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Mousa, M.

Publications and source records attributed to Mousa, M..

6 recordsLinked to original sources

BfBio: a graph-based tool for the prediction of Angiogenic Stalk Cell genes using a Personalized PageRank algorithm

Although most human protein coding genes have functional annotations in databases, such as GeneCards, many remain poorly characterized. To address this gap, computational tools can be leveraged to predict the functional roles of under-annotated genes by extracting patterns from complex biological networks. Here we introduce Brain-for-Biotech (BfBio), a framework designed to identify genes important for vascular endothelial cells (EC), which are crucial cells for vessel formation (angiogenesis), vascular homeostasis, hemostasis and blood/tissue barrier function but also critical mediators of immunity and cancer progression. BfBio utilizes a Personalized PageRank (PPR) algorithm on an integrated network of different omics datasets and publicly available gene-gene/protein-protein interaction databases. In this study, we apply the predictive capabilities of BfBio to infer angiogenic stalk cell phenotype function in genes for which this function was not known before. By leveraging a set of genes characterizing the stalk cell cluster in lung tumor EC models previously identified, we have achieved a high Area Under Receiver Operative Characteristic (AUC-ROC) performance (0.837). Enrichment analysis, coupled with a text mining application, further confirmed that among the 49 predicted genes four of them were poorly characterized yet possessed biologically relevant properties and were linked to cancer, thereby validating BfBio as a robust tool for prioritizing novel therapeutic targets in vascular biology.

cancer biology↗

Trained Immunity Affecting Dendritic Cell Differentiation and Function in Rheumatoid Arthritis

Rheumatoid arthritis affects [~]0.5-1% of the adult population and results in joint inflammation, chronic pain, and many systemic comorbidities. Immune and inflammatory tissue damage is the main pathogenic mechanism in rheumatoid arthritis, and involves the hyperactivation of both innate and adaptive immune systems. Trained immunity has become well established as an important feature of the innate immune system that allows the host to mount functionally altered immune responses based on their previous history of immune exposures, independently of the classical adaptive immunological memory. However, the role of trained immunity in systemic autoimmune and inflammatory disorders remains poorly understood. In the current work, we demonstrate that emergency myelopoiesis is induced in chronic rheumatoid arthritis in murine models and acts not only to enhance innate immune cell numbers but also to produce functionally altered innate immune cells. Such effects are cell-intrinsic to hematopoietic stem and progenitor cells (HSPCs) and persist independently of the inflammatory disease milieu. Importantly, these trained immunity mechanisms impact not only macrophages but also dendritic cells, which are the major antigen presenting cells that bridge the innate and adaptive immune responses. Trained dendritic cells show changes in global gene expression profiles, and significantly altered responses to recall immune stimulation and capacity for T cell activation. This study therefore represents the first demonstration of dendritic cell trained immunity in rheumatoid arthritis.

immunology↗

Site-1 Protease is a negative regulator of sarcolipin promoter activity

The timed contraction and relaxation of myofibers in tissues such as the heart and skeletal muscle occurs via the tightly regulated movement of calcium ions into and out of the sarcoplasmic reticulum (SR). In skeletal muscle, this phenomenon enables humans to exercise, perform day-to-day tasks, and to breathe. Sarcolipin, a small regulatory protein, prevents calcium ions from entering the SR by binding to and inhibiting SERCA, contributing to myofiber contraction. Disruptions in sarcolipin expression are implicated in the pathophysiology of obesity and musculoskeletal disease. However, the mechanisms regulating sarcolipin expression are not clearly understood. We recently showed that Site-1 Protease (S1P) is a regulator of skeletal muscle function and mass. Here, we report that deleting S1P in mouse skeletal muscle increases sarcolipin expression, without impacting calcium SR flux. In cultured cells, S1P negatively regulates sarcolipin by activating the transcription factor ATF6, which inhibits basal- and calcineurin-stimulated sarcolipin promoter activity. We identified a cAMP response element binding protein (CREB) binding site on the sarcolipin promoter that is necessary for promoter activation, and show that in muscle, CREB binds to the sarcolipin promoter and that this binding is enhanced when S1P is deleted. These discoveries expand our knowledge of S1P biology and the mechanisms controlling calcium regulatory genes.

