scholarly journals Functional Association of Arabidopsis CAX1 and CAX3 Is Required for Normal Growth and Ion Homeostasis

2005 ◽  
Vol 138 (4) ◽  
pp. 2048-2060 ◽  
Author(s):  
Ning-Hui Cheng ◽  
Jon K. Pittman ◽  
Toshiro Shigaki ◽  
Jinesh Lachmansingh ◽  
Sherry LeClere ◽  
...  
Keyword(s):  
Ion Homeostasis ◽  
Normal Growth ◽  
Functional Association

scholarly journals c-di-AMP hydrolysis by a novel type of phosphodiesterase promotes differentiation of multicellular bacteria

2019 ◽  
Author(s):  
Andreas Latoscha ◽  
David Jan Drexler ◽  
Mahmoud M. Al-Bassam ◽  
Volkhard Kaever ◽  
Kim C. Findlay ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Ion Homeostasis ◽  
Normal Growth ◽  
Second Messenger ◽  
Coordinated Development ◽  
Precise Control ◽  
Rck Domain ◽  
New Type ◽  
Domain Protein ◽  
Hydrolysis Of

ABSTRACTAntibiotic-producing Streptomyces use the diadenylate cyclase DisA to synthesize the nucleotide second messenger c-di-AMP but the mechanism for terminating c-di-AMP signaling and the proteins that bind the molecule to effect signal transduction are unknown. Here, we identify the AtaC protein as a new type of c-di-AMP-specific phosphodiesterase that is also conserved in pathogens such as Streptococcus pneumoniae and Mycobacterium tuberculosis. AtaC is monomeric in solution and binds Mn2+ to specifically hydrolyze c-di-AMP to AMP via the intermediate 5’-pApA. As an effector of c-di-AMP signaling, we characterize the RCK-domain protein CpeA as the first c-di-AMP-binding protein to be identified in Streptomyces. CpeA interacts with the predicted cation / proton antiporter, CpeB, linking c-di-AMP signaling to ion homeostasis in actinobacteria. Hydrolysis of c-di-AMP is critical for normal growth and differentiation in Streptomyces, connecting osmotic stress to development. Thus, we present the discovery of two novel components of c-di-AMP signaling in bacteria and show that precise control of this second messenger is essential for osmoregulation and coordinated development in Streptomyces.

scholarly journals The Sko1p Repressor and Gcn4p Activator Antagonistically Modulate Stress-Regulated Transcription inSaccharomyces cerevisiae

2001 ◽  
Vol 21 (1) ◽  
pp. 16-25 ◽  
Author(s):  
Amparo Pascual-Ahuir ◽  
Ramón Serrano ◽  
Markus Proft
Keyword(s):  
Amino Acid ◽  
Specific Binding ◽  
Ion Homeostasis ◽  
Normal Growth ◽  
Yeast Cells ◽  
Target Sequence ◽  
Acid Uptake ◽  
Amino Acid Availability

ABSTRACT In the transcriptional response of Saccharomyces cerevisiae to stress, both activators and repressors are implicated. Here we demonstrate that the ion homeostasis determinant,HAL1, is regulated by two antagonistically operating bZIP transcription factors, the Sko1p repressor and the Gcn4p activator. A single CRE-like sequence (CRE HAL1 ) at position −222 to −215 with the palindromic core sequence TTACGTAA is essential for stress-induced expression of HAL1. Down-regulation of HAL1 under normal growth conditions requires specific binding of Sko1p to CRE HAL1 and the corepressor gene SSN6. Release from this repression depends on the function of the high-osmolarity glycerol pathway. The Gcn4p transcriptional activator binds in vitro to the same CRE HAL1 and is necessary for up-regulatedHAL1 expression in vivo, indicating a dual control mechanism by a repressor-activator pair occupying the same promoter target sequence. gcn4 mutants display a strong sensitivity to elevated K+ or Na+ concentrations in the growth medium. In addition to reduced HAL1 expression, this sensitivity is explained by the fact that amino acid uptake is drastically impaired by high Na+ and K+concentrations in wild-type yeast cells. The reduced amino acid biosynthesis of gcn4 mutants would result in amino acid deprivation. Together with the induction of HAL1 by amino acid starvation, these results suggest that salt stress and amino acid availability are physiologically interconnected.

