SEARCHING AND MINING VISUALLY OBSERVED PHENOTYPES OF MAIZE MUTANTS

2007 ◽  
Vol 05 (06) ◽  
pp. 1193-1213 ◽  
Author(s):  
CHI-REN SHYU ◽  
JATURON HARNSOMBURANA ◽  
JASON GREEN ◽  
ADRIAN S. BARB ◽  
TONI KAZIC ◽  
...  
Keyword(s):  
Cell Biology ◽  
Species Conservation ◽  
Genetic Maps ◽  
Cell Physiology ◽  
Complex Processes ◽  
Intimate Knowledge ◽  
Scientific Challenge ◽  
Underlying Mechanisms ◽  
Mutant Phenotypes ◽  
High Level

There are thousands of maize mutants, which are invaluable resources for plant research. Geneticists use them to study underlying mechanisms of biochemistry, cell biology, cell development, and cell physiology. To streamline the understanding of such complex processes, researchers need the most current versions of genetic and physical maps, tools with the ability to recognize novel phenotypes or classify known phenotypes, and an intimate knowledge of the biochemical processes generating physiological and phenotypic effects. They must also know how all of these factors change and differ among species, diverse alleles, germplasms, and environmental conditions. While there are robust databases, such as MaizeGDB, for some of these types of raw data, other crucial components are missing. Moreover, the management of visually observed mutant phenotypes is still in its infant stage, let alone the complex query methods that can draw upon high-level and aggregated information to answer the questions of geneticists. In this paper, we address the scientific challenge and propose to develop a robust framework for managing the knowledge of visually observed phenotypes, mining the correlation of visual characteristics with genetic maps, and discovering the knowledge relating to cross-species conservation of visual and genetic patterns. The ultimate goal of this research is to allow a geneticist to submit phenotypic and genomic information on a mutant to a knowledge base and ask, "What genes or environmental factors cause this visually observed phenotype?".

scholarly journals Methionine Diet Evoked Hyperhomocysteinemia Causes Hippocampal Alterations, Metabolomics Plasma Changes and Behavioral Pattern in Wild Type Rats

2021 ◽  
Vol 22 (9) ◽  
pp. 4961
Author(s):  
Maria Kovalska ◽  
Eva Baranovicova ◽  
Dagmar Kalenska ◽  
Anna Tomascova ◽  
Marian Adamkov ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Brain Area ◽  
Critical Role ◽  
Cerebrovascular Diseases ◽  
Behavioral Pattern ◽  
Cell Physiology ◽  
Male Wistar Rats ◽  
High Level ◽  
Hippocampal Alterations ◽  
The Impact

L-methionine, an essential amino acid, plays a critical role in cell physiology. High intake and/or dysregulation in methionine (Met) metabolism results in accumulation of its intermediate(s) or breakdown products in plasma, including homocysteine (Hcy). High level of Hcy in plasma, hyperhomocysteinemia (hHcy), is considered to be an independent risk factor for cerebrovascular diseases, stroke and dementias. To evoke a mild hHcy in adult male Wistar rats we used an enriched Met diet at a dose of 2 g/kg of animal weight/day in duration of 4 weeks. The study contributes to the exploration of the impact of Met enriched diet inducing mild hHcy on nervous tissue by detecting the histo-morphological, metabolomic and behavioural alterations. We found an altered plasma metabolomic profile, modified spatial and learning memory acquisition as well as remarkable histo-morphological changes such as a decrease in neurons’ vitality, alterations in the morphology of neurons in the selective vulnerable hippocampal CA 1 area of animals treated with Met enriched diet. Results of these approaches suggest that the mild hHcy alters plasma metabolome and behavioural and histo-morphological patterns in rats, likely due to the potential Met induced changes in “methylation index” of hippocampal brain area, which eventually aggravates the noxious effect of high methionine intake.

scholarly journals Carl Singer (1945-2013) – Life on a Plate: Yeast genetics meetings and micromanipulators

2021 ◽  
Author(s):  
Harry Singer ◽  
Terrance G Cooper
Keyword(s):  
Molecular Biology ◽  
Cell Biology ◽  
Cutting Edge ◽  
Genetic Maps ◽  
Yeast Genetics

Abstract Micromanipulators, more than any other instrument, opened the early doors to developing the powerful genetics of yeast that underlies much of the molecular work today. The ability to separate the spores of a tetrad and analyze their phenotypes generated the genetic maps and biology upon which subsequent cloning, sequencing, cutting edge molecular and cell biology depended. This work describes the development of those micromanipulators from garage to barn to factory and the developer of the sophisticated instruments we use today. For more than 30 years Carl Singer and his family were staunch and generous supporters of the International Conferences on Yeast Genetics and Molecular Biology meetings both in Europe and America. Carl Singer's displays at meetings became a traditional fixture and engaged the appetites of many students and advanced researchers to employ a technique that many perceived as too complicated or difficult, but which he made simple and easy to learn. His experiences also document a sketch of the international yeast meetings, their venues and how they developed through the years.

