scholarly journals Defining the subcellular distribution and metabolic channeling of phosphatidylinositol

2020 ◽  
Vol 219 (3) ◽  
Author(s):  
Joshua G. Pemberton ◽  
Yeun Ju Kim ◽  
Jana Humpolickova ◽  
Andrea Eisenreichova ◽  
Nivedita Sengupta ◽  
...  

Phosphatidylinositol (PI) is an essential structural component of eukaryotic membranes that also serves as the common precursor for polyphosphoinositide (PPIn) lipids. Despite the recognized importance of PPIn species for signal transduction and membrane homeostasis, there is still a limited understanding of the relationship between PI availability and the turnover of subcellular PPIn pools. To address these shortcomings, we established a molecular toolbox for investigations of PI distribution within intact cells by exploiting the properties of a bacterial enzyme, PI-specific PLC (PI-PLC). Using these tools, we find a minor presence of PI in membranes of the ER, as well as a general enrichment within the cytosolic leaflets of the Golgi complex, peroxisomes, and outer mitochondrial membrane, but only detect very low steady-state levels of PI within the plasma membrane (PM) and endosomes. Kinetic studies also demonstrate the requirement for sustained PI supply from the ER for the maintenance of monophosphorylated PPIn species within the PM, Golgi complex, and endosomal compartments.

2019 ◽  
Author(s):  
Joshua G. Pemberton ◽  
Yeun Ju Kim ◽  
Nivedita Sengupta ◽  
Andrea Eisenreichova ◽  
Daniel J. Toth ◽  
...  

AbstractPhosphatidylinositol (PtdIns) is an essential structural component of eukaryotic membranes that also serves as the common precursor for polyphosphoinositide (PPIn) lipids. Despite the recognized importance of PPIn species for signal transduction and membrane homeostasis, there is still a limited understanding of how the dynamic regulation of PtdIns synthesis and transport contributes to the turnover of PPIn pools. To address these shortcomings, we capitalized on the substrate selectivity of a bacterial enzyme, PtdIns-specific PLC, to establish a molecular toolbox for investigations of PtdIns distribution and availability within intact cells. In addition to its presence within the ER, our results reveal low steady-state levels of PtdIns within the plasma membrane (PM) and endosomes as well as a relative enrichment of PtdIns within the cytosolic leaflets of the Golgi complex, peroxisomes, and outer mitochondrial membranes. Kinetic studies also demonstrate the requirement for sustained PtdIns supply from the ER for the maintenance of monophosphorylated PPIn species within the PM, Golgi complex, and endosomal compartments.SummaryPemberton et al. characterize a molecular toolbox for the visualization and manipulation of phosphatidylinositol (PtdIns) within intact cells. Results using these approaches define the steady-state distribution of PtdIns across subcellular membrane compartments as well as provide new insights into the relationship between PtdIns availability and polyphosphoinositide turnover.


2020 ◽  
Vol 21 (8) ◽  
pp. 2905
Author(s):  
Maher A. Dayeh ◽  
George Livadiotis ◽  
Farzan Aminian ◽  
Kwan H. Cheng ◽  
James L. Roberts ◽  
...  

The association between plasma cholesterol levels and the development of dementia continues to be an important topic of discussion in the scientific community, while the results in the literature vary significantly. We study the effect of reducing oxidized neuronal cholesterol on the lipid raft structure of plasma membrane. The levels of plasma membrane cholesterol were reduced by treating the intact cells with methyl-ß-cyclodextrin (MßCD). The relationship between the cell viability with varying levels of MßCD was then examined. The viability curves are well described by a modified form of the empirical Gompertz law of mortality. A detailed statistical analysis is performed on the fitting results, showing that increasing MßCD concentration has a minor, rather than significant, effect on the cellular viability. In particular, the dependence of viability on MßCD concentration was found to be characterized by a ~25% increase per 1 μM of MßCD concentration.


1977 ◽  
Vol 164 (1) ◽  
pp. 139-145 ◽  
Author(s):  
Graham S. Byng ◽  
John M. Turner

1. During growth of Pseudomonas phenazinium on l-threonine medium, phenazine pigment formation commenced early and 1,6-dihydroxyphenazine 5,10-dioxide (iodinin) was the major component. Growth on l-[U-14C]threonine showed that when growth was complete about 25% of the label had been incorporated into phenazines and 30% into cell substance. 2. The addition of d-[2,3,4,5(n)-14C]shikimate to cultures at different phases of growth showed that the greatest efficiency of incorporation (about 70%) occurred in the mid- to late-exponential phase. Phenazines accounting for most of the 14C supplied were iodinin and 9-hydroxyphenazine-1-carboxylate plus 2,9-dihydroxyphenazine-1-carboxylate. Radioactivity incorporated into cell substance was about one-third of the amount found in phenazines. 3. Kinetic studies showed that radioactivity from a pulse of [14C]-shikimate was incorporated into phenazines immediately, without a discernible lag, and into all detectable phenazines simultaneously rather than sequentially. 4. Radioactive phenazines isolated from culture media were fed to growing cultures and their metabolism was studied. The results supported a scheme for the biosynthesis of iodinin and 1,8-dihydroxyphenazine 10-monoxide by a branched pathway. 5. It is proposed that phenazine-1,6-dicarboxylate is the common precursor of all naturally occurring phenazines.