scholarly journals c-di-AMP hydrolysis by the phosphodiesterase AtaC promotes differentiation of multicellular bacteria

2020 ◽  
Vol 117 (13) ◽  
pp. 7392-7400 ◽  
Author(s):  
Andreas Latoscha ◽  
David Jan Drexler ◽  
Mahmoud M. Al-Bassam ◽  
Adrian M. Bandera ◽  
Volkhard Kaever ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Ion Homeostasis ◽  
Normal Growth ◽  
Second Messenger ◽  
Coordinated Development ◽  
Ion Balance ◽  
Precise Control ◽  
Ionic Stress ◽  
Domain Protein ◽  
Hydrolysis Of

Antibiotic-producing Streptomyces use the diadenylate cyclase DisA to synthesize the nucleotide second messenger c-di-AMP, but the mechanism for terminating c-di-AMP signaling and the proteins that bind the molecule to effect signal transduction are unknown. Here, we identify the AtaC protein as a c-di-AMP-specific phosphodiesterase that is also conserved in pathogens such as Streptococcus pneumoniae and Mycobacterium tuberculosis. AtaC is monomeric in solution and binds Mn2+ to specifically hydrolyze c-di-AMP to AMP via the intermediate 5′-pApA. As an effector of c-di-AMP signaling, we characterize the RCK_C domain protein CpeA. c-di-AMP promotes interaction between CpeA and the predicted cation/proton antiporter, CpeB, linking c-di-AMP signaling to ion homeostasis in Actinobacteria. Hydrolysis of c-di-AMP is critical for normal growth and differentiation in Streptomyces, connecting ionic stress to development. Thus, we present the discovery of two components of c-di-AMP signaling in bacteria and show that precise control of this second messenger is essential for ion balance and coordinated development in Streptomyces.

New Ultrastructural Observations on Injury and Regeneration of Cilia in Mammalian Conducting Airway Epithelium

1981 ◽  
Vol 39 ◽  
pp. 624-625
Author(s):  
J.L. Carson ◽  
A.M. Collier
Keyword(s):  
Respiratory Tract ◽  
Airway Epithelium ◽  
Defense Mechanisms ◽  
Normal Growth ◽  
Fetal Lung ◽  
Secretory Cells ◽  
Airway Epithelial ◽  
Ciliated Cells ◽  
Conducting Airway ◽  
Conducting Airways

The ciliated cells lining the conducting airways of mammals are integral to the defense mechanisms of the respiratory tract, functioning in coordination with secretory cells in the removal of inhaled and cellular debris. The effects of various infectious and toxic agents on the structure and function of airway epithelial cell cilia have been studied in our laboratory, both of which have been shown to affect ciliary ultrastructure.These observations have led to questions about ciliary regeneration as well as the possible induction of ciliogenesis in response to cellular injury. Classical models of ciliogenesis in the conducting airway epithelium of the mammalian respiratory tract have been based primarily on observations of the developing fetal lung. These observations provide a plausible explanation for the embryological generation of ciliary beds lining the conducting airways but do little to account for subsequent differentiation of ciliated cells and ciliogenesis during normal growth and development.

Crisis Management under Economic Sanctions: Mission Impossible?

2015 ◽  
pp. 20-36 ◽  
Author(s):  
S. Afontsev
Keyword(s):  
Crisis Management ◽  
Import Substitution ◽  
Normal Growth ◽  
Economic Sanctions ◽  
Public And Private ◽  
Technology Markets ◽  
Economic Relations ◽  
Russian Economy ◽  
Wide Scale ◽  
Trade Partners

Economic sanctions against Russia form a completely new context for public and private efforts to cope with crisis trends in Russian economy. With limited access to global goods, capital, and technology markets, it can at best minimize costs of the crisis but not come back to the normal growth path. Strategies to find new trade partners and sources of capital outside the group of countries that have introduced economic sanctions against Russia are welcome, but their potential is rather limited. Under these circumstances, crisis management should be centered neither on the alleged ‘Russia’s pivot to the East’ nor on the wide-scale import substitution but on normalization of economic relations with key country partners, regaining currency stability, and structural reforms aimed at moving national economy away from commodity specialization.

