Eukaryotic Signature Proteins

Abstract:

Eukaryotic Signature Proteins (ESPs) are proteins that delineate the eukaryotes from the archaea and bacteria. They have no recognisable homologues in any prokaryotic genome, but their homologues are present in all main branches of eukaryotes. ESPs are thus likely to have descended from ancient proteins that have existed since the first eukaryotic cell. The last dataset of ESPs was calculated more than a decade ago, thus with advances in technology and the rapid completion of many evolutionary important genomes, this dataset required recalculating. This study recalculated the Giardia lamblia ESP dataset and provides a procedure to calculate signature proteins beginning with any species. The G. lamblia ESP dataset contained a range of proteins including many associated with the membrane, cytoskeleton, nucleus and protein synthesis. ESP datasets have implications on current models of eukaryotic evolution, having high importance in phylogenetic analysis due to ESPs’ consistency and conservation in all eukaryotic species.

Prevalence and Factors Associated with Disclosure of HIV Diagnosis to Infected Children Receiving Antiretroviral Treatment in Public Health Care Facilities in Gauteng, South Africa

Abstract:

HIV infected children who started antiretroviral therapy (ART) in public health facilities in South Africa have survived to older age and disclosure has become an essential part of their care. Available data on HIV disclosure to children were collected much earlier in the provision of ART in South Africa. The aim of the study was to (a) determine the characteristics of caregivers of pediatric HIV patients in Gauteng, South Africa, (b) estimate the prevalence and timing of HIV disclosure among these patients, and (c) assess the factors associated with disclosure status. A cross-sectional study was conducted among 286 caregivers of paediatric ART children aged 4–17 in two centres in Gauteng, South Africa. Bivariate and multivariate logistic regression analyses were carried out. The highest proportion of care givers were biological mothers (n=140, 49.3%). The mean age of the children was 8.5 years, (range 4-17 years). More than a third (n=99, 34%) were disclosed their HIV status, and the mean age at disclosure was 9.3 years, (SD = 2.7). Child’s age older than 10 years (OR =1.63; 95% CI: 1.44–1.85), having a nonbiological caregiver (OR=1.75; 95% CI: 1.06-2.89), caregiver educational level (OR =0.64; 95% CI: 0.47–0.87), and caregiver’s age older than 60 years (OR=1.02; 95% CI: 1.01-1.04), were significantly associated with HIV disclosure to infected children. The relatively higher prevalence of disclosure is attributed to increasing access to paediatric ART. Training healthcare providers to support caregivers in disclosure will increase the rate of disclosure to HIV infected children receiving ART in public health facilities.

Editorial for Journal of Proteomics and Genomics Research

Abstract:

Optimization and ZSPORE Analysis of Affinity Purification Coupled with Tandem Mass Spectrometry in Mammalian Cells

Abstract:

Defining protein-protein interactions is essential for understanding the mechanisms by which cells regulate basic functions, such as metabolism, transcription, and signal transduction. Affinity purification followed by tandem mass spectrometry (AP-MS) has application for discovery of new interactors regulating various cellular processes. Here we optimize the purification method for AP-MS and develop a simplified unbiased analytical tool, Z-score plus prey occurrence and reproducibility (ZSPORE) for data analysis. Using this pipeline we achieve a higher efficiency of AP-MS and enhanced identification of high confidence interacting proteins (HCIP) in mammalian cells. When applied to analysis of the innate immune interactome, these methods enhanced HCIP identification. In addition, we investigated the GRB2 complex, which is associated with signal transduction and cell growth. Twenty-four known GRB2 interacting proteins were identified plus 26 new GRB2 binding partners. Thus, these straightforward methods recapitulate known protein interactions, discover novel complexes, and allow mapping of protein interaction networks.

Substrate Stiffness Influences the Time Dependence of CTGF Protein Expression in Müller Cells

Abstract:

Following ocular trauma and retinal detachment, gliotic changes in the retina may develop over the subsequent month, a process known as PVR (proliferative vitreoretinopathy). There have been no successful therapeutic interventions to inhibit PVR. The protein CTGF (Connective Tissue Growth Factor) has been associated with retinal PVR and other fibrotic diseases of the retina in clinical studies but the mechanistic link between different pathologies and retinal gliosis has not been determined. In addition, CTGF has been previously noted to be associated, in some cases, with YAP/TAZ (Yes-associated protein and Tafazzin protein complex), transcriptional regulatory proteins that change subcellular localization in response to mechanical cues, such as the stiffness of the underlying material. We have previously shown that the mRNA for CTGF is markedly (100-fold) upregulated in retinal Müller cells grown on soft substrates.

In order to evaluate if the mechanism by which mechanotransduction modulating CTGF production in retinal Müller cells involves the YAP/TAZ complex, this study tests the influence of substrate stiffness on the time dependence of CTGF protein expression, as well as subcellular localization of YAP/TAZ using a conditionally-immortalized mouse retinal Müller cell line plated on laminin-coated, polyacrylamide substrates of varying elastic modulus. Changes were assayed using immunohistochemistry and ELISA (Enzyme-Linked ImmunoSorbent Assay).

In retinal Müller cells, the relationship between elastic modulus and the pattern of CTGF protein expression was bimodal, with CTGF levels rising more rapidly for cells on hard substrates and more slowly for cells grown on soft substrates. In addition, nuclear localization of YAP/TAZ corresponded directly to the maximum CTGF expression.

