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51.
This paper first shows that survey‐based expectations (SBE) outperform standard time series models in US quarterly inflation out‐of‐sample prediction and that the term structure of survey‐based inflation forecasts has predictive power over the path of future inflation changes. It then proposes some empirical explanations for the forecasting success of survey‐based inflation expectations. We show that SBE pool a large amount of heterogeneous information on inflation expectations and react more flexibly and accurately to macro conditions both contemporaneously and dynamically. We illustrate the flexibility of SBE forecasts in the context of the 2008 financial crisis. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
52.
Maize HapMap2 identifies extant variation from a genome in flux 总被引:3,自引:0,他引:3
Chia JM Song C Bradbury PJ Costich D de Leon N Doebley J Elshire RJ Gaut B Geller L Glaubitz JC Gore M Guill KE Holland J Hufford MB Lai J Li M Liu X Lu Y McCombie R Nelson R Poland J Prasanna BM Pyhäjärvi T Rong T Sekhon RS Sun Q Tenaillon MI Tian F Wang J Xu X Zhang Z Kaeppler SM Ross-Ibarra J McMullen MD Buckler ES Zhang G Xu Y Ware D 《Nature genetics》2012,44(7):803-807
Whereas breeders have exploited diversity in maize for yield improvements, there has been limited progress in using beneficial alleles in undomesticated varieties. Characterizing standing variation in this complex genome has been challenging, with only a small fraction of it described to date. Using a population genetics scoring model, we identified 55 million SNPs in 103 lines across pre-domestication and domesticated Zea mays varieties, including a representative from the sister genus Tripsacum. We find that structural variations are pervasive in the Z. mays genome and are enriched at loci associated with important traits. By investigating the drivers of genome size variation, we find that the larger Tripsacum genome can be explained by transposable element abundance rather than an allopolyploid origin. In contrast, intraspecies genome size variation seems to be controlled by chromosomal knob content. There is tremendous overlap in key gene content in maize and Tripsacum, suggesting that adaptations from Tripsacum (for example, perennialism and frost and drought tolerance) can likely be integrated into maize. 相似文献
53.
54.
Postel-Vinay S Véron AS Tirode F Pierron G Reynaud S Kovar H Oberlin O Lapouble E Ballet S Lucchesi C Kontny U González-Neira A Picci P Alonso J Patino-Garcia A de Paillerets BB Laud K Dina C Froguel P Clavel-Chapelon F Doz F Michon J Chanock SJ Thomas G Cox DG Delattre O 《Nature genetics》2012,44(3):323-327
Ewing sarcoma, a pediatric tumor characterized by EWSR1-ETS fusions, is predominantly observed in populations of European ancestry. We performed a genome-wide association study (GWAS) of 401 French individuals with Ewing sarcoma, 684 unaffected French individuals and 3,668 unaffected individuals of European descent and living in the United States. We identified candidate risk loci at 1p36.22, 10q21 and 15q15. We replicated these loci in two independent sets of cases and controls. Joint analysis identified associations with rs9430161 (P = 1.4 × 10(-20); odds ratio (OR) = 2.2) located 25 kb upstream of TARDBP, rs224278 (P = 4.0 × 10(-17); OR = 1.7) located 5 kb upstream of EGR2 and, to a lesser extent, rs4924410 at 15q15 (P = 6.6 × 10(-9); OR = 1.5). The major risk haplotypes were less prevalent in Africans, suggesting that these loci could contribute to geographical differences in Ewing sarcoma incidence. TARDBP shares structural similarities with EWSR1 and FUS, which encode RNA binding proteins, and EGR2 is a target gene of EWSR1-ETS. Variants at these loci were associated with expression levels of TARDBP, ADO (encoding cysteamine dioxygenase) and EGR2. 相似文献
55.