Relevance of enrichment of landscaping plantings with lianas in the conditions of urban ecosystems of the Saratov region

2019 ◽  
pp. 21-38
Author(s):  
А.В. Терешкин ◽  
А.Л. Калмыкова ◽  
Т.А. Андрушко
Keyword(s):  
Species Composition ◽  
Urban Areas ◽  
Normal Growth ◽  
Steppe Zone ◽  
Climatic Conditions ◽  
Phaseolus Coccineus ◽  
Morning Glory ◽  
Forest Steppe ◽  
Residential Areas ◽  
Saratov Region

Вертикальное озеленение с участием различных видов лиан в современных условиях имеет важное эстетическое и санитарно-гигиеническое значение. Особо актуально решение вопросов обогащения флоры городских территорий лианами в степных районах в связи с бедным видовым составом и резким ухудшением экологической ситуации. Объектами исследований являлись 7 видов лиан, различных жизненных форм (однолетние, многолетние), произрастающие в населенных пунктах Саратовской области (Аткарск, Саратов). Цель исследований – изучение эколого-биологических особенностей и мелиоративных свойств лиан и выявление перспектив их использования в вертикальном озеленении селитебных территорий Саратовской области. В ходе исследования видового состава, были выявлены наиболее популярные виды однолетних лиан: ипомея красно-голубая (Ipomea tricolor (L.) Roth) и ипомея пурпурная (Ipomea purpurea (L.) Roth), горошек душистый (Lathyrus edoratus L.), настурция (Tropacolum peregrinum L.) и фасоль огненно-красная (Phaseolus coccineus). Большинство (70%) из них произрастают в местах ограниченного пользования. Изученные виды лиан в исследуемых регионах достигают средних природных показателей (при наличии надлежащего ухода), обладают хорошими показателями жизненного состояния, обильно цветут и плодоносят. При воздействии токсикантами различной концентрации на листовые пластинки лиан установлено их степень устойчивости. Выявлено, что однолетние лианы лучше использовать в декоративных целях, а не в санитарно-гигиенических. Сравнительная оценка однолетних видов с многолетними лианами (девичий виноград пятилисточковый и клематис тангутский) показывает устойчивость многолетних видов (в среднем на 3 балла - 40%). Разработаны варианты декоративных композиций с участием травянистых лиан. По степени декоративности выделены однолетние лианы – Ipomea tricolor, I. purpurea (37 – 41 балл), средней степенью отличаются – Lathyrus edoratus (33 балла), Tropacolum peregrinum (30 баллов) и Phaseolus coccineus (20 – 27 баллов). Преимущество многолетних лиан заключается в их устойчивости к резким изменениям климатических условий (на 40 %) по сравнению с однолетними формами. Поэтому они более предпочтительны для озеленения городской среды. Для усиления декоративного эффекта в сезонном аспекте рекомендуются сочетать расширение видового и формового разнообразия растений (многолетние и однолетние лианы, древесно-кустарниковая, цветочная растительность). Установлено, что природно-климатические условия зоны степи и лесостепи в пределах Саратовской области являются достаточно благоприятными для нормального роста и развития древесно-кустарниковой растительности, в том числе травянистых лиан. Таким образом, обоснованное применение древесных лиан в комплексе с традиционными видами насаждений позволит создать комфортные условия проживания населения, регулировать оптимальный температурный баланс и создавать благоприятные микроклиматические условия. Vertical gardening with different types of vines in modern conditions is important aesthetic and sanitary-hygienic value. It is especially important to address the issues of enrichment of the flora of urban areas with vines in the steppe regions due to poor species composition and a sharp deterioration of the ecological situation. The objects of research were 7 species of lianas, various life forms (annual, perennial), growing in the settlements of the Saratov region (Atkarsk, Saratov). The aim of the research is to study the ecological and biological features and reclamation properties of vines and identify the prospects for their use in vertical gardening residential areas of the Saratov region. In the study, species composition was the most popular species of annual vines: morning glory red-blue (Ipomea tricolor (L.) Roth) and purple morning glory (Ipomea purpurea (L.) Roth), the fragrant pea (Lathyrus edoratus L.), nasturtium (Tropacolum peregrinum L.) and runner beans (Phaseolus coccineus). Most (70%) of them grow in restricted areas. Studied species of vines in the study regions reach average natural performance (with proper care), have good indicators of vital condition, bloom abundantly and bear fruit. When exposed to toxicants of different concentrations on the leaf blades of vines established their degree of stability. It was revealed that the annual vines are better used for decorative purposes, and not in the sanitary-hygienic. A comparative assessment of annual species with perennial vines (maiden grapes and clematis Tangut) shows the stability of perennial species (an average of 3 points-40%). The options and decorative compositions with the participation of herbaceous vines. According to the degree of decoration of the allocated annual vine – Ipomea tricolor, I. purpurea (37 – 41 points), the average degree of differ – Lathyrus edoratus (33 points), Tropacolum peregrinum (30 points) and Phaseolus coccineus (20 to 27 points). The advantage of perennial vines is their resistance to sudden changes in climatic conditions (40 %) compared to annual forms. Therefore, they are more preferable for greening the urban environment. To enhance the decorative effect in the seasonal aspect, it is recommended to combine the expansion of species and form diversity of plants (perennial and annual lianas, tree and shrub, floral vegetation). It is established that the climatic conditions of the steppe and forest-steppe zone within the Saratov region are quite favorable for the normal growth and development of tree and shrub vegetation, including herbaceous lianas. Thus, the reasonable use of wood vines in combination with traditional types of plantings will create comfortable living conditions for the population, regulate the optimal temperature balance and create favorable microclimatic conditions.