Volvulus of the Small Bowel Due to Malrotation During Pregnancy: A Case-Report

Abstract:

Volvulus occurring during pregnancy is a rare complication, still potentially lethal nowadays for both the mother and child due to several, early arising complications. We report here a case of small bowel volvulus in a 28 weeks and 4 days, 29 years-old, pregnant woman with a past medical history of appendectomy in her childhood. Patient presented in emergency department with abdominal pain and abnormal hepatic tests. Cholangio-MRI suggested bowel obstruction due to volvulus that was confirmed by gastroscopy (showing the obstruction) and intestinal MRI. Patient was first treated by laparoscopy but, due to a very complicated abdominal status with the presence of several adhesions of the small bowel, surgery was changed to an open laparotomy, which allowed discovery and repositioning of small bowel malrotation and removal of adhesions. Both patient and the foetus were healthy after surgery and the patient was then discharged. In the light of this particularly rare case of small bowel volvulus due to malrotion, we will describe the pathology of bowel obstruction and more particularly volvulus during pregnancy and discuss its diagnosis and treatment.

The NH2-Terminal Ig Domains of Insect Projectin could serve as Elastic Elements

Abstract:

The connecting C-filaments of insect indirect flight muscles have been proposed as one of the elements providing muscle elasticity for the asynchronous muscle physiology of derived insects. Two large modular proteins, kettin/Sallimus and projectin make up these filaments, and for both proteins the N-terminal sequences span the extensible I-band and are proposed as the elastic segments. The C-filaments have not been studied in insects, such as dragonflies, crickets, and Lepidoptera with muscles which are largely synchronous in physiology and display different levels of muscle stiffness. In this paper we focus our efforts on the projectin protein of several insects with synchronous flight muscles; namely dragonfly, cricket, and moth. We provide evidence for the localization of projectin over the sarcomere I-Z-I region that is consistent with the existence of C-filaments in synchronous flight muscles. Additionally, we determine the sequences for the NH2-terminal region of projectin in these insects and describe the presence of alternative splice variants. Using predictors of intrinsically disordered regions, we identify possible unfolded segments, especially around the short linker sequences found between the NH2 Ig domains. We propose a possible picture of projectin NH2-terminal region organized as different segments contributing elastic responses to stretch by either unfolding of highly disordered sequences (PEVK) or reorientation of domains by bending or twisting of disordered linkers between the Ig domains.

Evolutionary Conservation of Hox Genes in Vertebrate Brain Development

Abstract:

Hox genes, their conserved derivatives, and the pathways responsible for their expression have been extensively studied in the fruit fly, Drosophila melanogaster;the experimentation done in the Drosophila model system has given developmental biologists tools to better understand the role and significance of Hox genes and their derivatives in anterior-posterior axis determination in the Drosophila embryo. Along with this, Drosophila research opened up the door to investigation on the conservation of Hox genes between vertebrates and invertebrates. Comparative embryology in mice, chickens, pufferfish, and zebrafish have shown conserved Hox gene expression patterns specifically along the anterior-posterior axis. Recently, comparative analysis performed on dorsal-ventral axis formation showed that patterning and segmentation of the spinal cord is influenced by the action of Hox genes as well. This review will briefly consider the evolution of the vertebrate brain and the evolution and conservation of Hox genes in regulating hindbrain patterning and spinal cord development.

Efficacy of Ricinus communis L., Cassia occidentalis L. and Bacillus thuringiensis against Helicoverpa armigera Hübner (Lepidoptera: Noctuidae)

Abstract:

Helicoverpaarmigera is one of the most destructive pests of field crops worldwide. The Study was designed to investigate through laboratory screening the insecticidal activity of Ricinus communis, Cassia occidentalis and Bacillus thuringiensis var. Kurstaki (Btk) and their combinations against 2^nd larval instar of H. armigera. Five concentrations (4%, 6%, 8%, 10% and 12%) of each plant extract and (0.62, 1.25, 2.5, 5, and 10 mg/ml) of Bt were used in this experiment. Mortality (%) was recorded after 24,48,72 and 96 hrs post treatment. The results showed that R. communis, C. occidentalis and Btkhave insecticidal activity against 2^nd instar larvae of H. armigera. The highest concentration (12%) caused 80% and 70% larval mortality after 96 hrs for R. communis and C. occidental respectively.

The statistical analysis revealed that there is a significant differences between all treatments and control. Additionally, all combinations (plant/plant or plant/Bt) increased the mortality %. The results also clearly demonstrate that the R. communis are significantly more toxic than C. occidental where the LC₅₀ values were 6.4 % for R. communis and 8.1% for C. occidental. On the other hand LC₅₀ value for Bt was 0.41 mg/ml.

The binary mixture of R. communis and C. occidental have a potentiation effect after 48 hrs. Regarding the mixture of Bt and plant extracts the results revealed that R. communis and Bt mixture induced a potentiation effect whereas C. occidental and Bt mixture induced a an additive effects.

Nature Inspired Bargain Optimization Algorithm for Effective Interpretation of Geoelectrical Data

Abstract:

Geoelectrical resistivity data collected from the ground contain lot of noises and errors. It requires efficient algorithm to reduce the errors to make an actual inversion models. Though different algorithm can be applied, nature inspired algorithm is more potential in inverting geoelectrical data in an elegant and comprehensive way. Bargain Optimization (BO) algorithm is framed on the concept of bargaining things to purchase for needs. In general, effective bargaining results in more profit and leads to loss when it fails. In this research work, Bargain Optimization algorithm is applied to invert geoelectrical data and the effective bargaining will take time to process and to obtain the required model. The input data is AB/2, apparent resistivity data and the inverted model through BO algorithm is successfully matched with the available litholog section of the study area. The output graphs have profit/loss bar graph, which reveals the status of bargaining during a particular number of epochs.