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981.
Hasna Ellouzi Karim Ben Hamed Iker Hernández Jana Cela Maren Müller Christian Magné Chedly Abdelly Sergi Munné-Bosch 《Planta》2014,240(6):1299-1317
Salt stress is one of the most important abiotic stress factors affecting plant growth and productivity in natural ecosystems. In this study, we aimed at determining possible differences between salt tolerant and salt sensitive species in early (within 72 h) salt stress response in leaves and roots. To this purpose, we subjected three Brassicaceae species, namely two halophytes—Cakile maritima and Thellungiella salsuginea—and a glycophyte—Arabidopsis thaliana— to short-term salt stress (400 mM NaCl). The results indicate that the halophytes showed a differential osmotic and ionic response together with an early and transient oxidative burst, which was characterized by enhanced hydrogen peroxide levels and subsequent activation of antioxidant defenses in both leaves and roots. In addition, the halophytes displayed enhanced accumulation of abscisic acid, jasmonic acid (JA) and ACC (aminocyclopropane-1-carboxylic acid, the precursor of ethylene) in leaves and roots, as compared to A. thaliana under salt stress. Moreover, the halophytes showed enhanced expression of ethylene response factor1 (ERF1), the convergence node of the JA and ethylene signaling pathways in both leaves and roots upon exposure to salt stress. In conclusion, we show that the halophytes C. maritima and T. salsuginea experience an early oxidative burst, improved antioxidant defenses and hormonal response not only in leaves but also in roots, in comparison to the glycophyte A. thaliana. This differential signaling response converging, at least in part, into increased ERF1 expression in both above- and underground tissues seems to underlay, at least in part, the enhanced tolerance of the two studied halophytes to salt stress. 相似文献
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984.
Allosteric Inhibitors of the Eya2 Phosphatase Are Selective and Inhibit Eya2-mediated Cell Migration
Aaron B. Krueger David J. Drasin Wendy A. Lea Aaron N. Patrick Samarjit Patnaik Donald S. Backos Christopher J. Matheson Xin Hu Elena Barnaeva Michael J. Holliday Melanie A. Blevins Tyler P. Robin Elan Z. Eisenmesser Marc Ferrer Anton Simeonov Noel Southall Philip Reigan Juan Marugan Heide L. Ford Rui Zhao 《The Journal of biological chemistry》2014,289(23):16349-16361
985.
Ingrid Vilagran Marc Yeste Sílvia Sancho Isabel Casas Maria M. Rivera del Álamo Sergi Bonet 《Theriogenology》2014
Freezability differences between boar ejaculates exist, but there is no useful method to predict the ejaculate freezability before sperm cryopreservation takes place. In this context, the present study sought to determine whether the amounts of small heat-shock protein 10 (also known as outer dense fiber protein 1) (ODF1/HSPB10) and voltage-dependent anion channel 2 (VDAC2) may be used as boar sperm freezability markers. With this aim, 26 boar ejaculates were split into two fractions: one for protein extraction and the other for cryopreservation purposes. Ejaculates were subsequently classified into two groups (good freezability ejaculates [GFE] and poor freezability ejaculates [PFE]) based on viability and sperm motility assessments after 30 and 240 minutes of after thawing. Although the VDAC2 amounts, analyzed through Western blot, were significantly higher (P < 0.01) in GFE (1.15 ± 0.18 density mm2) than in PFE (0.16 ± 0.03 density mm2), no significant differences were observed in ODF1/HSPB10 between both groups (i.e., 1.97 ± 0.38 density mm2 in GFE vs. 1.87 ± 1.54 density mm2 in PFE). In addition, principal component and multiple regression analyses indicated that the component explaining most of the variance (78.41%) in ejaculate freezability at 240 minutes after thawing resulted to be significantly (P < 0.05) correlated with VDAC2 content. This result revealed that the amounts of VDAC2 but not those of ODF1/HSPB10 may be used to predict the freezability of a given boar ejaculate before starting cryopreservation procedures. 相似文献
986.
Marie Foulongne-Oriol Nicolas Lapalu Cyril Férandon Cathy Spataro Nathalie Ferrer Joelle Amselem Jean-Michel Savoie 《Applied microbiology and biotechnology》2014,98(18):7879-7892
Agaricus subrufescens is one of the most important culinary-medicinal cultivable mushrooms with potentially high-added-value products and extended agronomical valorization. The development of A. subrufescens-related technologies is hampered by, among others, the lack of suitable molecular tools. Thus, this mushroom is considered as a genomic orphan species with a very limited number of available molecular markers or sequences. To fill this gap, this study reports the generation and analysis of the first set of expressed sequence tags (EST) for A. subrufescens. cDNA fragments obtained from young sporophores (SP) and vegetative mycelium in liquid culture (CL) were sequenced using 454 pyrosequencing technology. After assembly process, 4,989 and 5,125 sequences were obtained in SP and CL libraries, respectively. About 87 % of the EST had significant similarity with Agaricus bisporus-predicted proteins, and 79 % correspond to known proteins. Functional categorization according to Gene Ontology could be assigned to 49 % of the sequences. Some gene families potentially involved in bioactive compound biosynthesis could be identified. A total of 232 simple sequence repeats (SSRs) were identified, and a set of 40 EST-SSR polymorphic markers were successfully developed. This EST dataset provides a new resource for gene discovery and molecular marker development. It constitutes a solid basis for further genetic and genomic studies in A. subrufescens. 相似文献
987.
Nerea Sanvisens Antonia M. Romero Xiuxiang An Caiguo Zhang Rosa de Llanos María Teresa Martínez-Pastor M. Carmen Ba?ó Mingxia Huang Sergi Puig 《Molecular and cellular biology》2014,34(17):3259-3271
Iron is an essential micronutrient for all eukaryotic organisms because it participates as a redox-active cofactor in many biological processes, including DNA replication and repair. Eukaryotic ribonucleotide reductases (RNRs) are Fe-dependent enzymes that catalyze deoxyribonucleoside diphosphate (dNDP) synthesis. We show here that the levels of the Sml1 protein, a yeast RNR large-subunit inhibitor, specifically decrease in response to both nutritional and genetic Fe deficiencies in a Dun1-dependent but Mec1/Rad53- and Aft1-independent manner. The decline of Sml1 protein levels upon Fe starvation depends on Dun1 forkhead-associated and kinase domains, the 26S proteasome, and the vacuolar proteolytic pathway. Depletion of core components of the mitochondrial iron-sulfur cluster assembly leads to a Dun1-dependent diminution of Sml1 protein levels. The physiological relevance of Sml1 downregulation by Dun1 under low-Fe conditions is highlighted by the synthetic growth defect observed between dun1Δ and fet3Δ fet4Δ mutants, which is rescued by SML1 deletion. Consistent with an increase in RNR function, Rnr1 protein levels are upregulated upon Fe deficiency. Finally, dun1Δ mutants display defects in deoxyribonucleoside triphosphate (dNTP) biosynthesis under low-Fe conditions. Taken together, these results reveal that the Dun1 checkpoint kinase promotes RNR function in response to Fe starvation by stimulating Sml1 protein degradation. 相似文献
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Daniele R. Contin Hilda H. Soriani Iker Hernández Rosa P. M. Furriel Sergi Munné-Bosch Carlos A. Martinez 《Trees - Structure and Function》2014,28(6):1705-1722