CREATION OF THE INDUCED APPLE-THREE TETRAPLOIDS

1970 ◽  
pp. 23-25
Author(s):  
L. V. Tashmatova ◽  
О. V. Mantseva ◽  
N. V. Gorbacheva
Keyword(s):  
Environmental Conditions ◽  
Selection Process ◽  
Normal Growth ◽  
Cytological Analysis ◽  
Open Pollination ◽  
Apple Breeding ◽  
Adverse Environmental Conditions ◽  
Diploid Gametes ◽  
Resistance To Diseases

The basic moments of a process of obtaining apple tetraploids as donors of diploid gametes for apple breeding with polyploidy using are demonstrated. In industrial terms, triploids are of the greatest importance. The manifested effect of heterosis leads to the improvement of many characteristics - higher resistance to diseases, pests and adverse environmental conditions, greater autogamy than in diploids, less pronounced periodicity of fruiting, larger fruits and a convenient crown for harvesting. Triploids are developed as a result of crosses 2n × 3n or 2n × 4n. Tetraploids are necessary for more successful apple breeding with polyploidy using. For industry they are not of great importance but they are of interest as donors of diploid non-reduced gametes and allow to make the selection process more directional. One of the methods of experimental polyploidy is the induction of polyploids using mutagenes. The germs were treated with colchicines at concentrations 0.1% - 0.4% during 24 and 48 hours. According to the morphology the obtained plants were divided into five groups. Colchicine concentrations 0.3% and 0.4% during 48 hours of the treatment had a disastrous impact on the development of germs. As a result of the cytological analysis, tetraploids and chimeras were revealed, which were obtained from the seeds from the open pollination of Orlik and Svezhest (treatment variants – 0,1% colchicines solution and 24 and 48 hours of exposition), as well as from the seeds obtained as a result of the Svezhest × Bolotovskoye crossing. Tetraploids had a normal growth but they differed in large leaves, while chimeras were of low size with normal leaves and internodes.

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