Metabolic adjustments of small passerine birds for migration and cold

1983 ◽  
Vol 245 (6) ◽  
pp. R755-R767 ◽  
Author(s):  
W. R. Dawson ◽  
R. L. Marsh ◽  
M. E. Yacoe
Keyword(s):  
Passerine Birds ◽  
Complex Processes ◽  
Formative Stage ◽  
Group Breeding ◽  
Flight Muscles ◽  
Winter Cold ◽  
Metabolic Properties ◽  
Power Outputs ◽  
High Level ◽  
Order Passeriformes

Passerines (members of the order Passeriformes such as finches, chickadees, jays, and warblers) are predominantly small birds characterized by relatively intense metabolic rates. Members of this group breeding at middle or high latitudes may either evade winter cold by migration or enhance their resistance to it by acclimatization. We review the energetic consequences associated with these two modes of response. Despite their apparent dissimilarity, migration and winter acclimatization both depend on substantial aerobic endurance, and both involve extensive power outputs by the flight muscles in locomotion or shivering. Such power outputs entail extensive deposition and catabolism of fat. Information available on these processes and their control in passerine birds is discussed. Knowledge of them is still in a formative stage, but it is already clear that aerobic capacity of passerines is stable at a high level throughout the year. However, changes are observed in the activity of certain enzymes involved in the catabolism of fats and carbohydrates. Full interpretation of these findings must await additional research. Nevertheless it is evident that the complex processes of migration and winter acclimatization are intimately linked with the metabolic properties of the highly aerobic skeletal muscle contained within the flight apparatus of passerines.

scholarly journals A cellular endolysosome-modulating pore-forming protein from a toad is negatively regulated by its paralog under oxidizing conditions

2020 ◽  
Vol 295 (30) ◽  
pp. 10293-10306 ◽  
Author(s):  
Qiquan Wang ◽  
Xianling Bian ◽  
Lin Zeng ◽  
Fei Pan ◽  
Lingzhen Liu ◽  
...  
Keyword(s):  
Disulfide Bond ◽  
Cell Biology ◽  
Biochemical Properties ◽  
Bacterial Toxin ◽  
Cell Physiology ◽  
Dependent Manner ◽  
Membrane Pore ◽  
Intracellular Vesicles

Endolysosomes are key players in cell physiology, including molecular exchange, immunity, and environmental adaptation. They are the molecular targets of some pore-forming aerolysin-like proteins (ALPs) that are widely distributed in animals and plants and are functionally related to bacterial toxin aerolysins. βγ-CAT is a complex of an ALP (BmALP1) and a trefoil factor (BmTFF3) in the firebelly toad (Bombina maxima). It is the first example of a secreted endogenous pore-forming protein that modulates the biochemical properties of endolysosomes by inducing pore formation in these intracellular vesicles. Here, using a large array of biochemical and cell biology methods, we report the identification of BmALP3, a paralog of BmALP1 that lacks membrane pore-forming capacity. We noted that both BmALP3 and BmALP1 contain a conserved cysteine in their C-terminal regions. BmALP3 was readily oxidized to a disulfide bond-linked homodimer, and this homodimer then oxidized BmALP1 via disulfide bond exchange, resulting in the dissociation of βγ-CAT subunits and the elimination of biological activity. Consistent with its behavior in vitro, BmALP3 sensed environmental oxygen tension in vivo, leading to modulation of βγ-CAT activity. Interestingly, we found that this C-terminal cysteine site is well conserved in numerous vertebrate ALPs. These findings uncover the existence of a regulatory ALP (BmALP3) that modulates the activity of an active ALP (BmALP1) in a redox-dependent manner, a property that differs from those of bacterial toxin aerolysins.

scholarly journals Biological cell-based screening for scientific membranal and cytoplasmatic markers using dielectric spectroscopy

2008 ◽  
Vol 2 (2) ◽  
pp. 111-121
Author(s):  
Ragini Raj Singh ◽  
◽  
Amit Ron ◽  
Nick Fishelson ◽  
Irena Shur ◽  
...  
Keyword(s):  
Cell Lines ◽  
Dielectric Spectroscopy ◽  
Cell Biology ◽  
Screening Tool ◽  
Excitation Frequency ◽  
Cell Physiology ◽  
Biological Cell ◽  
Non Invasive ◽  
Native Cell ◽  
Biology Research

