by >10-fold. These findings support the hypothesis that viral DNA packaging motors contain an adenine-binding motif that regulates ATP hydrolysis and substrate affinity analogous to the “Q motif” recently identified in DEAD-box RNA helicases. We also find impaired force generation for the Y46F mutant, which shows that the Q motif plays an important role in determining the power and efficiency of the packaging motor.
Unexpected electron transfer mechanism upon AdoMet cleavage in radical SAM proteins
Authors: Nicolet Yvain , Amara Patricia , Mouesca Jean-Marie , Fontecilla-Camps Juan C.
Published: August 2009

Radical
S
-adenosine-L-methionine (SAM or AdoMet) proteins are involved in chemically difficult reactions including the synthesis of cofactors, the generation of protein radicals, and the maturation of complex organometallic catalytic sites. In the first and common step of the reaction, a conserved [Fe
4
S
4
] cluster donates an electron to perform the reductive cleavage of AdoMet into methionine and a reactive radical 5′-dA· species. The latter extracts a hydrogen atom from substrate eliciting one of the about 40 reactions so far characterized for this family of proteins. It has been suggested that the radical-generating mechanism differs depending on whether AdoMet is a cofactor or a substrate. It has also been speculated that electron transfer from the [Fe
4
S
4
] cluster to AdoMet is sulfur-based. Here we have used protein crystallography and theoretical calculations to show that regardless whether AdoMet serves as a cofactor or a substrate, the 5′-dA· generating mechanism should be common to the radical SAM proteins studied so far, and that electron transfer is mediated by a unique Fe from the conserved [Fe
4
S
4
] cluster. This unusual electron transfer is determined by the sulfonium ion in AdoMet.
Macroevolutionary chemical escalation in an ancient plant–herbivore arms race
Authors: Becerra Judith X. , Noge Koji , Venable D. Lawrence
Published: August 2009

A central paradigm in the field of plant–herbivore interactions is that the diversity and complexity of secondary compounds in plants have intensified over evolutionary time, resulting in the great variety of secondary products that currently exists. Unfortunately, testing of this proposal has been very limited. We analyzed the volatile chemistry of 70 species of the tropical plant genus
Bursera
and used a molecular phylogeny to test whether the species' chemical diversity or complexity have escalated. The results confirm that as new species diverged over time they tended to be armed not only with more compounds/species, but also with compounds that could potentially be more difficult for herbivores to adapt to because they belong to an increasing variety of chemical pathways. Overall chemical diversity in the genus also increased, but not as fast as species diversity, possibly because of allopatric species gaining improved defense with compounds that are new locally, but already in existence elsewhere.
Protein kinases mediate ligand-independent derepression of sumoylated progesterone receptors in breast cancer cells
Authors: Daniel Andrea R. , Lange Carol A.
Published: August 2009

In advanced breast tumors, protein kinases are upregulated and steroid hormone receptors often function independently of ligand. Herein, we explored mechanisms of ligand-independent progesterone receptor (PR) activity. We showed previously that growth factor-induced phosphorylation of PR Ser-294 blocks PR Lys-388 sumoylation. SUMO-deficient mutant PR-B (K388R) thus provides a model receptor for the study of PR function in the context of high kinase activities. T47D cells stably expressing K388R PR-B exhibited increased ligand-independent proliferation and growth in soft agar relative to cells expressing wt PR-B or phospho-mutant (sumoylated) S294A PR-B. Expression of selected PR target genes (HB-EGF, IRS-1, and STC1) was significantly elevated in cells containing desumoylated (K388R) PR-B. Basal PR transcriptional activity occurred independently of progestins, was increased by activated CDK2, and attenuated by RU486. Notably, ChIP assays demonstrated that K388R PR-B and SRC1 were constitutively recruited to the STC1 promoter in the absence of progestin; PR Lys-388 sumoylation was required for HDAC3 recruitment. Knock-down of STC1 inhibited proliferation of cells expressing K388R PR-B. These data suggest a mechanism whereby phosphorylated, and thus desumoylated, PRs mediate increased expression of growth promoting genes. Our data explain why breast cancer models often remain insensitive to progestins, but are growth-inhibited by antiprogestins, and underscore the need to target PR-B and associated kinase activities as part of breast cancer therapy.
Targeted transgenesis reveals discrete attenuator functions of GRK and PKA in airway β
2
-adrenergic receptor physiologic signaling
Authors: Wang Wayne C. H. , Mihlbachler Kathryn A. , Brunnett Alicyn C. , Liggett Stephen B.
Published: August 2009

