scholarly journals Hormonal Influences on Pod–Seed Intercommunication during Pea Fruit Development

Genes ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 49
Author(s):  
Mark Bal ◽  
Lars Østergaard
Keyword(s):  
Classical Problem ◽  
Mechanical Damage ◽  
Fruit Growth ◽  
Parent Plant ◽  
Physical Barriers ◽  
Angiosperm Species ◽  
New Research ◽  
A Site ◽  
Signal Exchange ◽  
Seeds And Fruits

Angiosperms (from the Greek “angeion”—vessel, and “sperma”—seed) are defined by the presence of specialised tissue surrounding their developing seeds. This tissue is known as the ovary and once a flower has been fertilised, it gives rise to the fruit. Fruits serve various functions in relation to the seeds they contain: they often form tough physical barriers to prevent mechanical damage, they may form specialised structures that aid in dispersal, and they act as a site of nutrient and signal exchange between the parent plant and its offspring. The close coordination of fruit growth and seed development is essential to successful reproduction. Firstly, fertilisation of the ovules is required in most angiosperm species to initiate fruit growth. Secondly, it is crucial that seed dispersal facilitated by, e.g., fruit opening or ripening occurs only once the seeds have matured. These highly coordinated events suggest that seeds and fruits are in close communication throughout development and represent a classical problem of interorgan signalling and organismic resource allocation. Here, we review the contribution of studies on the edible, unicarpellate legume Pisum sativum to our understanding of seed and fruit growth coregulation, and propose areas of new research in this species which may yield important advances for both pulse agronomy and natural science.

scholarly journals The Hrq1 helicase stimulates Pso2 translesion nuclease activity to promote DNA inter-strand crosslink repair

2019 ◽  
Author(s):  
Cody M. Rogers ◽  
Chun-Ying Lee ◽  
Samuel Parkins ◽  
Nicholas J. Buehler ◽  
Sabine Wenzel ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Dna Damage Response ◽  
Nuclease Activity ◽  
Site Specific ◽  
Damage Response ◽  
Physical Barriers ◽  
A Site ◽  
Translesion Polymerases ◽  
Stimulation Of

AbstractDNA inter-strand crosslink (ICL) repair requires a complicated network of DNA damage response pathways. Removal of these lesions is vital as they are physical barriers to essential DNA processes that require the separation of duplex DNA, such as replication and transcription. The Fanconi anemia (FA) pathway is the principle mechanism for ICL repair in metazoans and is coupled to replication. In Saccharomyces cerevisiae, a degenerate FA pathway is present, but ICLs are predominantly repaired by a pathway involving the Pso2 nuclease that is hypothesized to digest through the lesion to provide access for translesion polymerases. However, Pso2 lacks translesion nuclease activity in vitro, and mechanistic details of this pathway are lacking, especially relative to FA. We recently identified the Hrq1 helicase, a homolog of the disease-linked RECQL4, as a novel component of Pso2- mediated ICL repair. Here, we show that Hrq1 stimulates the Pso2 nuclease in a mechanism that requires Hrq1 catalytic activity. Importantly, Hrq1 also stimulates Pso2 translesion nuclease activity through a site- specific ICL in vitro. Stimulation of Pso2 nuclease activity is specific to eukaryotic RecQ4 subfamily helicases, and Hrq1 likely interacts with Pso2 through their N-terminal domains. These results advance our understanding of FA-independent ICL repair and establish a role for the RecQ4 helicases in the repair of these dangerous lesions.

scholarly journals Departamento de Ecología Funcional y Aplicada, Instituto de Ecología, Universidad Nacional Autónoma de México

2017 ◽  
pp. 83
Author(s):  
Victor L. Barradas
Keyword(s):  
Energy Balance ◽  
Control Systems ◽  
Environmental Changes ◽  
Heat Fluxes ◽  
Point Of View ◽  
Net Energy ◽  
Sensible Heat ◽  
Species Establishment ◽  
Physical Barriers ◽  
A Site

<p>The deforestation of a site for agriculture and/ or cattle raising purposes changes either microclimate and soil properties. These environmental changes can act as physical barriers which drastically limits tree species establishment in reforestation . From microclimatic point of view, the study of the energy balance plays a key role when the original environment is severely changed. The net energy in a site is mainly dissipated by latent and sensible heat fluxes which are associated to evapotranspiration and thermal regimes,<br />respectively. The analyses of these fluxes allow to design control systems to reduce the high evaporation rates and high temperatures registered in a deforested site. Energy balance, latent and sensible heat fluxes and other components are analysed, and some techniques to manipulate energy balance are also presented.</p>