Extremely low-coverage sequencing and imputation increases power for genome-wide association studies 总被引:1,自引:0,他引:1
Pasaniuc B Rohland N McLaren PJ Garimella K Zaitlen N Li H Gupta N Neale BM Daly MJ Sklar P Sullivan PF Bergen S Moran JL Hultman CM Lichtenstein P Magnusson P Purcell SM Haas DW Liang L Sunyaev S Patterson N de Bakker PI Reich D Price AL 《Nature genetics》2012,44(6):631-635
Genome-wide association studies (GWAS) have proven to be a powerful method to identify common genetic variants contributing to susceptibility to common diseases. Here, we show that extremely low-coverage sequencing (0.1-0.5×) captures almost as much of the common (>5%) and low-frequency (1-5%) variation across the genome as SNP arrays. As an empirical demonstration, we show that genome-wide SNP genotypes can be inferred at a mean r(2) of 0.71 using off-target data (0.24× average coverage) in a whole-exome study of 909 samples. Using both simulated and real exome-sequencing data sets, we show that association statistics obtained using extremely low-coverage sequencing data attain similar P values at known associated variants as data from genotyping arrays, without an excess of false positives. Within the context of reductions in sample preparation and sequencing costs, funds invested in extremely low-coverage sequencing can yield several times the effective sample size of GWAS based on SNP array data and a commensurate increase in statistical power. 相似文献
56.
Roscioli T Kamsteeg EJ Buysse K Maystadt I van Reeuwijk J van den Elzen C van Beusekom E Riemersma M Pfundt R Vissers LE Schraders M Altunoglu U Buckley MF Brunner HG Grisart B Zhou H Veltman JA Gilissen C Mancini GM Delrée P Willemsen MA Ramadža DP Chitayat D Bennett C Sheridan E Peeters EA Tan-Sindhunata GM de Die-Smulders CE Devriendt K Kayserili H El-Hashash OA Stemple DL Lefeber DJ Lin YY van Bokhoven H 《Nature genetics》2012,44(5):581-585
Walker-Warburg syndrome (WWS) is an autosomal recessive multisystem disorder characterized by complex eye and brain abnormalities with congenital muscular dystrophy (CMD) and aberrant a-dystroglycan glycosylation. Here we report mutations in the ISPD gene (encoding isoprenoid synthase domain containing) as the second most common cause of WWS. Bacterial IspD is a nucleotidyl transferase belonging to a large glycosyltransferase family, but the role of the orthologous protein in chordates is obscure to date, as this phylum does not have the corresponding non-mevalonate isoprenoid biosynthesis pathway. Knockdown of ispd in zebrafish recapitulates the human WWS phenotype with hydrocephalus, reduced eye size, muscle degeneration and hypoglycosylated a-dystroglycan. These results implicate ISPD in a-dystroglycan glycosylation in maintaining sarcolemma integrity in vertebrates. 相似文献
57.
Bis JC DeCarli C Smith AV van der Lijn F Crivello F Fornage M Debette S Shulman JM Schmidt H Srikanth V Schuur M Yu L Choi SH Sigurdsson S Verhaaren BF DeStefano AL Lambert JC Jack CR Struchalin M Stankovich J Ibrahim-Verbaas CA Fleischman D Zijdenbos A den Heijer T Mazoyer B Coker LH Enzinger C Danoy P Amin N Arfanakis K van Buchem MA de Bruijn RF Beiser A Dufouil C Huang J Cavalieri M Thomson R Niessen WJ Chibnik LB Gislason GK Hofman A Pikula A Amouyel P Freeman KB Phan TG Oostra BA Stein JL 《Nature genetics》2012,44(5):545-551
Aging is associated with reductions in hippocampal volume that are accelerated by Alzheimer's disease and vascular risk factors. Our genome-wide association study (GWAS) of dementia-free persons (n = 9,232) identified 46 SNPs at four loci with P values of <4.0 × 10(-7). In two additional samples (n = 2,318), associations were replicated at 12q14 within MSRB3-WIF1 (discovery and replication; rs17178006; P = 5.3 × 10(-11)) and at 12q24 near HRK-FBXW8 (rs7294919; P = 2.9 × 10(-11)). Remaining associations included one SNP at 2q24 within DPP4 (rs6741949; P = 2.9 × 10(-7)) and nine SNPs at 9p33 within ASTN2 (rs7852872; P = 1.0 × 10(-7)); along with the chromosome 12 associations, these loci were also associated with hippocampal volume (P < 0.05) in a third younger, more heterogeneous sample (n = 7,794). The SNP in ASTN2 also showed suggestive association with decline in cognition in a largely independent sample (n = 1,563). These associations implicate genes related to apoptosis (HRK), development (WIF1), oxidative stress (MSR3B), ubiquitination (FBXW8) and neuronal migration (ASTN2), as well as enzymes targeted by new diabetes medications (DPP4), indicating new genetic influences on hippocampal size and possibly the risk of cognitive decline and dementia. 相似文献
58.