Phosphorylation by protein kinase A (PKA) and G protein-coupled receptor kinases (GRKs) desensitize β
2
-adrenergic receptor (β
2
AR) signaling, and these are thought to be mechanisms involved with cell and organ homeostasis and tolerance to agonists. However, there is little direct evidence that these events are relevant to β
2
AR physiological function, such as airway smooth muscle (ASM) relaxation leading to bronchodilation. To maintain cell- and receptor-specificity without altering the natural complement of kinases/arrestins, transgenic mice were generated expressing the human WT and mutated β
2
ARs lacking PKA and/or GRK phosphorylation sites on ASM at ≈4-fold over background. Functional gains in response to β-agonist from the selective loss of these mechanisms were determined in mouse airways. Relaxation kinetics were altered in all mutant airways compared with β
2
WT. At low receptor occupancy, β
2
PKA(-) had enhanced agonist-promoted relaxation, while β
2
GRK(-) airways were unaffected. In contrast, at saturating agonist concentrations, the greatest relaxation enhancement was with β
2
GRK(-), with no evidence for additivity when PKA sites were also removed. For the full range of responses, the β
2
PKA(-)/GRK(-) airways had the greatest relaxation efficiency, indicating a graded effect of GRKs as agonist concentration increased. ASM cAMP levels paralleled relaxation phenotypes. No interaction between PKA phosphorylation of β
2
AR and GRK-promoted events was identified by β-arrestin-2 recruitment. Thus, these two mechanisms indeed impact a relevant β
2
AR physiologic function, acting as attenuators of the acute response, and represent specific interfaces where adjunct therapy or biased ligands may improve β-agonist treatment of obstructive lung disease.
Physical and biogeochemical modulation of ocean acidification in the central North Pacific
Authors: Dore John E. , Lukas Roger , Sadler Daniel W. , Church Matthew J. , Karl David M.
Published: August 2009

Atmospheric carbon dioxide (CO
2
) is increasing at an accelerating rate, primarily due to fossil fuel combustion and land use change. A substantial fraction of anthropogenic CO
2
emissions is absorbed by the oceans, resulting in a reduction of seawater pH. Continued acidification may over time have profound effects on marine biota and biogeochemical cycles. Although the physical and chemical basis for ocean acidification is well understood, there exist few field data of sufficient duration, resolution, and accuracy to document the acidification rate and to elucidate the factors governing its variability. Here we report the results of nearly 20 years of time-series measurements of seawater pH and associated parameters at Station ALOHA in the central North Pacific Ocean near Hawaii. We document a significant long-term decreasing trend of −0.0019 ± 0.0002 y
−1
in surface pH, which is indistinguishable from the rate of acidification expected from equilibration with the atmosphere. Superimposed upon this trend is a strong seasonal pH cycle driven by temperature, mixing, and net photosynthetic CO
2
assimilation. We also observe substantial interannual variability in surface pH, influenced by climate-induced fluctuations in upper ocean stability. Below the mixed layer, we find that the change in acidification is enhanced within distinct subsurface strata. These zones are influenced by remote water mass formation and intrusion, biological carbon remineralization, or both. We suggest that physical and biogeochemical processes alter the acidification rate with depth and time and must therefore be given due consideration when designing and interpreting ocean pH monitoring efforts and predictive models.
In vivo internal tumor illumination by telomerase-dependent adenoviral GFP for precise surgical navigation
Authors: Kishimoto Hiroyuki , Zhao Ming , Hayashi Katsuhiro , Urata Yasuo , Tanaka Noriaki , Fujiwara Toshiyoshi , Penman Sheldon , Hoffman Robert M.
Published: August 2009

