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601.
The Middle Miocene Marnoso-arenacea Formation at Deruta in the northern Apennines of Italy rests unconformably on an orogenic
wedge adjacent to the Adriatic foredeep. Based on a detailed facies analysis, the succession reveals two genetically related
depositional systems: a distal delta-fed sand-rich system and a more proximal fan-delta slope system. Petrographic data confirm
the genetic relationship between the two depositional systems, with the fan-delta slope feeding the basinward sand-rich system.
The Deruta depositional setting shows a multi-step sedimentary evolution controlled by tectonically induced relative sea-level
changes. The first stage, corresponding to a sea-level rise, promoted deposition in a wedge-top basin of pebbly sand and sand
lobes (delta-fed). The second stage, characterized by intense tectonic activity (uplift) and sea-level fall, promoted accumulation
of a prograding fan-delta slope replacing the sand-rich lobes. This phase was dominated by mass failures and methanogenic
cold seepages. During these two stages, the wedge-top basin was isolated from the adjacent foredeep. Only during the third
stage was a connection established, with the development of a deep-sea fan in the foredeep, fed by a deltaic depositional
system. 相似文献
602.
Emanuela Senatore Francesco Chiuso Laura Rinaldi Daniela Intartaglia Rossella Delle Donne Emilia Pedone Bruno Catalanotti Luciano Pirone Bianca Fiorillo Federica Moraca Giuliana Giamundo Giovanni Scala Andrea Raffeiner Omar TorresQuesada Eduard Stefan Marcel Kwiatkowski Alienke van Pijkeren Manuela Morleo Brunella Franco Corrado Garbi Ivan Conte Antonio Feliciello 《The EMBO journal》2021,40(10)
The primary cilium is a microtubule‐based sensory organelle that dynamically links signalling pathways to cell differentiation, growth, and development. Genetic defects of primary cilia are responsible for genetic disorders known as ciliopathies. Orofacial digital type I syndrome (OFDI) is an X‐linked congenital ciliopathy caused by mutations in the OFD1 gene and characterized by malformations of the face, oral cavity, digits and, in the majority of cases, polycystic kidney disease. OFD1 plays a key role in cilium biogenesis. However, the impact of signalling pathways and the role of the ubiquitin‐proteasome system (UPS) in the control of OFD1 stability remain unknown. Here, we identify a novel complex assembled at centrosomes by TBC1D31, including the E3 ubiquitin ligase praja2, protein kinase A (PKA), and OFD1. We show that TBC1D31 is essential for ciliogenesis. Mechanistically, upon G‐protein‐coupled receptor (GPCR)‐cAMP stimulation, PKA phosphorylates OFD1 at ser735, thus promoting OFD1 proteolysis through the praja2‐UPS circuitry. This pathway is essential for ciliogenesis. In addition, a non‐phosphorylatable OFD1 mutant dramatically affects cilium morphology and dynamics. Consistent with a role of the TBC1D31/praja2/OFD1 axis in ciliogenesis, alteration of this molecular network impairs ciliogenesis in vivo in Medaka fish, resulting in developmental defects. Our findings reveal a multifunctional transduction unit at the centrosome that links GPCR signalling to ubiquitylation and proteolysis of the ciliopathy protein OFD1, with important implications on cilium biology and development. Derangement of this control mechanism may underpin human genetic disorders. 相似文献
603.
Claudio Pettinari Ivan Timokhin Corrado Di Nicola Allan H. White 《Inorganica chimica acta》2011,367(1):98-107
Novel triorganotin(IV) derivatives of β-diketonate Q ligands (HQ in general, in detail HQfur = 1-phenyl-3-methyl-4-(2-furancarbonyl)-pyrazol-5-one, HQthi = 1-phenyl-3-methyl-4-(2-thienylcarbonyl)-pyrazol-5-one) of general formula (Q)SnR3·xH2O (R = Ph, x = 0; R = Bun or Me, x = 1) have been synthesized and spectroscopically and thermally characterized. Triphenyltin(IV) complexes have been isolated as anhydrous compounds while trialkyltin(IV) are always monohydrated. The structures of (Qfur)SnPh3 and (Qthi)SnMe3(OH2) are recorded. The tin atoms are five-coordinate in both. In the first, the pyrazolonate ligand behaves as an O,O′-bidentate; there are two similar but independent molecules in the structure. In the quasi-trigonal-bipyramidal environments, Sn-O(acyl) are 2.478(3), 2.364(3), Sn-O(pyrazolonate) 2.050(2), 2.079(2), Sn-C 2.123(4)-2.162(3) Å with the longer O(acyl) and a phenyl group quasi-trans (O-Sn-C 162.5(1), 160.8(1)°). In (Qthi)SnMe3(OH2), the three methyl groups are equatorial (Sn-C 2.1259(9)-2.1380(8) Å); Sn-O(Qthi,OH2) are 2.2143(5), 2.3350(6) Å, O-Sn-O 175.36(2)°. Trimethyltin(IV) derivatives decompose on heating with release of H2O and SnMe4 and formation of (Q)2SnMe2. Decomposition occurs also within two days after dissolution of (Q)SnMe3(OH2) in chloroform. 相似文献
604.