molecular biology↗

An Emirati pangenome incorporating a diploid telomere-to-telomere reference

Reference data on genomic variation form the basis of genetic research. Limitations in identifying genetic variation from single reference sequences have been recently overcome, as improvements in sequencing technologies have allowed the generation of pangenomic references from multiple accurate, chromosome-level de novo assemblies. Here, we present a comprehensive Emirati telomere-to-telomere (T2T) pangenome generated from 58 individuals, comprising 28 trio-based and 30 single-sample assemblies. The resulting 116 haplotype-resolved assemblies demonstrate high contiguity, with a median continuity of 150 Mb and a median quality value (QV) of 59, achieving T2T-level scaffold status for 71.9% of chromosomes. These assemblies form the foundation of the Emirati T2T pangenome graph. The graph reveals levels of genomic diversity comparable to those reported by the Human Pangenome Reference Consortium, while also capturing regionally enriched and difficult-to-assemble variation, uniquely accessible through the Emirati T2T assemblies. This reference makes a valuable global contribution to human pangenomics and serves as a critical resource for advancing precision medicine in the United Arab Emirates.

genomics↗

Deciphering Salt Stress Responses in Solanum pimpinellifolium through High-Throughput Phenotyping.

Soil salinity is a major environmental stressor affecting agricultural productivity worldwide. Understanding plant responses to salt stress is crucial for developing resilient crop varieties. Wild relatives of cultivated crops, such as wild tomato, Solanum pimpinellifolium, can serve as a useful resource to further expand the resilience potential of the cultivated germplasm, S. lycopersicum. In this study, we employed high-throughput phenotyping in the greenhouse and field conditions to explore salt stress responses of a S. pimpinellifolium diversity panel. Our study revealed extensive phenotypic variations in response to salt stress, with traits such as transpiration rate, shoot mass, and ion accumulation showing significant correlations with plant performance. We found that while transpiration was a key determinant of plant performance in the greenhouse, shoot mass strongly correlated with yield under field conditions. Conversely, ion accumulation was the least influential factor under greenhouse conditions. Through a Genome Wide Association Study, we identified candidate genes not previously associated with salt stress, highlighting the power of high-throughput phenotyping in uncovering novel aspects of plant stress responses. This study contributes to our understanding of salt stress tolerance in S. pimpinellifolium and lays the groundwork for further investigations into the genetic basis of these traits, ultimately informing breeding efforts for salinity tolerance in tomato and other crops.

plant biology↗

Dynamic changes in the mouse hepatic lipidome following warm ischemia reperfusion injury

Liver failure secondary to nonalcoholic fatty liver disease (NAFLD) has become the most common cause for liver transplantation in many parts of the world. Moreover, the prevalence of NAFLD not only increases the demand for liver transplantation, but also limits the supply of suitable donor organs because steatosis predisposes grafts to ischemia-reperfusion injury (IRI). There are currently no pharmacological interventions to limit hepatic IR injury because the mechanisms by which steatosis leads to increased injury are unclear. To identify potential novel mediators of IR injury, we used liquid chromatography and mass spectrometry to assess temporal changes in the hepatic lipidome in steatotic and non-steatotic livers after warm IRI in mice. Our untargeted analyses revealed distinct differences between the steatotic and non-steatotic response to IRI and highlighted dynamic changes in lipid composition with marked changes in glycerolipids and glycerophospholipids. These findings enhance our knowledge of the lipidomic changes that occur following IRI and provide a foundation for future mechanistic studies. A better understanding of the mechanisms underlying such changes will lead to novel therapeutic strategies to combat IR injury.

biochemistry↗