Cancer surgery requires the complete and precise identification of malignant tissue margins including the smallest disseminated lesions. Internal green fluorescent protein (GFP) fluorescence can intensely illuminate even single cells but requires
GFP
sequence transcription within the cell. Introducing and selectively activating the
GFP
gene in malignant tissue in vivo is made possible by the development of OBP-401, a telomerase-dependent, replication-competent adenovirus expressing GFP. This potentially powerful adjunct to surgical navigation was demonstrated in 2 nude mouse models that represent difficult surgical challenges—the resection of widely disseminated cancer. HCT-116, a model of intraperitoneal disseminated human colon cancer, was labeled by virus injection into the peritoneal cavity. A549, a model of pleural dissemination of human lung cancer, was labeled by virus administered into the pleural cavity. Only the malignant tissue fluoresced brightly in both models. In the intraperitoneal model of disseminated cancer, fluorescence-guided surgery enabled resection of all tumor nodules labeled with GFP by OBP-401. The data in this report suggest that adenoviral-GFP labeling tumors in patients can enable fluorescence-guided surgical navigation.
Measuring prions by bioluminescence imaging
Authors: Tamgüney Gültekin , Francis Kevin P. , Giles Kurt , Lemus Azucena , DeArmond Stephen J. , Prusiner Stanley B.
Published: August 2009

Prions are infectious proteins that cause fatal neurodegenerative diseases. Because astrocytic gliosis marked by the deposition of fibrils composed of GFAP is a prominent feature of prion disease, we asked whether GFAP might be used as a surrogate marker for prions. To interrogate this posit, we inoculated prions into transgenic (Tg) mice expressing luciferase (luc) under the GFAP gene (
Gfap
) promoter, denoted Tg(
Gfap
-luc) mice. Weekly noninvasive, bioluminescence imaging (BLI) detected an increase in light emitted from the brains of Tg(
Gfap
-luc) mice at ≈55 d after inoculation and ≈62 d before neurologic deficits appeared. To determine whether BLI could be used as a proxy bioassay for prion infectivity, we performed endpoint titrations of prions in Tg(
Gfap
-luc) mice. BLI bioassays were as or more sensitive than those determined by the onset of neurological dysfunction, and were completed in approximately half the time. Our studies argue that BLI is likely to be a suitable surrogate for measuring prion infectivity, and might be useful in the study of Tg mouse models for other neurodegenerative illnesses.
Stimulus ensemble and cortical layer determine V1 spatial receptive fields
Authors: Yeh Chun-I , Xing Dajun , Williams Patrick E. , Shapley Robert M.
Published: August 2009

The concept of receptive field is a linear, feed-forward view of visual signal processing. Frequently used models of V1 neurons, like the dynamic linear filter static nonlinearity Poisson spike encoder model, predict that receptive fields measured with different stimulus ensembles should be similar. Here, we tested this concept by comparing spatiotemporal maps of V1 neurons derived from two very different, but commonly used, stimulus ensembles: sparse noise and Hartley subspace stimuli. We found maps from the two methods agreed for neurons in input layer 4C but were very different for neurons in superficial layers of V1. Many layer 2/3 cells have receptive fields with multiple elongated subregions when mapped with Hartley stimuli, but their spatial maps collapse to only a single, less-elongated subregion when mapped with sparse noise. Moreover, for upper layer V1 neurons, the preferred orientation for Hartley maps is much closer to the preferred orientation measured with drifting gratings than is the orientation preference of sparse-noise maps. These results challenge the concept of a stimulus-invariant receptive field and imply that intracortical interactions shape fundamental properties of layer 2/3 neurons.
Bacterial growth and motility in sub-micron constrictions
Authors: Männik Jaan , Driessen Rosalie , Galajda Peter , Keymer Juan E. , Dekker Cees
Published: August 2009