Scientific and Technological Challenges in RoboCup

2020 ◽  
Vol 3 (1) ◽  
pp. 441-471 ◽  
Author(s):  
Minoru Asada ◽  
Oskar von Stryk
Keyword(s):  
Research And Development ◽  
Future Research ◽  
Research Issues ◽  
Research Activities ◽  
Software Implementations ◽  
Future Research Directions ◽  
Objective View ◽  
New Research ◽  
A Site ◽  
League Structure

Since its inception in 1997, RoboCup has developed into a truly unique and long-standing research community advancing robotics and artificial intelligence through various challenges, benchmarks, and test fields. The main purposes of this article are to evaluate the research and development achievements so far and to identify new challenges and related new research issues. Unlike other robot competitions and research conferences, RoboCup eliminates the boundaries between pure research activities and the development of full system designs with hardware and software implementations at a site open to the public. It also creates specific scientific and technological research and development challenges to be addressed. In this article, we provide an overview of RoboCup, including its league structure and related research issues. We also review recent studies across several research categories to show how participants (called RoboCuppers) address the research and development challenges before, during, and after the annual competitions. Among the diversity of research issues, we highlight two unique aspects of the challenges: the platform design of the robots and the game evaluations. Both of these aspects contribute to solving the research and development challenges of RoboCup and verifying the results from a common perspective (i.e., a more objective view). Finally, we provide concluding remarks and discuss future research directions.

Breaking Ties, Building Fences

2011 ◽  
Author(s):  
Rachel St. John
Keyword(s):  
Mexican Revolution ◽  
The United States ◽  
World War ◽  
The Social ◽  
The First World War ◽  
Border Communities ◽  
Physical Barriers ◽  
A Site ◽  
Economic Ties ◽  
First World

This chapter looks at the decade of war that included both the Mexican Revolution and the United States' participation in the First World War, describing how war transformed the border from a site of interaction and cooperation to one of conflict and division—a transformation that was reflected spatially in transborder battles and the erection of border fences. During the war years, U.S. and Mexican officials began to replace the landscape of binational cooperation and conditional controls that had been developed with the countries' customs, immigration, and law enforcement needs in mind with stricter regulations on who and what could cross the border and armed men and physical barriers to enforce them. These measures, along with years of violence and bloodshed, took their toll on the social and economic ties that had bound border communities together.

The tegument in Hemiuridae (Digenea: Hemiuroidea): structure and function in the adult

1988 ◽  
Vol 62 (4) ◽  
pp. 305-316 ◽  
Author(s):  
B. F. Matthews ◽  
R. A. Matthews
Keyword(s):  
Phosphatase Activity ◽  
Mechanical Damage ◽  
Strong Acid ◽  
Structure And Function ◽  
The Body ◽  
Physico Chemical ◽  
Chemical Conditions ◽  
And Function ◽  
A Site ◽  
Outer Plasma Membrane

AbstractThe teleost stomach, as a site of strong acid proteolytic digestion at pH 1–4, is a hostile environment rarely chosen as a habitat by parasites. Several Hemiuroidea have nevertheless invaded this niche, notably the Hemiuridae, a family in which the body is characterized by a retractile “tail”, or ecsoma. The structure and function of the latter has been studied in three hemiurid species, namely Hemiurus communis, Lecithochirium rufoviride and L. fusiforme, using ultrastructural, histochemical and autoradiographic techniques. Results indicate a clear demarcation between the function of the tegument covering the ecsoma and that of the rest of the body, or soma. No mitochondria have been observed in the ecsomal tegument, and intense acid phosphatase activity was detected in association with its outer plasma membrane. Uptake of 3H-tyrosine occurred within the excretory vesicle, which may serve for transport of nutrients forwards into the soma. In contrast, the thickened, dense somal tegument, with few mitochondria largely confined to ridges or plications in H. communis, showed neither phosphatase activity nor uptake of tyrosine. Glucose uptake was not detected in any part of the body. That the somal tegument serves not for absorption but for protection against both physico-chemical conditions and mechanical damage by prey entering the host's stomach is discussed.

scholarly journals Proteome-wide and lysine crotonylation profiling reveals the importance of crotonylation in chrysanthemum (Dendranthema grandiforum) under low-temperature

2020 ◽  
Author(s):  
Ping Lin ◽  
Hui-ru Bai ◽  
Ling He ◽  
Qiu-xiang Huang ◽  
Qin-han Zeng ◽  
...  
Keyword(s):  
Low Temperature ◽  
Temperature Stress ◽  
Low Temperature Stress ◽  
Biological Information ◽  
Antioxidant Systems ◽  
Post Translational Modification ◽  
Cellular Functions ◽  
Directed Mutation ◽  
New Research ◽  
A Site

