scholarly journals Plant HKT Channels: An Updated View on Structure, Function and Gene Regulation

2021 ◽  
Vol 22 (4) ◽  
pp. 1892 ◽  
Author(s):  
Janin Riedelsberger ◽  
Julia K. Miller ◽  
Braulio Valdebenito-Maturana ◽  
Miguel A. Piñeros ◽  
Wendy González ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Salt Tolerance ◽  
Molecular Level ◽  
Sequence Polymorphism ◽  
High Complexity ◽  
K Uptake ◽  
Short Term ◽  
Na Uptake ◽  
Starvation Conditions

HKT channels are a plant protein family involved in sodium (Na+) and potassium (K+) uptake and Na+-K+ homeostasis. Some HKTs underlie salt tolerance responses in plants, while others provide a mechanism to cope with short-term K+ shortage by allowing increased Na+ uptake under K+ starvation conditions. HKT channels present a functionally versatile family divided into two classes, mainly based on a sequence polymorphism found in the sequences underlying the selectivity filter of the first pore loop. Physiologically, most class I members function as sodium uniporters, and class II members as Na+/K+ symporters. Nevertheless, even within these two classes, there is a high functional diversity that, to date, cannot be explained at the molecular level. The high complexity is also reflected at the regulatory level. HKT expression is modulated at the level of transcription, translation, and functionality of the protein. Here, we summarize and discuss the structure and conservation of the HKT channel family from algae to angiosperms. We also outline the latest findings on gene expression and the regulation of HKT channels.

Cellular and molecular neuroscience of alcoholism

1997 ◽  
Vol 77 (1) ◽  
pp. 1-20 ◽  
Author(s):  
I. Diamond ◽  
A. S. Gordon
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Molecular Level ◽  
Cellular Functions ◽  
Short Term ◽  
Medical Disorders ◽  
Molecular Neuroscience ◽  
Long Term Changes ◽  
The Brain

Recent advances in neuroscience have made it possible to investigate the pathophysiology of alcoholism at a cellular and molecular level. Evidence indicates that ethanol affects hormone- and neurotransmitter-activated signal transduction, leading to short-term changes in regulation of cellular functions and long-term changes in gene expression. Such changes in the brain probably underlie many of the acute and chronic neurological events in alcoholism. In addition, genetic vulnerability also plays a role in alcoholism and, perhaps, in alcoholic medical disorders.

scholarly journals Arabidopsis heat shock transcription factor HSFA7b positively mediates salt stress tolerance by binding to an E-box-like motif to regulate gene expression

2019 ◽  
Vol 70 (19) ◽  
pp. 5355-5374 ◽  
Author(s):  
Dandan Zang ◽  
Jingxin Wang ◽  
Xin Zhang ◽  
Zhujun Liu ◽  
Yucheng Wang
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Heat Shock ◽  
Salt Tolerance ◽  
Stress Responses ◽  
Ion Homeostasis ◽  
Cellulose Synthase ◽  
Regulate Gene Expression ◽  
E Box ◽  
Regulate Gene

Abstract Plant heat shock transcription factors (HSFs) are involved in heat and other abiotic stress responses. However, their functions in salt tolerance are little known. In this study, we characterized the function of a HSF from Arabidopsis, AtHSFA7b, in salt tolerance. AtHSFA7b is a nuclear protein with transactivation activity. ChIP-seq combined with an RNA-seq assay indicated that AtHSFA7b preferentially binds to a novel cis-acting element, termed the E-box-like motif, to regulate gene expression; it also binds to the heat shock element motif. Under salt conditions, AtHSFA7b regulates its target genes to mediate serial physiological changes, including maintaining cellular ion homeostasis, reducing water loss rate, decreasing reactive oxygen species accumulation, and adjusting osmotic potential, which ultimately leads to improved salt tolerance. Additionally, most cellulose synthase-like (CSL) and cellulose synthase (CESA) family genes were inhibited by AtHSFA7b; some of them were randomly selected for salt tolerance characterization, and they were mainly found to negatively modulate salt tolerance. By contrast, some transcription factors (TFs) were induced by AtHSFA7b; among them, we randomly identified six TFs that positively regulate salt tolerance. Thus, AtHSFA7b serves as a transactivator that positively mediates salinity tolerance mainly through binding to the E-box-like motif to regulate gene expression.