In many naturally occurring habitats, bacteria live in micrometer-size confined spaces. Although bacterial growth and motility in such constrictions is of great interest to fields as varied as soil microbiology, water purification, and biomedical research, quantitative studies of the effects of confinement on bacteria have been limited. Here, we establish how Gram-negative
Escherichia coli
and Gram-positive
Bacillus subtilis
bacteria can grow, move, and penetrate very narrow constrictions with a size comparable to or even smaller than their diameter. We show that peritrichously flagellated
E. coli
and
B. subtilis
are still motile in microfabricated channels where the width of the channel exceeds their diameters only marginally (∼30%). For smaller widths, the motility vanishes but bacteria can still pass through these channels by growth and division. We observe
E. coli
, but not
B. subtilis
, to penetrate channels with a width that is smaller than their diameter by a factor of approximately 2. Within these channels, bacteria are considerably squeezed but they still grow and divide. After exiting the channels,
E. coli
bacteria obtain a variety of anomalous cell shapes. Our results reveal that sub-micron size pores and cavities are unexpectedly prolific bacterial habitats where bacteria exhibit morphological adaptations.
Value of high‐risk HPV‐DNA testing in the triage of ASCUS
Authors: SILVERLOO IRÉNE , ANDRAE BENGT , WILANDER ERIK
Published: August 2009

Objective. Atypical squamous cells of undetermined significance (ASCUS) cells, occurring in organized cytological screening, may be either high‐risk human papillomavirus (HPV) positive or negative. To refine the assessment of women with ASCUS, a high‐risk HPV‐DNA test is recommended as triage in Sweden. Methods. A total of 197 consecutive women (mean age 39 years, range 21–60) with a diagnosis of ASCUS from the primary screening were selected for triage. Their cervical smears were collected and evaluated by using conventional cytological examination in combination with a high‐risk HPV‐DNA test (hybrid capture 2). The women were categorized into four groups: Group A, Cytology + /HPV +; Group B, Cytology–/HPV +; Group C, Cytology + /HPV–; and Group D, Cytology–/ HPV–. Women within Groups A–C were admitted for colposcopy and cervical biopsy. The women in Group D were considered as a low‐risk group for tumor development, and were re‐examined after three years in the next round of the organized screening. Results. In women in Group A (n = 58) the prevalence of histological verified CIN2–3 was 41%, in Group B (n = 41) 20%, and in Group C (n = 9) 0%. In Group D (n = 89), repeated primary screening three years later revealed CIN2–3 in two biopsies from 74 women studied (<3%). The prevalence of a high‐risk HPV infection decreased with age in women with ASCUS. It was 74% in women <30 years and 19% in women ≥50 years. Conclusions. Adding a high‐risk HPV test in secondary screening increased the identification of women with CIN2–3 lesions by 33% in comparison with repeat cytology (p = 0.01). The clinical significance of the ASCUS diagnosis varied with age of the women.
Constructing inclusive education in a neo‐liberal context: Promoting inclusion of Arab‐Australian students in an Australian context
Authors: Kamp Annelies , Mansouri Fethi
Published: August 2009