Amiot L Ferrone S Grosse-Wilde H Seliger B 《Cellular and molecular life sciences : CMLS》2011,68(3):417-431
Although the expression of the non-classical HLA class I molecule HLA-G was first reported to be restricted to the fetal–maternal
interface on the extravillous cytotrophoblasts, the distribution of HLA-G in normal tissues appears broader than originally
described. HLA-G expression was found in embryonic tissues, in adult immune privileged organs, and in cells of the hematopoietic
lineage. More interestingly, under pathophysiological conditions HLA-G antigens may be expressed on various types of malignant
cells suggesting that HLA-G antigen expression is one strategy used by tumor cells to escape immune surveillance. In this
article, we will focus on HLA-G expression in cancers of distinct histology and its association with the clinical course of
diseases, on the underlying molecular mechanisms of impaired HLA-G expression, on the immune tolerant function of HLA-G in
tumors, and on the use of membrane-bound and soluble HLA-G as a diagnostic or prognostic biomarker to identify tumors and
to monitor disease stage, as well as on the use of HLA-G as a novel therapeutic target in cancer. 相似文献
59.
Biegel E Schmidt S González JM Müller V 《Cellular and molecular life sciences : CMLS》2011,68(4):613-634
Microbes have a fascinating repertoire of bioenergetic enzymes and a huge variety of electron transport chains to cope with
very different environmental conditions, such as different oxygen concentrations, different electron acceptors, pH and salinity.
However, all these electron transport chains cover the redox span from NADH + H+ as the most negative donor to oxygen/H2O as the most positive acceptor or increments thereof. The redox range more negative than −320 mV has been largely ignored.
Here, we have summarized the recent data that unraveled a novel ion-motive electron transport chain, the Rnf complex, that
energetically couples the cellular ferredoxin to the pyridine nucleotide pool. The energetics of the complex and its biochemistry,
as well as its evolution and cellular function in different microbes, is discussed. 相似文献
60.
Rai A Nöthe H Tzvetkov N Korenbaum E Manstein DJ 《Cellular and molecular life sciences : CMLS》2011,68(16):2751-2767
Dictyostelium discoideum cells produce five dynamin family proteins. Here, we show that dynamin B is the only member of this group of proteins that
is initially produced as a preprotein and requires processing by mitochondrial proteases for formation of the mature protein.
Our results show that dynamin B-depletion affects many aspects of cell motility, cell-cell and cell-surface adhesion, resistance
to osmotic shock, and fatty acid metabolism. The mature form of dynamin B mediates a wide range and unique combination of
functions. Dynamin B affects events at the plasma membrane, peroxisomes, the contractile vacuole system, components of the
actin-based cytoskeleton, and cell adhesion sites. The modulating effect of dynamin B on the activity of the contractile vacuole
system is unique for the Dictyostelium system. Other functions displayed by dynamin B are commonly associated with either classical dynamins or dynamin-related
proteins. 相似文献