Dielectric spectroscopy (DS) of living biological cells is based on the analysis of cells suspended in a physiological medium. It provides knowledge of the polarization-relaxation response of the cells to external electric field as function of the excitation frequency. This response is strongly affected by both structural and molecular properties of the cells and, therefore, can reveal rare insights into cell physiology and behaviour. This study demonstrates the mapping potential of DS after cytoplasmic and membranal markers for cell-based screening analysis. The effect of membrane permittivity and cytoplasm conductivity was examined using tagged MBA and MDCK cell lines respectively. The comparison of the dielectric spectra of tagged and native cell lines reveals clear differences between the cells. In addition, the differences in the matching dielectric properties of the cells were discovered. Those findings support the high distinction resolution and sensitivity of DS after fine molecular and cellular changes, and hence, highlight the high potential of DS as non invasive screening tool in cell biology research.

E-government and transformation of service delivery in developing countries

2016 ◽  
Vol 10 (3) ◽  
pp. 368-390 ◽  
Author(s):  
Noore Alam Siddiquee
Keyword(s):  
Developing Countries ◽  
Service Delivery ◽  
Lessons Learned ◽  
Political Support ◽  
Primary Data ◽  
Content Type ◽  
Secondary Sources ◽  
Intimate Knowledge ◽  
Secondary Information ◽  
High Level

Purpose Since 2009, e-government has been high on governmental agenda in Bangladesh. Seen as a vehicle for improving governance and service delivery, it is also presented as a key to fighting poverty and achieving the millennium development goals. Thus, the goals of e-government remain broad and ambitious. Can a developing country such as Bangladesh realize its e-government vision? The purpose of this paper is to explore this and other related questions seeking to draw lessons that the Bangladesh experience may offer. Design/methodology/approach The paper draws primarily on secondary information, complemented by primary data gathered from various sources. In addition to an extensive review of secondary sources, necessary information was derived from websites of relevant government departments/agencies and through interviews and conversations with selected government officials having intimate knowledge on e-government projects at the field and local levels. Findings The paper demonstrates the ways in which various e-initiatives have transformed traditional administrative systems and practices, notwithstanding the nation’s limited overall e-development. It also shows how e-innovations have helped tackle some complex challenges, thereby adding to convenience and benefits to service users. A major conclusion of the paper is that although e-government is yet to make a breakthrough in governance and service delivery, it has set the wheels of change in motion. Practical implications E-government must be seen as a long term project, it must attract high-level political support and it requires fruitful collaboration between the public, private and non-governmental actors. Originality/value This paper adds to the limited knowledge in the field. Lessons learned from the Bangladesh experience have much relevance to other developing countries with similar socioeconomic circumstances. The policymakers and practitioners are expected to benefit from the insights of the paper.

A Cdc2 dependent checkpoint maintains diploidy in Drosophila

Development ◽  
1996 ◽  
Vol 122 (4) ◽  
pp. 1051-1058 ◽  
Author(s):  
S. Hayashi
Keyword(s):  
Central Nervous System ◽  
Dna Replication ◽  
Polytene Chromosomes ◽  
S Phase ◽  
Regulatory Subunit ◽  
Checkpoint Control ◽  
The Central Nervous System ◽  
Mutant Phenotypes ◽  
High Level ◽  
Diploid Cells

DNA replication in G2 does not normally occur due to the checkpoint control. To elucidate its mechanism, the functions of the escargot and Dmcdc2 genes of Drosophila were studied. When escargot function was eliminated, diploid imaginal cells that were arrested in G2 lost Cyclin A, a regulatory subunit of G2/M cdk, and entered an endocycle. escargot genetically interacted with Dmcdc2 which encodes a catalytic subunit of G2/M cdk. The mutant phenotypes of Dmcdc2 itself was similar to those of escargot: many diploid cells in imaginal discs, salivary glands and the central nervous system entered an endocycle and sometimes formed polytene chromosomes. Since mitotically quiescent abdominal histoblasts still required Dmcdc2 to remain diploid, the inhibitory activity of G2/M cdk on DNA replication appeared to be separable from its activity as the mitosis promoting factor. These results suggest that in G2, escargot is required to maintain a high level of G2/M cdk that actively inhibits the entry into S phase.