School systems are a major social change agent capable of challenging social inequalities and economic disadvantages. Yet, while schools in Australia are being confronted with increasingly culturally diverse populations as well as an increasing focus on student retention, this transformative role is increasingly being played out in a broader educational context that has been found to replicate rather than challenge patterns of social inequality. Successive governments in Australia have responded to this context with a raft of policy initiatives. This paper, based on three‐year longitudinal research undertaken in the city of Melbourne, outlines this policy context and introduces the theoretical approach that underpins its innovative approach to managing cultural diversity in educational institutions. It argues for, and presents, a multidimensional model for managing cultural diversity in schools, one that provides the tools for transformative practices to be undertaken to effect positive change in school environments for the benefit of all students.
Early use of phonetic information in spoken word recognition: Lexical stress drives eye movements immediately
Authors: Reinisch Eva , Jesse Alexandra , McQueen James M.
Published: August 2009

For optimal word recognition listeners should use all relevant acoustic information as soon as it comes available. Using printed-word eye tracking we investigated when during word processing Dutch listeners use suprasegmental lexical stress information to recognize words. Fixations on targets such as “OCtopus” (capitals indicate stress) were more frequent than fixations on segmentally overlapping but differently stressed competitors (“okTOber”) before segmental information could disambiguate the words. Furthermore, prior to segmental disambiguation, initially stressed words were stronger lexical competitors than noninitially stressed words. Listeners recognize words by immediately using all relevant information in the speech signal.
Social-comparative feedback affects motor skill learning
Authors: Lewthwaite Rebecca , Wulf Gabriele
Published: August 2009

This study examined motivational effects of feedback on motor learning. Specifically, we investigated the influence of social-comparative feedback on the learning of a balance task (stabilometer). In addition to veridical feedback (error scores reflecting deviation from the target horizontal platform position) about their own performance after each trial, two groups received false normative information about the “average” score of others on that trial. Average performance scores indicated that the participant's performance was either above (better group) or below (worse group) the average, respectively. A control group received veridical feedback about trial performance without normative feedback. Learning as a function of social-comparative feedback was determined in a retention test without feedback, performed on a third day following two days of practice. Normative feedback affected the learning of the balance task: The better group demonstrated more effective balance performance than both the worse and control groups on the retention test. Furthermore, high-frequency/low-amplitude balance adjustments, indicative of more automatic control of movement, were greater in the better than in the worse group. The control group exhibited more limited learning and less automaticity than both the better and the worse groups. The findings indicate that positive normative feedback had a facilitatory effect on motor learning.
Expertise makes the world slow down: Judgements of duration are influenced by domain knowledge
Authors: Rhodes Matthew G. , McCabe David P.
Published: August 2009

Experts often appear to perceive time differently from novices. The current study thus examined perceptions of time as a function of domain expertise. Specifically, individuals with high or low levels of knowledge of American football made judgements of duration for briefly presented words that were unrelated to football (e.g., rooster), football specific (e.g., touchdown), or ambiguous (e.g., huddle). Results showed that high-knowledge individuals judged football-specific words as having been presented for a longer duration than unrelated or ambiguous words. In contrast, low-knowledge participants exhibited no systematic differences in judgements of duration based on the type of word presented. These findings are discussed within a fluency attribution framework, which suggests that experts’ fluent perception of domain-relevant stimuli leads to the subjective impression that time slows down in one's domain of expertise.
Because there was a cause for concern: An investigation into a word-specific prediction account of the implicit-causality effect
Authors: Featherstone Cara R. , Sturt Patrick
Published: August 2009

In Koornneef and Van Berkum's (2006) eye-tracking study of implicit causality (Caramazza, Grober, Garvey, & Yates, 1977), midsentence delays were observed in the processing of sentences such as “ David blamed Linda because she(bias-congruent)/ he(bias-incongruent) … ” when the pronoun following because was incongruent with the bias of the implicit-causality verb. The authors suggested that these immediate delays could be attributed to participants predicting a bias-congruent pronoun after because. According to this explanation, any other word placed after because should cause processing delays. The present investigation aimed to test this explanation by using sentences of the form “ David blamed Linda because she(bias-congruent)/ he(bias-incongruent)/ there(bias-neutral) … ”. Since significant immediate delays were observed in sentences containing a bias-incongruent pronoun (relative to a bias-congruent pronoun) but not in sentences containing there, the results of this study support an immediate integration effect but pose a problem to the word-specific prediction account of the implicit causality effect.
Steric and not structure-specific factors dictate the endocytic mechanism of glycosylphosphatidylinositol-anchored proteins
Authors: Bhagatji Pinkesh , Leventis Rania , Comeau Jonathan , Refaei Mohammad , Silvius John R.
Published: August 2009

