Ligand Binding Study of Human PEBP1/RKIP: Interaction with Nucleotides and Raf-1 Peptides Evidenced by NMR and Mass Spectrometry

Background Human Phosphatidylethanolamine binding protein 1 (hPEBP1) also known as Raf kinase inhibitory protein (RKIP), affects various cellular processes, and is implicated in metastasis formation and Alzheimer's disease. Human PEBP1 has also been shown to inhibit the Raf/MEK/ERK pathway. Numerous reports concern various mammalian PEBP1 binding ligands. However, since PEBP1 proteins from many different species were investigated, drawing general conclusions regarding human PEBP1 binding properties is rather difficult. Moreover, the binding site of Raf-1 on hPEBP1 is still unknown. Methods/Findings In the present study, we investigated human PEBP1 by NMR to determine the binding site of four different ligands: GTP, FMN, and one Raf-1 peptide in tri-phosphorylated and non-phosphorylated forms. The study was carried out by NMR in near physiological conditions, allowing for the identification of the binding site and the determination of the affinity constants KD for different ligands. Native mass spectrometry was used as an alternative method for measuring KD values. Conclusions/Significance Our study demonstrates and/or confirms the binding of hPEBP1 to the four studied ligands. All of them bind to the same region centered on the conserved ligand-binding pocket of hPEBP1. Although the affinities for GTP and FMN decrease as pH, salt concentration and temperature increase from pH 6.5/NaCl 0 mM/20°C to pH 7.5/NaCl 100 mM/30°C, both ligands clearly do bind under conditions similar to what is found in cells regarding pH, salt concentration and temperature. In addition, our work confirms that residues in the vicinity of the pocket rather than those within the pocket seem to be required for interaction with Raf-1.METASU

Studying protein–protein affinity and immobilized ligand–protein affinity interactions using MS-based methods

This review discusses the most important current methods employing mass spectrometry (MS) analysis for the study of protein affinity interactions. The methods are discussed in depth with particular reference to MS-based approaches for analyzing protein–protein and protein–immobilized ligand interactions, analyzed either directly or indirectly. First, we introduce MS methods for the study of intact protein complexes in the gas phase. Next, pull-down methods for affinity-based analysis of protein–protein and protein–immobilized ligand interactions are discussed. Presently, this field of research is often called interactomics or interaction proteomics. A slightly different approach that will be discussed, chemical proteomics, allows one to analyze selectivity profiles of ligands for multiple drug targets and off-targets. Additionally, of particular interest is the use of surface plasmon resonance technologies coupled with MS for the study of protein interactions. The review addresses the principle of each of the methods with a focus on recent developments and the applicability to lead compound generation in drug discovery as well as the elucidation of protein interactions involved in cellular processes. The review focuses on the analysis of bioaffinity interactions of proteins with other proteins and with ligands, where the proteins are considered as the bioactives analyzed by MS

Probing the drug interactome by chemical proteomics

Approved PDE5 inhibitors for the treatment of erectile dysfunction (ED) include sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis), all of which are considered very specific and ‘safe’ drugs. However, even highly selective, FDA approved drugs can have the potential to bind to other unintended targets, possibly leading to side effects. Some reported side effects observed during ED treatment include headache, flushing and transient visual problems. Understanding the molecular causes of such side effects is an important part of the drug development process and can help in the understanding of the mechanisms of drug action. In the research described in this thesis, the interactome of several, closely related, PDE5 inhibitors was characterized to obtain further insight in their ability to bind proteins other than PDE5. The pull-down affinity experiments were optimized to decrease binding of non-specific proteins. The optimized pull-down assay was then combined with high resolution quantitative proteomics to get a clear and unbiased insight into the protein interactors of PDE5 inhibitors. Several new specific interacting proteins were identified and verified and it was shown that slight modifications of the inhibitors can alter their specificity to favor these new protein targets. Throughout the work described in this thesis it has become evident that chemical proteomics can be an effective approach to describe the interactome of drugs but that it can also be used to identify potential new targets of known compounds, opening up the possibility to identify new potential therapeutic uses for known and approved drugs

Reasons for seeking a divorce in Iran

Given the increasing rate of divorce in Iran, together with the need to adopt preventive measures based on cultural conditions, a requirement of utmost importance is to explore the reasons that drive Iranian couples to seek a divorce. In this nationwide study, which was conducted in nine capital cities chosen from 31 provinces in Iran, a total of 3,200 men and women (1,600 couples), who had petitioned the court for a divorce, received individual expert counseling services through a reliable and valid questionnaire. Of the 17 reasons that the divorce seekers provided as explanation for their decision, three were prominent: the inability to resolve conflicts, which led to disputes, dissatisfaction with the manner by which their spouses expressed their love and emotions, and discontent regarding a spouse�s personality traits. The findings highlighted the necessity of planning for enhanced conflict resolution and communication among men and women in Iranian society. © The Author(s) 2020

Marital satisfaction and emotional divorce among Iranian married individuals: A survey of hospital visitors of nine provinces

BACKGROUND: Evidence is accumulating that the pattern and nature of marital relationships are very different in different cultures. This nationwide study aimed to determine marital satisfaction and the prevalence of emotional divorce as well as to identify the sociodemographic correlates in a Muslim population. MATERIALS AND METHODS: In this cross-sectional study, one-third of Iran's provinces were selected randomly and a representative sample of inhabitants of their central city was included in the study. The ENRICH marital satisfaction scale was used to determine marital satisfaction levels. A single-item measure with confirmed validity and reliability was used to find out about emotional divorce. The demographic variables included respondent's age, spouse's age, gender, educational level, residency, childbearing, and premarriage familiarity. RESULTS: Of the 2033 participants, 1034 were women (50.9). Nearly one-third of both men and women had academic degrees. Almost 53 of them were satisfied with their marital life and 9.7 had emotional divorce. Men with academic degrees had a higher probability of marital satisfaction (odds ratio OR =1.26, 95% confidence interval CI: 1.04-1.53) and a lower prevalence of emotional divorce (OR = 0.37, 95% CI: 0.24-0.58). CONCLUSION: This study showed a relatively high percentage of marital dissatisfaction as well as emotional divorce. Policymakers should strengthen premarriage education programs and postmarriage counseling centers. © 2020 Journal of Education and Health Promotion | Published by Wolters Kluwer - Medknow

Bootstrapping technique + embeddings = emotional corpus an- notated automatically.

Detecting depression or personality traits, tutoring and student behaviour systems, or identifying cases of cyber-bulling are a few of the wide range of the applications, in which the automatic detection of emotion is crucial. This task can contribute to the benefit of business, society, politics or education. The main objective of our research is focused on the improvement of the supervised emotion detection systems developed so far, through the definition and implementation of a technique to annotate large scale English emotional corpora automatically and with high standards of reliability. Our proposal is based on a bootstrapping process made up two main steps: the creation of the seed using NRC Emotion Lexicon and its extension employing the distributional semantic similarity through words embeddings. The results obtained are promising and allow us to confirm the soundness of the bootstrapping technique combined with the word embedding to label emotional corpora automatically