Access Control Models for Online Social Networks

2014 ◽  
pp. 451-484
Author(s):  
Rula Sayaf ◽  
Dave Clarke
Keyword(s):  
Social Networks ◽  
Access Control ◽  
Online Social Networks ◽  
Personal Data ◽  
Security And Privacy ◽  
Open Problems ◽  
Access Control Models ◽  
Control Models ◽  
Underlying Mechanisms ◽  
High Level

Access control is one of the crucial aspects in information systems security. Authorizing access to resources is a fundamental process to limit potential privacy violations and protect users. The nature of personal data in online social networks (OSNs) requires a high-level of security and privacy protection. Recently, OSN-specific access control models (ACMs) have been proposed to address the particular structure, functionality and the underlying privacy issues of OSNs. In this survey chapter, the essential aspects of access control and review the fundamental classical ACMs are introduced. The specific OSNs features and review the main categories of OSN-specific ACMs are highlighted. Within each category, the most prominent ACMs and their underlying mechanisms that contribute enhancing privacy of OSNs are surveyed. Toward the end, more advanced issues of access control in OSNs are discussed. Throughout the discussion, different models and highlight open problems are contrasted. Based on these problems, the chapter is concluded by proposing requirements for future ACMs.

scholarly journals J. Murdoch Mitchison. 11 June 1922—17 March 2011

2019 ◽  
Vol 67 ◽  
pp. 279-306
Author(s):  
Peter Fantes ◽  
Sally Mitchison
Keyword(s):  
Cell Biology ◽  
Sea Urchins ◽  
Growth Cycle ◽  
Cell Physiology ◽  
Time Work ◽  
University Of Edinburgh ◽  
Membrane Changes ◽  
Post War ◽  
The University ◽  
Zoology Department

John Murdoch Mitchison, known as Murdoch, was elected FRS in recognition of his work on the cell cycle. This emerged from a lifelong interest in the natural sciences, interrupted by war-time work in Operational Research which developed his critical appraisal of research technique. Post-war, he completed a PhD at Cambridge, then worked with Sir Michael Swann FRS (1962) on mitotic membrane changes in sea urchins. In 1953 Murdoch joined the University of Edinburgh Zoology Department and in time switched his interest to the fission yeast Schizosaccharomyces pombe . Over the next 30 years he investigated cell growth and division, employing a meticulous approach to experiments. He considered there to be a ‘growth cycle’ in cells, independent of the DNA-division cycle. There is experimental evidence to support this idea, but further investigations of it have been limited. Actively fostering a relaxed but industrious and enquiring ethos in the lab, Murdoch ran the department jointly with Aubrey Manning. The Mitchison group's work at Edinburgh attracted students including Paul Nurse (later Sir Paul Nurse; FRS 1989, PRS 2010–2015), Béla Novak, Kim Nasmyth (FRS 1989) and Peter Fantes as well as many visiting academics. Murdoch's work on S. pombe came to both national and international recognition, forming a foundation for the current thriving community of researchers in cell physiology, cell genetics and molecular biology. Murdoch is remembered for his single-minded commitment to cell biology research and his generous, fair-minded support of younger colleagues and students. He was, additionally, an expert landscape gardener, a convivial host and phenomenally well-informed on most subjects.

Invited Review: Engineering approaches to cytoskeletal mechanics

2000 ◽  
Vol 89 (5) ◽  
pp. 2085-2090 ◽  
Author(s):  
Dimitrije Stamenović ◽  
Ning Wang
Keyword(s):  
Cell Biology ◽  
Theoretical Models ◽  
Force Balance ◽  
Mechanical Forces ◽  
Cellular Functions ◽  
Cellular Mechanics ◽  
Recent Developments ◽  
Biochemical Mechanisms ◽  
Underlying Mechanisms ◽  
Biochemical Signals

An outstanding problem in cell biology is how cells sense mechanical forces and how those forces affect cellular functions. Various biophysical and biochemical mechanisms have been invoked to answer this question. A growing body of evidence indicates that the deformable cytoskeleton (CSK), an intracellular network of interconnected filamentous biopolymers, provides a physical basis for transducing mechanical signals into biochemical signals. Therefore, to understand how mechanical forces regulate cellular functions, it is important to know how cells respond to changes in the CSK force balance and to identify the underlying mechanisms that control transmission of mechanical forces throughout the CSK and bring it to equilibrium. Recent developments of new experimental techniques for measuring cell mechanical properties and novel theoretical models of cellular mechanics make it now possible to identify and quantitate the contributions of various CSK structures to the overall balance of mechanical forces in the cell. This review focuses on engineering approaches that have been used in the past two decades in studies of the mechanics of the CSK.

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