Diverse glycosylphosphatidylinositol (GPI)-anchored proteins enter mammalian cells via the clathrin- and dynamin-independent, Arf1-regulated GPI-enriched early endosomal compartment/clathrin-independent carrier endocytic pathway. To characterize the determinants of GPI protein targeting to this pathway, we have used fluorescence microscopic analyses to compare the internalization of artificial lipid-anchored proteins, endogenous membrane proteins, and membrane lipid markers in Chinese hamster ovary cells. Soluble proteins, anchored to cell-inserted saturated or unsaturated phosphatidylethanolamine (PE)-polyethyleneglycols (PEGs), closely resemble the GPI-anchored folate receptor but differ markedly from the transferrin receptor, membrane lipid markers, and even protein-free PE-PEGs, both in their distribution in peripheral endocytic vesicles and in the manner in which their endocytic uptake responds to manipulations of cellular Arf1 or dynamin activity. These findings suggest that the distinctive endocytic targeting of GPI proteins requires neither biospecific recognition of their GPI anchors nor affinity for ordered-lipid microdomains but is determined by a more fundamental property, the steric bulk of the lipid-anchored protein.
Myosin-driven peroxisome partitioning inS. cerevisiae
Authors: Fagarasanu Andrei , Mast Fred D. , Knoblach Barbara , Jin Yui , Brunner Matthew J. , Logan Michael R. , Glover J.N. Mark , Eitzen Gary A. , Aitchison John D. , Weisman Lois S. , Rachubinski Richard A.
Published: August 2009

In Saccharomyces cerevisiae, the class V myosin motor Myo2p propels the movement of most organelles. We recently identified Inp2p as the peroxisome-specific receptor for Myo2p. In this study, we delineate the region of Myo2p devoted to binding peroxisomes. Using mutants of Myo2p specifically impaired in peroxisome binding, we dissect cell cycle–dependent and peroxisome partitioning–dependent mechanisms of Inp2p regulation. We find that although total Inp2p levels oscillate with the cell cycle, Inp2p levels on individual peroxisomes are controlled by peroxisome inheritance, as Inp2p aberrantly accumulates and decorates all peroxisomes in mother cells when peroxisome partitioning is abolished. We also find that Inp2p is a phosphoprotein whose level of phosphorylation is coupled to the cell cycle irrespective of peroxisome positioning in the cell. Our findings demonstrate that both organelle positioning and cell cycle progression control the levels of organelle-specific receptors for molecular motors to ultimately achieve an equidistribution of compartments between mother and daughter cells.
Oncogene homologue Sch9 promotes age-dependent mutations by a superoxide and Rev1/Polζ-dependent mechanism
Authors: Madia Federica , Wei Min , Yuan Valerie , Hu Jia , Gattazzo Cristina , Pham Phuong , Goodman Myron F. , Longo Valter D.
Published: August 2009

