Speciation and changes in male gene expression in Drosophila

Genome ◽  
2020 ◽  
pp. 1-11
Author(s):  
Bahar Patlar ◽  
Alberto Civetta

It has long been acknowledged that changes in the regulation of gene expression may account for major organismal differences. However, we still do not fully understand how changes in gene expression evolve and how do such changes influence organisms’ differences. We are even less aware of the impact such changes might have in restricting gene flow between species. Here, we focus on studies of gene expression and speciation in the Drosophila model. We review studies that have identified gene interactions in post-mating reproductive isolation and speciation, particularly those that modulate male gene expression. We also address studies that have experimentally manipulated changes in gene expression to test their effect in post-mating reproductive isolation. We highlight the need for a more in-depth analysis of the role of selection causing disrupted gene expression of such candidate genes in sterile/inviable hybrids. Moreover, we discuss the relevance to incorporate more routinely assays that simultaneously evaluate the potential effects of environmental factors and genetic background in modulating plastic responses in male genes and their potential role in speciation.

Blood ◽  
2019 ◽  
Vol 134 (24) ◽  
pp. 2195-2208 ◽  
Author(s):  
Daniel Sasca ◽  
Haiyang Yun ◽  
George Giotopoulos ◽  
Jakub Szybinski ◽  
Theo Evan ◽  
...  

Cohesin mutations are common in myeloid malignancy. Sasca et al elucidate the potential role of cohesin loss in myelodysplastic syndrome and acute myeloid leukemia (MDS/AML). They demonstrate that cohesin binding is critical for erythroid-specific gene expression and that reduction in cohesin impairs terminal erythroid maturation and promotes myeloid malignancy.


2021 ◽  
Author(s):  
Robert Mukiibi ◽  
Carolina Peñaloza ◽  
Alejandro Gutierrez ◽  
José M. Yáñez ◽  
Ross D. Houston ◽  
...  

Salmon rickettsial septicaemia (SRS), caused by the intracellular bacteria Piscirickettsia Salmonis, generates significant mortalities to farmed Atlantic salmon, particularly in Chile. Due to its economic importance, a wealth of research has focussed on the biological mechanisms underlying pathogenicity of P. salmonis, the host response, and genetic variation in host resistance. DNA methylation is a fundamental epigenetic mechanism that influences almost every biological process via the regulation of gene expression and plays a key role in the response of an organism to stimuli. In the current study, the role of head kidney and liver DNA methylation in the response to P. salmonis infection was investigated in a commercial Atlantic salmon population. A total of 66 salmon were profiled using reduced representation bisulphite sequencing (RRBS), with head kidney and liver methylomes compared between infected animals (3 and 9 days post infection) and uninfected controls. These included groups of salmon with divergent (high or low) breeding values for resistance to P. salmonis infection, to examine the influence of genetic resistance. Head kidney and liver showed organ-specific global methylation patterns, but with similar distribution of methylation across gene features. Integration of methylation with RNA-Seq data revealed that methylation levels predominantly showed a negative correlation with gene expression, although positive correlations were also observed. Methylation within the first exon showed the strongest negative correlation with gene expression. A total of 911 and 813 differentially methylated CpG sites were identified between infected and control samples in the head kidney at 3 and 9 days respectively, whereas only 30 and 44 sites were differentially methylated in the liver. Differential methylation in the head kidney was associated with immunological processes such as actin cytoskeleton regulation, phagocytosis, endocytosis and pathogen associated pattern receptor signaling. We also identified 113 and 48 differentially methylated sites between resistant and susceptible fish in the head kidney and liver respectively. Our results contribute to the growing understanding of the role of methylation in regulation of gene expression and response to infectious diseases, and in particular reveal key immunological functions regulated by methylation in Atlantic salmon in response to P. salmonis.