scholarly journals Base-Pair Opening Dynamics Study of Fluoride Riboswitch in the Bacillus cereus CrcB Gene

2021 ◽  
Vol 22 (6) ◽  
pp. 3234
Author(s):  
Juhyun Lee ◽  
Si-Eun Sung ◽  
Janghyun Lee ◽  
Jin Young Kang ◽  
Joon-Hwa Lee ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Nmr Spectroscopy ◽  
Bacillus Cereus ◽  
Base Pair ◽  
Noncoding Rna ◽  
Hydrogen Exchange ◽  
Magnesium Ion ◽  
Fluoride Ion ◽  
Base Pair Opening

Riboswitches are segments of noncoding RNA that bind with metabolites, resulting in a change in gene expression. To understand the molecular mechanism of gene regulation in a fluoride riboswitch, a base-pair opening dynamics study was performed with and without ligands using the Bacillus cereus fluoride riboswitch. We demonstrate that the structural stability of the fluoride riboswitch is caused by two steps depending on ligands. Upon binding of a magnesium ion, significant changes in a conformation of the riboswitch occur, resulting in the greatest increase in their stability and changes in dynamics by a fluoride ion. Examining hydrogen exchange dynamics through NMR spectroscopy, we reveal that the stabilization of the U45·A37 base-pair due to the binding of the fluoride ion, by changing the dynamics while maintaining the structure, results in transcription regulation. Our results demonstrate that the opening dynamics and stabilities of a fluoride riboswitch in different ion states are essential for the genetic switching mechanism.

scholarly journals CFTR Cooperative Cis-Regulatory Elements in Intestinal Cells

2021 ◽  
Vol 22 (5) ◽  
pp. 2599
Author(s):  
Mégane Collobert ◽  
Ozvan Bocher ◽  
Anaïs Le Nabec ◽  
Emmanuelle Génin ◽  
Claude Férec ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cystic Fibrosis ◽  
Gene Regulation ◽  
Genetic Diseases ◽  
Regulatory Elements ◽  
Cftr Gene ◽  
Intestinal Cells ◽  
Cooperative Effects ◽  
Cis Acting ◽  
Study Techniques

About 8% of the human genome is covered with candidate cis-regulatory elements (cCREs). Disruptions of CREs, described as “cis-ruptions” have been identified as being involved in various genetic diseases. Thanks to the development of chromatin conformation study techniques, several long-range cystic fibrosis transmembrane conductance regulator (CFTR) regulatory elements were identified, but the regulatory mechanisms of the CFTR gene have yet to be fully elucidated. The aim of this work is to improve our knowledge of the CFTR gene regulation, and to identity factors that could impact the CFTR gene expression, and potentially account for the variability of the clinical presentation of cystic fibrosis as well as CFTR-related disorders. Here, we apply the robust GWAS3D score to determine which of the CFTR introns could be involved in gene regulation. This approach highlights four particular CFTR introns of interest. Using reporter gene constructs in intestinal cells, we show that two new introns display strong cooperative effects in intestinal cells. Chromatin immunoprecipitation analyses further demonstrate fixation of transcription factors network. These results provide new insights into our understanding of the CFTR gene regulation and allow us to suggest a 3D CFTR locus structure in intestinal cells. A better understand of regulation mechanisms of the CFTR gene could elucidate cases of patients where the phenotype is not yet explained by the genotype. This would thus help in better diagnosis and therefore better management. These cis-acting regions may be a therapeutic challenge that could lead to the development of specific molecules capable of modulating gene expression in the future.