Oncogenes contribute to tumorigenesis by promoting growth and inhibiting apoptosis. Here we examine the function of Sch9, the Saccharomyces cerevisiae homologue of the mammalian Akt and S6 kinase, in DNA damage and genomic instability during aging in nondividing cells. Attenuation of age-dependent increases in base substitutions, small DNA insertions/deletions, and gross chromosomal rearrangements (GCRs) in sch9Δ mutants is associated with increased mitochondrial superoxide dismutase (MnSOD) expression, decreased DNA oxidation, reduced REV1 expression and translesion synthesis, and elevated resistance to oxidative stress-induced mutagenesis. Deletion of REV1, the lack of components of the error-prone Polζ, or the overexpression of SOD1 or SOD2 is sufficient to reduce age-dependent point mutations in SCH9 overexpressors, but REV1 deficiency causes a major increase in GCRs. These results suggest that the proto-oncogene homologue Sch9 promotes the accumulation of superoxide-dependent DNA damage in nondividing cells, which induces error-prone DNA repair that generates point mutations to avoid GCRs and cell death during the first round of replication.
Endocytosis of lipid-anchored proteins: excluding GEECs from the crowd
Authors: Nichols Ben
Published: August 2009

Endocytosis of glycosylphosphatidylinositol (GPI)-linked proteins via a specific pathway into GPI-enriched early endosomal compartments (GEECs) has been proposed. How sorting into this pathway may take place is unclear. In this issue, Bhagatji et al. (2009. J. Cell Biol. doi:10.1083/jcb.200903102) provide an original mechanism for the sorting of lipid-anchored proteins that involves exclusion of bulky extracellular domains from clathrin-coated pits.
Dissection of PIM serine/threonine kinases in FLT3-ITD–induced leukemogenesis reveals PIM1 as regulator of CXCL12–CXCR4-mediated homing and migration
Authors: Grundler Rebekka , Brault Laurent , Gasser Christelle , Bullock Alex N. , Dechow Tobias , Woetzel Sabine , Pogacic Vanda , Villa Antonello , Ehret Sabine , Berridge Georgina , Spoo Anke , Dierks Christine , Biondi Andrea , Knapp Stefan , Duyster Justus , Schwaller Juerg
Published: August 2009

FLT3-ITD–mediated leukemogenesis is associated with increased expression of oncogenic PIM serine/threonine kinases. To dissect their role in FLT3-ITD–mediated transformation, we performed bone marrow reconstitution assays. Unexpectedly, FLT3-ITD cells deficient for PIM1 failed to reconstitute lethally irradiated recipients, whereas lack of PIM2 induction did not interfere with FLT3-ITD–induced disease. PIM1-deficient bone marrow showed defects in homing and migration and displayed decreased surface CXCR4 expression and impaired CXCL12–CXCR4 signaling. Through small interfering RNA–mediated knockdown, chemical inhibition, expression of a dominant-negative mutant, and/or reexpression in knockout cells, we found PIM1 activity to be essential for proper CXCR4 surface expression and migration of cells toward a CXCL12 gradient. Purified PIM1 led to the phosphorylation of serine 339 in the CXCR4 intracellular domain in vitro, a site known to be essential for normal receptor recycling. In primary leukemic blasts, high levels of surface CXCR4 were associated with increased PIM1 expression, and this could be significantly reduced by a small molecule PIM inhibitor in some patients. Our data suggest that PIM1 activity is important for homing and migration of hematopoietic cells through modification of CXCR4. Because CXCR4 also regulates homing and maintenance of cancer stem cells, PIM1 inhibitors may exert their antitumor effects in part by interfering with interactions with the microenvironment.
Augmented TLR9-induced Btk activation in PIR-B–deficient B-1 cells provokes excessive autoantibody production and autoimmunity
Authors: Kubo Tomohiro , Uchida Yuki , Watanabe Yuko , Abe Masahiro , Nakamura Akira , Ono Masao , Akira Shizuo , Takai Toshiyuki
Published: August 2009