2018 ◽  
Vol 19 (12) ◽  
pp. 3820 ◽  
Author(s):  
Matteo Spinelli ◽  
Salvatore Fusco ◽  
Claudio Grassi

Diet is the main environmental stimulus chronically impinging on the organism throughout the entire life. Nutrients impact cells via a plethora of mechanisms including the regulation of both protein post-translational modifications and gene expression. Palmitoylation is the most-studied protein lipidation, which consists of the attachment of a molecule of palmitic acid to residues of proteins. S-palmitoylation is a reversible cysteine modification finely regulated by palmitoyl-transferases and acyl-thioesterases that is involved in the regulation of protein trafficking and activity. Recently, several studies have demonstrated that diet-dependent molecules such as insulin and fatty acids may affect protein palmitoylation. Here, we examine the role of protein palmitoylation on the regulation of gene expression focusing on the impact of this modification on the activity of chromatin remodeler enzymes, transcription factors, and nuclear proteins. We also discuss how this physiological phenomenon may represent a pivotal mechanism underlying the impact of diet and nutrient-dependent signals on human diseases.


Biosystems ◽  
2021 ◽  
Vol 203 ◽  
pp. 104368 ◽  
Author(s):  
Julie D. Thompson ◽  
Raymond Ripp ◽  
Claudine Mayer ◽  
Olivier Poch ◽  
Christian J. Michel

2020 ◽  
Author(s):  
Julie D. Thompson ◽  
Raymond Ripp ◽  
Claudine Mayer ◽  
Olivier Poch ◽  
Christian J. Michel

AbstractThe X circular code is a set of 20 trinucleotides (codons) that has been identified in the protein-coding genes of most organisms (bacteria, archaea, eukaryotes, plasmids, viruses). It has been shown previously that the X circular code has the important mathematical property of being an error-correcting code. Thus, motifs of the X circular code, i.e. a series of codons belonging to X, which are significantly enriched in the genes, allow identification and maintenance of the reading frame in genes. X motifs have also been identified in many transfer RNA (tRNA) genes and in important functional regions of the ribosomal RNA (rRNA), notably in the peptidyl transferase center and the decoding center. Here, we investigate the potential role of X motifs as functional elements in the regulation of gene expression. Surprisingly, the definition of a simple parameter identifies several relations between the X circular code and gene expression. First, we identify a correlation between the 20 codons of the X circular code and the optimal codons/dicodons that have been shown to influence translation efficiency. Using previously published experimental data, we then demonstrate that the presence of X motifs in genes can be used to predict the level of gene expression. Based on these observations, we propose the hypothesis that the X motifs represent a new genetic signal, contributing to the maintenance of the correct reading frame and the optimization and regulation of gene expression.Author SummaryThe standard genetic code is used by (quasi-) all organisms to translate information in genes into proteins. Recently, other codes have been identified in genomes that increase the versatility of gene decoding. Here, we focus on the circular codes, an important class of genome codes, that have the ability to detect and maintain the reading frame during translation. Motifs of the X circular code are enriched in protein-coding genes from most organisms from bacteria to eukaryotes, as well as in important molecules in the gene translation machinery, including transfer RNA (tRNA) and ribosomal RNA (rRNA). Based on these observations, it has been proposed that the X circular code represents an ancestor of the standard genetic code, that was used in primordial systems to simultaneously decode a smaller set of amino acids and synchronize the reading frame. Using previously published experimental data, we highlight several links between the presence of X motifs in genes and more efficient gene expression, supporting the hypothesis that the X circular code still contributes to the complex dynamics of gene regulation in extant genomes.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Anna S. E. Cuomo ◽  
Giordano Alvari ◽  
Christina B. Azodi ◽  
Davis J. McCarthy ◽  
Marc Jan Bonder ◽  
...  