EMPIRISMA ◽  
2017 ◽  
Vol 26 (1) ◽  
Author(s):  
Limas Dodi

According to Abdulaziz Sachedina, the main argument of religious pluralism in the Qur’an based on the relationship between private belief (personal) and public projection of Islam in society. By regarding to private faith, the Qur’an being noninterventionist (for example, all forms of human authority should not be disturb the inner beliefs of individuals). While the public projection of faith, the Qur’an attitude based on the principle of coexistence. There is the willingness of the dominant race provide the freedom for people of other faiths with their own rules. Rules could shape how to run their affairs and to live side by side with the Muslims. Thus, based on the principle that the people of Indonesia are Muslim majority, it should be a mirror of a societie’s recognizion, respects and execution of religious pluralism. Abdul Aziz Sachedina called for Muslims to rediscover the moral concerns of public Islam in peace. The call for peace seemed to indicate that the existence of increasingly weakened in the religious sense of the Muslims and hence need to be reaffi rmed. Sachedina also like to emphasize that the position of peace in Islam is parallel with a variety of other doctrines, such as: prayer, fasting, pilgrimage and so on. Sachedina also tried to show the argument that the common view among religious groups is only one religion and traditions of other false and worthless. “Antipluralist” argument comes amid the reality of human religious differences. Keywords: Theology, Pluralism, Abdulaziz Sachedina


2019 ◽  
Vol 26 (34) ◽  
pp. 6207-6221 ◽  
Author(s):  
Innocenzo Rainero ◽  
Alessandro Vacca ◽  
Flora Govone ◽  
Annalisa Gai ◽  
Lorenzo Pinessi ◽  
...  

Migraine is a common, chronic neurovascular disorder caused by a complex interaction between genetic and environmental risk factors. In the last two decades, molecular genetics of migraine have been intensively investigated. In a few cases, migraine is transmitted as a monogenic disorder, and the disease phenotype cosegregates with mutations in different genes like CACNA1A, ATP1A2, SCN1A, KCNK18, and NOTCH3. In the common forms of migraine, candidate genes as well as genome-wide association studies have shown that a large number of genetic variants may increase the risk of developing migraine. At present, few studies investigated the genotype-phenotype correlation in patients with migraine. The purpose of this review was to discuss recent studies investigating the relationship between different genetic variants and the clinical characteristics of migraine. Analysis of genotype-phenotype correlations in migraineurs is complicated by several confounding factors and, to date, only polymorphisms of the MTHFR gene have been shown to have an effect on migraine phenotype. Additional genomic studies and network analyses are needed to clarify the complex pathways underlying migraine and its clinical phenotypes.


Author(s):  
Justine Pila

This chapter considers the meaning of the terms that appropriately denote the subject matter protectable by registered trade mark and allied rights, including the common law action of passing off. Drawing on the earlier analyses of the objects protectable by patent and copyright, it defines the trade mark, designation of origin, and geographical indication in their current European and UK conception as hybrid inventions/works in the form of purpose-limited expressive objects. It also considers the relationship between the different requirements for trade mark and allied rights protection, and related principles of entitlement. In its conclusion, the legal understandings of trade mark and allied rights subject matter are presented as answers to the questions identified in Chapter 3 concerning the categories and essential properties of the subject matter in question, their method of individuation, and the relationship between and method of establishing their and their tokens’ existence.


2021 ◽  
Vol 5 (1) ◽  
pp. 43-51
Author(s):  
Jeong-A Jo

This study aims to examine the common features and differences in how the Chinese-character classifier ‘ ben 本’ is used in Chinese, Korean, and Japanese, and will explore the factors that have affected the categorization processes and patterns of the classifier ‘ ben 本.’ Consideration of the differences in the patterns of usage and categorization of the same Chinese classifier in different languages enables us to look into the perception of the world and the socio cultural differences inherent in each language, the differences in the perception of Chinese characters, and the relationship between classifiers.


Elenchos ◽  
2020 ◽  
Vol 41 (1) ◽  
pp. 181-194
Author(s):  
Angela Longo

AbstractThe following work features elements to ponder and an in-depth explanation taken on the Anca Vasiliu’s study about the possibilities and ways of thinking of God by a rational entity, such as the human being. This is an ever relevant topic that, however, takes place in relation to Platonic authors and texts, especially in Late Antiquity. The common thread is that the human being is a God’s creature who resembles him and who is image of. Nevertheless, this also applies within the Christian Trinity according to which, not without problems, the Son is the image of the Father. Lastly, also the relationship of the Spirit with the Father and the Son, always within the Trinity, can be considered as a relationship of similarity, but again not without critical issues between the similarity of attributes, on the one hand, and the identity of nature, on the other.


Religions ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 199
Author(s):  
Maria Ledstam

This article engages with how religion and economy relate to each other in faith-based businesses. It also elaborates on a recurrent idea in theological literature that reflections on different visions of time can advance theological analyses of the relationship between Christianity and capitalism. More specifically, this article brings results from an ethnographic study of two faith-based businesses into conversation with the ethicist Luke Bretherton’s presentation of different understandings of the relationship between Christianity and capitalism. Using Theodore Schatzki’s theory of timespace, the article examines how time and space are constituted in two small faith-based businesses that are part of the two networks Business as Mission (evangelical) and Economy of Communion (catholic) and how the different timespaces affect the religious-economic configurations in the two cases and with what moral implications. The overall findings suggest that the timespace in the Catholic business was characterized by struggling caused by a tension between certain ideals on how religion and economy should relate to each other on the one hand and how the practice evolved on the other hand. Furthermore, the timespace in the evangelical business was characterized by confidence, caused by the business having a rather distinct and achievable goal when it came to how they wanted to be different and how religion should relate to economy. There are, however, nuances and important resemblances between the cases that cannot be explained by the businesses’ confessional and theological affiliations. Rather, there seems to be something about the phenomenon of tension-filled and confident faith-based businesses that causes a drive in the practices towards the common good. After mapping the results of the empirical study, I discuss some contributions that I argue this study brings to Bretherton’s presentation of the relationship between Christianity and capitalism.


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