Abstract Background: Low-temperature severely affects the growth and development of chrysanthemum which is one kind of ornamental plant well-known and widely used in the world. Lysine crotonylation is a recently identified post-translational modification (PTM) with multiple cellular functions. However, lysine crotonylation under low-temperature stress has not been studied.Results: Proteome-wide and lysine crotonylation of chrysanthemum at low-temperature was analyzed using TMT (Tandem Mass Tag) labeling, sensitive immuno-precipitation, and high-resolution LC-MS/MS. The results showed that 2017 crotonylation sites were identified in 1199 proteins. Treatment at 4 °C for 24 h and −4 °C for 4 h resulted in 393 upregulated proteins and 500 downregulated proteins (1.2-fold threshold and P < 0.05). Analysis of biological information showed that lysine crotonylation was involved in photosynthesis, ribosomes, and antioxidant systems. The crotonylated proteins and motifs in chrysanthemum were compared with other plants to obtain orthologous proteins and conserved motifs. To further understand how lysine crotonylation at K136 affected APX (ascorbate peroxidase), we performed a site-directed mutation at K136 in APX. Site-directed crotonylation showed that lysine decrotonylation at K136 reduced APX activity, and lysine complete crotonylation at K136 increased APX activity.Conclusion: In summary, our study comparatively analyzed proteome-wide and crotonylation in chrysanthemum under low-temperature stress and provided insights into the mechanisms of crotonylation in positively regulated APX activity to reduce the oxidative damage caused by low-temperature stress. These data provided an important basis for studying crotonylation to regulate antioxidant enzyme activity in response to low-temperature stress and a new research ideas for chilling-tolerance and freezing-tolerance chrysanthemum molecular breeding.

scholarly journals The yeast Hrq1 helicase stimulates Pso2 translesion nuclease activity and thereby promotes DNA interstrand crosslink repair

2020 ◽  
Vol 295 (27) ◽  
pp. 8945-8957 ◽  
Author(s):  
Cody M. Rogers ◽  
Chun-Ying Lee ◽  
Samuel Parkins ◽  
Nicholas J. Buehler ◽  
Sabine Wenzel ◽  
...  
Keyword(s):  
Single Molecule ◽  
Nuclease Activity ◽  
Dna Lesions ◽  
Principal Mechanism ◽  
Single Molecule Fret ◽  
Interstrand Crosslink ◽  
Physical Barriers ◽  
A Site ◽  
Interstrand Crosslink Repair

DNA interstrand crosslink (ICL) repair requires a complex network of DNA damage response pathways. Removal of the ICL lesions is vital, as they are physical barriers to essential DNA processes that require the separation of duplex DNA, such as replication and transcription. The Fanconi anemia (FA) pathway is the principal mechanism for ICL repair in metazoans and is coupled to DNA replication. In Saccharomyces cerevisiae, a vestigial FA pathway is present, but ICLs are predominantly repaired by a pathway involving the Pso2 nuclease, which is hypothesized to use its exonuclease activity to digest through the lesion to provide access for translesion polymerases. However, Pso2 lacks translesion nuclease activity in vitro, and mechanistic details of this pathway are lacking, especially relative to FA. We recently identified the Hrq1 helicase, a homolog of the disease-linked enzyme RecQ-like helicase 4 (RECQL4), as a component of Pso2-mediated ICL repair. Here, using genetic, biochemical, and biophysical approaches, including single-molecule FRET (smFRET)– and gel-based nuclease assays, we show that Hrq1 stimulates the Pso2 nuclease through a mechanism that requires Hrq1 catalytic activity. Importantly, Hrq1 also stimulated Pso2 translesion nuclease activity through a site-specific ICL in vitro. We noted that stimulation of Pso2 nuclease activity is specific to eukaryotic RecQ4 subfamily helicases, and genetic and biochemical data suggest that Hrq1 likely interacts with Pso2 through their N-terminal domains. These results advance our understanding of FA-independent ICL repair and establish a role for the RecQ4 helicases in the repair of these detrimental DNA lesions.

scholarly journals New Perspectives on Socialism and Human Rights in East Central Europe since 1945

2019 ◽  
Vol 46 (2-3) ◽  
pp. 169-187
Author(s):  
Ned Richardson-Little ◽  
Hella Dietz ◽  
James Mark
Keyword(s):  
Human Rights ◽  
Eastern Bloc ◽  
State Socialism ◽  
East Central Europe ◽  
Post War ◽  
New Research ◽  
Human Rights History ◽  
A Site ◽  
The Cold War

