Research progress of the Elongator complex in plant

The Elongator complex consists of six subunits (ELP1-ELP6), where ELP1-ELP3 forms the core subcomplex and ELP4-ELP6 forms the auxiliary subcomplex. Deletion of any of the six subunits results in an almost identical phenotype, suggesting that all six subunits are essential for cellular function. All six subunits are evolutionarily conserved in terms of sequence and their interactions with other subunits. The most striking features are the structural conservation of the protein complexes and the phenotypic similarity caused by loss-of-function mutations in any protein subunit. Similar to elongation factors in translation, there is a strong interaction between the Elongator complex and RNA polymerase II during transcription. The Elongator complex is also involved in a variety of cellular pathways, including histone modification/acetylation, DNA methylation, tRNA nucleoside modification, etc. Here, we summarized the functions and mechanisms of the Elongator complex in plant growth and development, molecular pathways, and gene regulation. In this way, we aimed to provide a reference for an in-depth study of the Elongator complex

The binding pocket properties were fundamental to functional diversification of the GDSL-type esterases/lipases gene family in cotton

Cotton is one of the most important crops in the world. GDSL-type esterases/lipases (GELPs) are widely present in all kingdoms and play an essential role in regulating plant growth, development, and responses to abiotic and biotic stresses. However, the molecular mechanisms underlying this functional diversity remain unclear. Here, based on the identification of the GELP gene family, we applied genetic evolution and molecular simulation techniques to explore molecular mechanisms in cotton species. A total of 1502 GELP genes were identified in 10 cotton species. Segmental duplication and differences in evolutionary rates are the leading causes of the increase in the number and diversity of GELP genes during evolution for ecological adaptation. Structural analysis revealed that the GELP family has high structural diversity. Moreover, molecular simulation studies have demonstrated significant differences in the properties of the binding pockets among cotton GELPs. In the process of adapting to the environment, GELPs not only have segmental duplication but also have different evolutionary rates, resulting in gene diversity. This diversity leads to significant differences in the 3D structure and binding pocket properties and, finally, to functional diversity. These findings provide a reference for further functional analyses of plant GELPs

Onset mechanism of an inverted U-shaped solar filament eruption revealed by NVST, SDO, and STEREO-A observations

Utilizing observations from the New Vacuum Solar Telescope (NVST), Solar Dynamics Observatory (SDO), and Solar Terrestrial Relations Observatory-Ahead (STEREO-A), we investigate the event from two distinct observational perspectives: on the solar disk using NVST and SDO, and on the solar limb using STEREO-A. We employ both a non-linear force-free field model and a potential field model to reconstruct the coronal magnetic field, aiming to understand its magnetic properties. Two precursor jet-like activities were observed before the eruption, displaying an untwisted rotation. The second activity released an estimated twist of over two turns. During these two jet-like activities, Y-shaped brightenings, newly emerging magnetic flux accompanied by magnetic cancellation, and the formation of newly moving fibrils were identified. Combining these observational features, it can be inferred that these two precursor jet-like activities released the magnetic field constraining the filament and were triggered by newly emerging magnetic flux. Before the filament eruption, it was observed that some moving flows had been ejected from the site as the onset of two jet-like activities, indicating the same physical process as two jet-like activities. Extrapolations revealed that the filament laid under the height of the decay index of 1.0 and had strong magnetic field (540 Gauss) and a high twisted number (2.4 turns) before the eruption. An apparent rotational motion was observed during the filament eruption. We deduce that the solar filament, exhibiting an inverted U-shape, is a significantly twisted flux rope. The eruption of the filament was initiated by the release of constraining magnetic fields through continuous magnetic reconnection. This reconnection process was triggered by the emergence of newly magnetic flux.Comment: 18 pages, 12 figures, accepted for publication in Astronomy & Astrophysic

Human Fetal Liver Stromal Cells That Overexpress bFGF Support Growth and Maintenance of Human Embryonic Stem Cells

In guiding hES cell technology toward the clinic, one key issue to be addressed is to culture and maintain hES cells much more safely and economically in large scale. In order to avoid using mouse embryonic fibroblasts (MEFs) we isolated human fetal liver stromal cells (hFLSCs) from 14 weeks human fetal liver as new human feeder cells. hFLSCs feeders could maintain hES cells for 15 passages (about 100 days). Basic fibroblast growth factor (bFGF) is known to play an important role in promoting self-renewal of human embryonic stem (hES) cells. So, we established transgenic hFLSCs that stably express bFGF by lentiviral vectors. These transgenic human feeder cells — bFGF-hFLSCs maintained the properties of H9 hES cells without supplementing with any exogenous growth factors. H9 hES cells culturing under these conditions maintained all hES cell features after prolonged culture, including the developmental potential to differentiate into representative tissues of all three embryonic germ layers, unlimited and undifferentiated proliferative ability, and maintenance of normal karyotype. Our results demonstrated that bFGF-hFLSCs feeder cells were central to establishing the signaling network among bFGF, insulin-like growth factor 2 (IGF-2), and transforming growth factor β (TGF-β), thereby providing the framework in which hES cells were instructed to self-renew or to differentiate. We also found that the conditioned medium of bFGF-hFLSCs could maintain the H9 hES cells under feeder-free conditions without supplementing with bFGF. Taken together, bFGF-hFLSCs had great potential as feeders for maintaining pluripotent hES cell lines more safely and economically

SemEval-2010 task 18: disambiguating sentiment ambiguous adjectives

Sentiment ambiguous adjectives, which have been neglected by most previous researches, pose a challenging task in sentiment analysis. We present an evaluation task at SemEval-2010, designed to provide a framework for comparing different approaches on this problem. The task focuses on 14 Chinese sentiment ambiguous adjectives, and provides manually labeled test data. There are 8 teams submitting 16 systems in this task. In this paper, we define the task, describe the data creation, list the participating systems, and discuss different approaches.Computer Science, Interdisciplinary ApplicationsSCI(E)1ARTICLE3,SI743-7554

Improved word similarity computation for Chinese using sub-word information

In the Chinese language, words consist of characters each of which is composed of one or more components. Almost every individual Chinese character has a specific meaning, and the meaning of a word is usually highly related to the characters that comprise it. Likewise, sub-character components often make a predictable contribution to the meaning of a character, and in general characters that have the same components have similar or related meanings. It is easy to automatically decompose words into characters and their components. In this paper, we improve on a corpus-based approach to computing word similarity in Chinese by extending it according to the characters and components shared between words. In an evaluation on 30,000 word types (noun, verb and adjective), we obtain a 39% relative improvement compared with a state-of-the-art baseline