Pathogens are sensed by Toll-like receptors (TLRs) expressed in leukocytes in the innate immune system. However, excess stimulation of TLR pathways is supposed to be connected with provocation of autoimmunity. We show that paired immunoglobulin (Ig)-like receptor B (PIR-B), an immunoreceptor tyrosine-based inhibitory motif–harboring receptor for major histocompatibility class I molecules, on relatively primitive B cells, B-1 cells, suppresses TLR9 signaling via Bruton's tyrosine kinase (Btk) dephosphorylation, which leads to attenuated activation of nuclear factor κB p65RelA but not p38 or Erk, and blocks the production of natural IgM antibodies, including anti-IgG Fc autoantibodies, particularly rheumatoid factor. The autoantibody production in PIR-B–deficient (Pirb−/−) mice was further augmented in combination with the Faslpr mutation, which might be linked to the development of autoimmune glomerulonephritis. These results show the critical link between TLR9-mediated sensing and a simultaneously evoked, PIR-B–mediated inhibitory circuit with a Btk intersection in B-1 cells, and suggest a novel way toward preventing pathogenic natural autoantibody production.
The surface-anchored NanA protein promotes pneumococcal brain endothelial cell invasion
Authors: Uchiyama Satoshi , Carlin Aaron F. , Khosravi Arya , Weiman Shannon , Banerjee Anirban , Quach Darin , Hightower George , Mitchell Tim J. , Doran Kelly S. , Nizet Victor
Published: August 2009

In humans, Streptococcus pneumoniae (SPN) is the leading cause of bacterial meningitis, a disease with high attributable mortality and frequent permanent neurological sequelae. The molecular mechanisms underlying the central nervous system tropism of SPN are incompletely understood, but include a primary interaction of the pathogen with the blood–brain barrier (BBB) endothelium. All SPN strains possess a gene encoding the surface-anchored sialidase (neuraminidase) NanA, which cleaves sialic acid on host cells and proteins. Here, we use an isogenic SPN NanA-deficient mutant and heterologous expression of the protein to show that NanA is both necessary and sufficient to promote SPN adherence to and invasion of human brain microvascular endothelial cells (hBMECs). NanA-mediated hBMEC invasion depends only partially on sialidase activity, whereas the N-terminal lectinlike domain of the protein plays a critical role. NanA promotes SPN–BBB interaction in a murine infection model, identifying the protein as proximal mediator of CNS entry by the pathogen.
Distinct subdomains of the KCNQ1 S6 segment determine channel modulation by different KCNE subunits
Authors: Vanoye Carlos G. , Welch Richard C. , Daniels Melissa A. , Manderfield Lauren J. , Tapper Andrew R. , Sanders Charles R. , George Alfred L.
Published: August 2009

Modulation of voltage-gated potassium (KV) channels by the KCNE family of single transmembrane proteins has physiological and pathophysiological importance. All five KCNE proteins (KCNE1–KCNE5) have been demonstrated to modulate heterologously expressed KCNQ1 (KV7.1) with diverse effects, making this channel a valuable experimental platform for elucidating structure–function relationships and mechanistic differences among members of this intriguing group of accessory subunits. Here, we specifically investigated the determinants of KCNQ1 inhibition by KCNE4, the least well-studied KCNE protein. In CHO-K1 cells, KCNQ1, but not KCNQ4, is strongly inhibited by coexpression with KCNE4. By studying KCNQ1-KCNQ4 chimeras, we identified two adjacent residues (K326 and T327) within the extracellular end of the KCNQ1 S6 segment that determine inhibition of KCNQ1 by KCNE4. This dipeptide motif is distinct from neighboring S6 sequences that enable modulation by KCNE1 and KCNE3. Conversely, S6 mutations (S338C and F340C) that alter KCNE1 and KCNE3 effects on KCNQ1 do not abrogate KCNE4 inhibition. Further, KCNQ1-KCNQ4 chimeras that exhibited resistance to the inhibitory effects of KCNE4 still interact biochemically with this protein, implying that accessory subunit binding alone is not sufficient for channel modulation. These observations indicate that the diverse functional effects observed for KCNE proteins depend, in part, on structures intrinsic to the pore-forming subunit, and that distinct S6 subdomains determine KCNQ1 responses to KCNE1, KCNE3, and KCNE4.