Short-term Load Forecasting by Using Improved GEP and Abnormal Load Recognition

2021 ◽  
Vol 21 (4) ◽  
pp. 1-28
Author(s):  
Song Deng ◽  
Fulin Chen ◽  
Xia Dong ◽  
Guangwei Gao ◽  
Xindong Wu
Keyword(s):  
Gene Expression ◽  
Probability Distribution ◽  
Detection Rate ◽  
Cross Validation ◽  
Normal Load ◽  
Gene Expression Programming ◽  
Load Forecasting ◽  
Short Term ◽  
Forecasting Models ◽  
Short Term Load Forecasting

Load forecasting in short term is very important to economic dispatch and safety assessment of power system. Although existing load forecasting in short-term algorithms have reached required forecast accuracy, most of the forecasting models are black boxes and cannot be constructed to display mathematical models. At the same time, because of the abnormal load caused by the failure of the load data collection device, time synchronization, and malicious tampering, the accuracy of the existing load forecasting models is greatly reduced. To address these problems, this article proposes a Short-Term Load Forecasting algorithm by using Improved Gene Expression Programming and Abnormal Load Recognition (STLF-IGEP_ALR). First, the Recognition algorithm of Abnormal Load based on Probability Distribution and Cross Validation is proposed. By analyzing the probability distribution of rows and columns in load data, and using the probability distribution of rows and columns for cross-validation, misjudgment of normal load in abnormal load data can be better solved. Second, by designing strategies for adaptive generation of population parameters, individual evolution of populations and dynamic adjustment of genetic operation probability, an Improved Gene Expression Programming based on Evolutionary Parameter Optimization is proposed. Finally, the experimental results on two real load datasets and one open load dataset show that compared with the existing abnormal data detection algorithms, the algorithm proposed in this article have higher advantages in missing detection rate, false detection rate and precision rate, and STLF-IGEP_ALR is superior to other short-term load forecasting algorithms in terms of the convergence speed, MAE, MAPE, RSME, and R 2 .

scholarly journals Na+ Transporter SvHKT1;1 from a Halophytic Turf Grass Is Specifically Upregulated by High Na+ Concentration and Regulates Shoot Na+ Concentration

2020 ◽  
Vol 21 (17) ◽  
pp. 6100
Author(s):  
Yuki Kawakami ◽  
Shahin Imran ◽  
Maki Katsuhara ◽  
Yuichi Tada
Keyword(s):  
Salt Stress ◽  
Salt Tolerance ◽  
Early Stage ◽  
Constitutive Expression ◽  
Xenopus Laevis Oocytes ◽  
Na Transport ◽  
Turf Grass ◽  
Defective Mutant ◽  
Reduced Salt ◽  
Na Uptake

We characterized an Na+ transporter SvHKT1;1 from a halophytic turf grass, Sporobolus virginicus. SvHKT1;1 mediated inward and outward Na+ transport in Xenopus laevis oocytes and did not complement K+ transporter-defective mutant yeast. SvHKT1;1 did not complement athkt1;1 mutant Arabidopsis, suggesting its distinguishable function from other typical HKT1 transporters. The transcript was abundant in the shoots compared with the roots in S. virginicus and was upregulated by severe salt stress (500 mM NaCl), but not by lower stress. SvHKT1;1-expressing Arabidopsis lines showed higher shoot Na+ concentrations and lower salt tolerance than wild type (WT) plants under nonstress and salt stress conditions and showed higher Na+ uptake rate in roots at the early stage of salt treatment. These results suggested that constitutive expression of SvHKT1;1 enhanced Na+ uptake in root epidermal cells, followed by increased Na+ transport to shoots, which led to reduced salt tolerance. However, Na+ concentrations in phloem sap of the SvHKT1;1 lines were higher than those in WT plants under salt stress. Based on this result, together with the induction of the SvHKT1;1 transcription under high salinity stress, it was suggested that SvHKT1;1 plays a role in preventing excess shoot Na+ accumulation in S. virginicus.

scholarly journals Regulation and imaging of gene expression via an RNA interference antagonistic biomimetic probe

2017 ◽  
Vol 8 (7) ◽  
pp. 4973-4977 ◽  
Author(s):  
Kai Zhang ◽  
Xue-Jiao Yang ◽  
Wei Zhao ◽  
Ming-Chen Xu ◽  
Jing-Juan Xu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Rna Interference ◽  
Living Cells

A versatile strategy is reported which permits gene regulation and imaging in living cells via an RNA interference antagonistic probe.

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