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Phage-based natural selection helps identify highly specific covalent binders.
Asunto(s)
Bacteriófagos , Biblioteca de PéptidosRESUMEN
A previously identified wheat drought stress responsive Universal stress protein, TaUSP_3B-1 has been found to work in an auxin dependent manner in the plant root tissues in the differentiation zone. We also found a novel interacting partner, TaGolS, which physically interacts with TaUSP_3B-1 and colocalizes in the endoplasmic reticulum. TaGolS is a key enzyme in the RFO (Raffinose oligosaccharides) biosynthesis which is well reported to provide tolerance under water deficit conditions. TaUSP_3B-1 overexpression lines showed an early flowering phenotype under drought stress which might be attributed to the increased levels of AtTPPB and AtTPS transcripts under drought stress. Moreover, at the cellular levels ER stress induced TaUSP_3B-1 transcription and provides tolerance in both adaptive and acute ER stress via less ROS accumulation in the overexpression lines. TaUSP_3B-1 overexpression plants had increased silique numbers and a denser root architecture as compared to the WT plants under drought stress.
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Sequías , Estrés del Retículo Endoplásmico , Regulación de la Expresión Génica de las Plantas , Ácidos Indolacéticos , Proteínas de Plantas , Ácidos Indolacéticos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Estrés del Retículo Endoplásmico/fisiología , Estrés Fisiológico/genética , Triticum/genética , Triticum/fisiología , Triticum/metabolismo , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Plantas Modificadas Genéticamente , Especies Reactivas de Oxígeno/metabolismo , Retículo Endoplásmico/metabolismoRESUMEN
Phonon scattering at grain boundaries (GBs) is significant in controlling the nanoscale device thermal conductivity. However, GBs could also act as waveguides for selected modes. To measure localized GB phonon modes, milli-electron volt (meV) energy resolution is needed with subnanometer spatial resolution. Using monochromated electron energy loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM) we have mapped the 60 meV optic mode across GBs in silicon at atomic resolution and compared it to calculated phonon densities of states (DOS). The intensity is strongly reduced at GBs characterized by the presence of 5- and 7-fold rings where bond angles differ from the bulk. The excellent agreement between theory and experiment strongly supports the existence of localized phonon modes and thus of GBs acting as waveguides.
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KEY MESSAGE: TaUSPs are localized in Endoplasmic reticulum and form homo and hetero dimers within themselves. They play significant role in multiple abiotic stress responses in yeast heterologous system and in plants. Universal Stress Proteins are stress responsive proteins present in a variety of life forms ranging from bacteria to multicellular plants and animals. In this study we have identified 85 TaUSP genes in the wheat genome and have characterised their abiotic stress responsive members in yeast under different stress conditions. Localization and Y2H studies suggest that wheat, USP proteins are localized in the ER complex, and extensively crosstalk amongst themselves through forming hetero and homodimers. Expression analysis of these TaUSP genes suggests their role in adaptation to multiple abiotic stresses. TaUSP_5D-1 was found to have some DNA binding activity in yeast. Certain abiotic stress responsive TaUSP genes are found to impart tolerance to temperature stress, oxidative stress, ER stress (DTT treatment) and LiCl2 stress in the yeast heterologous system. TaUSP_5D-1 overexpression in A. thaliana imparts drought tolerance via better lateral root network in transgenic lines. The TaUSP represents an important repertoire of genes for engineering abiotic stress responsiveness in crop plants.
Asunto(s)
Proteínas de Plantas , Triticum , Triticum/genética , Triticum/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Choque Térmico/genética , Saccharomyces cerevisiae/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas/genética , SequíasRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
RESUMEN
Since it is now possible to record vibrational spectra at nanometer scales in the electron microscope, it is of interest to explore whether extended defects in crystals such as dislocations or grain boundaries will result in measurable changes of the phonon densities of states (dos) that are reflected in the spectra. Phonon densities of states were calculated for a set of high angle grain boundaries in silicon. The boundaries are modeled by supercells with up to 160 atoms, and the vibrational densities of states were calculated by taking the Fourier transform of the velocityvelocity autocorrelation function from molecular dynamics simulations with larger supercells doubled in all three directions. In selected cases, the results were checked on the original supercells by comparison with the densities of states obtained by diagonalizing the dynamical matrix calculated using density functional theory. Near the core of the grain boundary, the height of the optic phonon peak in the dos at 60 meV was suppressed relative to features due to acoustic phonons that are largely unchanged relative to their bulk values. This can be attributed to the variation in the strength of bonds in grain boundary core regions where there is a range of bond lengths.