Abstract Background Single-cell RNA sequencing (scRNA-seq) has enabled the unbiased, high-throughput quantification of gene expression specific to cell types and states. With the cost of scRNA-seq decreasing and techniques for sample multiplexing improving, population-scale scRNA-seq, and thus single-cell expression quantitative trait locus (sc-eQTL) mapping, is increasingly feasible. Mapping of sc-eQTL provides additional resolution to study the regulatory role of common genetic variants on gene expression across a plethora of cell types and states and promises to improve our understanding of genetic regulation across tissues in both health and disease. Results While previously established methods for bulk eQTL mapping can, in principle, be applied to sc-eQTL mapping, there are a number of open questions about how best to process scRNA-seq data and adapt bulk methods to optimize sc-eQTL mapping. Here, we evaluate the role of different normalization and aggregation strategies, covariate adjustment techniques, and multiple testing correction methods to establish best practice guidelines. We use both real and simulated datasets across single-cell technologies to systematically assess the impact of these different statistical approaches. Conclusion We provide recommendations for future single-cell eQTL studies that can yield up to twice as many eQTL discoveries as default approaches ported from bulk studies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Anastasia Ricci ◽  
Sara Orazi ◽  
Federica Biancucci ◽  
Mauro Magnani ◽  
Michele Menotta

AbstractAtaxia telangiectasia (AT) is a rare genetic neurodegenerative disease. To date, there is no available cure for the illness, but the use of glucocorticoids has been shown to alleviate the neurological symptoms associated with AT. While studying the effects of dexamethasone (dex) in AT fibroblasts, by chance we observed that the nucleoplasmic Lamin A/C was affected by the drug. In addition to the structural roles of A-type lamins, Lamin A/C has been shown to play a role in the regulation of gene expression and cell cycle progression, and alterations in the LMNA gene is cause of human diseases called laminopathies. Dex was found to improve the nucleoplasmic accumulation of soluble Lamin A/C and was capable of managing the large chromatin Lamin A/C scaffolds contained complex, thus regulating epigenetics in treated cells. In addition, dex modified the interactions of Lamin A/C with its direct partners lamin associated polypeptide (LAP) 2a, Retinoblastoma 1 (pRB) and E2F Transcription Factor 1 (E2F1), regulating local gene expression dependent on E2F1. These effects were differentially observed in both AT and wild type (WT) cells. To our knowledge, this is the first reported evidence of the role of dex in Lamin A/C dynamics in AT cells, and may represent a new area of research regarding the effects of glucocorticoids on AT. Moreover, future investigations could also be extended to healthy subjects or to other pathologies such as laminopathies since glucocorticoids may have other important effects in these contexts as well.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Godfrey Grech ◽  
Marieke von Lindern

Organisation of RNAs into functional subgroups that are translated in response to extrinsic and intrinsic factors underlines a relatively unexplored gene expression modulation that drives cell fate in the same manner as regulation of the transcriptome by transcription factors. Recent studies on the molecular mechanisms of inflammatory responses and haematological disorders indicate clearly that the regulation of mRNA translation at the level of translation initiation, mRNA stability, and protein isoform synthesis is implicated in the tight regulation of gene expression. This paper outlines how these posttranscriptional control mechanisms, including control at the level of translation initiation factors and the role of RNA binding proteins, affect hematopoiesis. The clinical relevance of these mechanisms in haematological disorders indicates clearly the potential therapeutic implications and the need of molecular tools that allow measurement at the level of translational control. Although the importance of miRNAs in translation control is well recognised and studied extensively, this paper will exclude detailed account of this level of control.


2022 ◽  
Vol 12 (5) ◽  
pp. 971-977
Author(s):  
Ruoyu Zhu ◽  
Zhonglin Wang

This study investigated the impact of microRNA (miR)-376b derived from BMSCs on glioma progression. BMSCs were transfected with miR-376b mimic, miR-376b inhibitor or NC and then cocultured with glioma cells followed by measuring cell behaviors by MTT assay, Transwell assay and flow cytometry, FOXP2 and miR-376b expression by Western blot and RT-qPCR. After confirming the inhibitory and mimicking activity of transfection, we found that overexpression of miR-376b in BMSCs decreased glioma cell invasion, migration and proliferation but promoted cell apoptosis within 24 h and 48 h after transfection along with reduced number of cells in S-phase. Mechanically, miR-376b targeted miR-376b and up-regulation of miR-376b caused down-regulation of FOXP2 (p < 0.05). Overexpression of miR-376b in BMSCs decelerated glioma cell cycle and inhibitedmalignant behaviors of glioma cells by targeting FOXP2 expression. These evidence unveils the potential role of FOXP2 as a biomarker for the treatment of gliomas.


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