In recent years, the study of human rights history has expanded beyond Western-centered narratives, though the role of Eastern European state socialism and socialists in the evolution of human rights concepts and politics has not received sufficient attention. This introductory essay synthesizes recent research of the role of Eastern Bloc socialist states in shaping the emergence of the post-war human rights system and the implications of this new research for the history of the Cold War, dissent as well as the collapse of state socialism in 1989/91. Ultimately, state socialist actors were not merely human rights antagonists, but contributed to shaping the international arena and human rights politics, motivated both strategically as well as ideologically. And the Eastern Bloc was not merely a region that passively absorbed the idea of human rights from the West, but a site where human rights ideas where articulated, internationalized and also contested.

scholarly journals Irregular migration struggles and active subjects of trans-border politics: New research strategies for interrogating the agency of the marginalised

Politics ◽  
2017 ◽  
Vol 37 (3) ◽  
pp. 243-253 ◽  
Author(s):  
Michael Strange ◽  
Vicki Squire ◽  
Anna Lundberg
Keyword(s):  
Research Agenda ◽  
Special Issue ◽  
Irregular Migration ◽  
Research Strategies ◽  
Border Politics ◽  
Irregular Migrant ◽  
New Research ◽  
A Site

The politics of migration has become increasingly prominent as a site of struggle. However, the active subjecthood of people on the move in precarious situations is often overlooked. Irregular migration struggles raise questions about how to understand the agency of people who are marginalised. What does it mean to engage people produced as ‘irregular’ as active subjects of trans-border politics? And what new research strategies can we employ to this end? The articles presented in this Special Issue of Politics each differently explore how actions by or on behalf of irregular/ised migrants involve processes of subjectivity formation that imply a form of agency. Collectively we explore how irregular migration struggles feature as a site marked by active subjects of trans-border politics. We propose a research agenda based on tracing those processes – both regulatory, activist, and everyday – that negotiate and contest how an individual is positioned as an ‘irregular migrant’. The ethos behind such research is to explore how the most marginalised individuals reclaim or reconfigure subjecthood in ambiguous terms.

scholarly journals Proteome-wide and lysine crotonylation profiling reveals the importance of crotonylation in chrysanthemum (Dendranthema grandiforum) under low-temperature

BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Ping Lin ◽  
Hui-ru Bai ◽  
Ling He ◽  
Qiu-xiang Huang ◽  
Qin-han Zeng ◽  
...  
Keyword(s):  
Low Temperature ◽  
Temperature Stress ◽  
Low Temperature Stress ◽  
Biological Information ◽  
Antioxidant Systems ◽  
Post Translational Modification ◽  
Cellular Functions ◽  
Directed Mutation ◽  
New Research ◽  
A Site

Abstract Background Low-temperature severely affects the growth and development of chrysanthemum which is one kind of ornamental plant well-known and widely used in the world. Lysine crotonylation is a recently identified post-translational modification (PTM) with multiple cellular functions. However, lysine crotonylation under low-temperature stress has not been studied. Results Proteome-wide and lysine crotonylation of chrysanthemum at low-temperature was analyzed using TMT (Tandem Mass Tag) labeling, sensitive immuno-precipitation, and high-resolution LC-MS/MS. The results showed that 2017 crotonylation sites were identified in 1199 proteins. Treatment at 4 °C for 24 h and − 4 °C for 4 h resulted in 393 upregulated proteins and 500 downregulated proteins (1.2-fold threshold and P < 0.05). Analysis of biological information showed that lysine crotonylation was involved in photosynthesis, ribosomes, and antioxidant systems. The crotonylated proteins and motifs in chrysanthemum were compared with other plants to obtain orthologous proteins and conserved motifs. To further understand how lysine crotonylation at K136 affected APX (ascorbate peroxidase), we performed a site-directed mutation at K136 in APX. Site-directed crotonylation showed that lysine decrotonylation at K136 reduced APX activity, and lysine complete crotonylation at K136 increased APX activity. Conclusion In summary, our study comparatively analyzed proteome-wide and crotonylation in chrysanthemum under low-temperature stress and provided insights into the mechanisms of crotonylation in positively regulated APX activity to reduce the oxidative damage caused by low-temperature stress. These data provided an important basis for studying crotonylation to regulate antioxidant enzyme activity in response to low-temperature stress and a new research ideas for chilling-tolerance and freezing-tolerance chrysanthemum molecular breeding.

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