605.
Sébastien Lacroix Mario Lauria Marie-Pier Scott-Boyer Luca Marchetti Corrado Priami Laura Caberlotto 《Genes & nutrition》2015,10(6)
Worldwide population is aging, and a large part of the growing burden associated with age-related conditions can be prevented or delayed by promoting healthy lifestyle and normalizing metabolic risk factors. However, a better understanding of the pleiotropic effects of available nutritional interventions and their influence on the multiple processes affected by aging is needed to select and implement the most promising actions. New methods of analysis are required to tackle the complexity of the interplay between nutritional interventions and aging, and to make sense of a growing amount of -omics data being produced for this purpose. In this paper, we review how various systems biology-inspired methods of analysis can be applied to the study of the molecular basis of nutritional interventions promoting healthy aging, notably caloric restriction and polyphenol supplementation. We specifically focus on the role that different versions of network analysis, molecular signature identification and multi-omics data integration are playing in elucidating the complex mechanisms underlying nutrition, and provide some examples on how to extend the application of these methods using available microarray data.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-015-0508-9) contains supplementary material, which is available to authorized users. 相似文献606.
607.
Luis Navarro Garbi?e Ayensa Victoria Ferrero José María Sánchez 《Plant Ecology》2012,213(11):1813-1822
Hermaphrodite flowers usually possess floral traits to avoid the negative effects derived from inbreeding depression and/or self-interference between pollen export and reception, both acting as the main selective pressures on those floral traits. The avoidance of self-interference is widely accepted as the primary force promoting the separation between sexes within the flowers in time (dichogamy) and/or space (herkogamy) for self-incompatible species, which are already protected from the negative effects of inbreeding depression by the incompatibility system. Different degrees of incompatibility, herkogamy, and dichogamy have been reported for the genus Narcissus. However, the only mechanism for the separation of sexes reported up to date for Narcissus cyclamineus is herkogamy, while the presence of dichogamy and the type of incompatibility in this species remain uncertain. In this study, we analyze the patterns of sexual reproduction in N. cyclamineus to ascertain whether there is any selective pressure favouring sexual segregation or its maintenance and their mechanisms. N. cyclamineus is self-incompatible and dichogamy can be rejected for this species. Even though the species is self-incompatible, when cross-pollination is preceded by self-pollination the number of ovules available for legitimate crosses is diminished (ovule discounting). Pollinators are scarce during the flowering period, resulting in pollen limitation. It is suggested that both the scarcity of pollinators and ovule discounting may be acting synergically to promote herkogamy or its maintenance in this species. 相似文献
608.
Daniele Arobba Maria Angela Guido Paola Minale Carlo Montanari Sandra Placereani Sabrina Pracilio Costantino Troise Susanna Voltolini Arsenio Corrado Negrini 《Aerobiologia》2000,16(2):233-243
A comparison between two pollen-sampling stationsin the city area of Genoa is presented. The samplingsites are placed 3 km apart, respectively in theeastern urban area (St. Martino Hospital – S.M.) andin the historical centre (Botanical Garden – B.G.).Pollen sampling was carried out during the years1995–1997 at the two different sites by volumetricHirst-type sampler and then compared. The dailyairborne pollen concentration of Urticaceae, Poaceae,Cupressaceae/Taxaceae, Corylaceae/Betulaceae andOleaceae resulted prevailingly higher at S.M., while a good correspondence was observed from a phenologicpoint of view. Asteraceae have shown the bestqualitative-quantitative consistency. In springtime adifference was recorded for Urticales, maybe due tolocal occurence (B.G.) of Broussonetia papyrifera(Moraceae). On the whole, the correspondence betweenthe two different sampling stations proved to besatisfactory. 相似文献
609.
610.