Search results for "Biogenesis"

miRNAs Regulation and Its Role as Biomarkers in Endometriosis.

2016

MicroRNAs (miRNAs) are small non-coding RNAs (18-22 nt) that function as modulators of gene expression. Since their discovery in 1993 in C. elegans, our knowledge about their biogenesis, function, and mechanism of action has increased enormously, especially in recent years, with the development of deep-sequencing technologies. New biogenesis pathways and sources of miRNAs are changing our concept about these molecules. The study of the miRNA contribution to pathological states is a field of great interest in research. Different groups have reported the implication of miRNAs in pathologies such as cancer, diabetes, cardiovascular, and gynecological diseases. It is also well-known that miRNAs…

Testing the Domino Theory of Gene Loss in Buchnera aphidicola: The Relevance of Epistatic Interactions

2018

The domino theory of gene loss states that when some particular gene loses its function and cripples a cellular function, selection will relax in all functionally related genes, which may allow for the non-functionalization and loss of these genes. Here we study the role of epistasis in determining the pattern of gene losses in a set of genes participating in cell envelope biogenesis in the endosymbiotic bacteria Buchnera aphidicola. We provide statistical evidence indicating pairs of genes in B. aphidicola showing correlated gene loss tend to have orthologs in Escherichia coli known to have alleviating epistasis. In contrast, pairs of genes in B. aphidicola not showing correlated gene loss…

Microbiota-Mitochondria Inter-Talk: A Potential Therapeutic Strategy in Obesity and Type 2 Diabetes

2020

The rising prevalence of obesity and type 2 diabetes (T2D) is a growing concern worldwide. New discoveries in the field of metagenomics and clinical research have revealed that the gut microbiota plays a key role in these metabolic disorders. The mechanisms regulating microbiota composition are multifactorial and include resistance to stress, presence of pathogens, diet, cultural habits and general health conditions. Recent evidence has shed light on the influence of microbiota quality and diversity on mitochondrial functions. Of note, the gut microbiota has been shown to regulate crucial transcription factors, coactivators, as well as enzymes implicated in mitochondrial biogenesis and meta…

Prefoldin-like Bud27 influences the transcription of ribosomal components and ribosome biogenesis in Saccharomyces cerevisiae

2020

Understanding the functional connection that occurs for the three nuclear RNA polymerases to synthesize ribosome components during the ribosome biogenesis process has been the focal point of extensive research. To preserve correct homeostasis on the production of ribosomal components, cells might require the existence of proteins that target a common subunit of these RNA polymerases to impact their respective activities. This work describes how the yeast prefoldin-like Bud27 protein, which physically interacts with the Rpb5 common subunit of the three RNA polymerases, is able to modulate the transcription mediated by the RNA polymerase I, likely by influencing transcription elongation, the …

Crystals and the debates on the nature, recognition and origin of life

2020

Progressive axonopathy when oligodendrocytes lack the myelin protein CMTM5

2021

AbstractOligodendrocytes facilitate rapid impulse propagation along the axons they myelinate and support their long-term integrity. However, the functional relevance of many myelin proteins has remained unknown. Here we find that expression of the tetraspan-transmembrane protein CMTM5 (Chemokine-like factor-like MARVEL-transmembrane domain containing protein 5) is highly enriched in oligodendrocytes and CNS myelin. Genetic disruption of the Cmtm5-gene in oligodendrocytes of mice does not impair the development or ultrastructure of CNS myelin. However, oligodendroglial Cmtm5-deficiency causes an early-onset progressive axonopathy, which we also observe in global and in tamoxifen-induced olig…

Echovirus 1 infection depends on biogenesis of novel multivesicular bodies

2011

Summary Non-enveloped picornavirus echovirus 1 (EV1) clusters its receptor α2β1 integrin and causes their internalization and accumulation in α2β1 integrin enriched multivesicular bodies (α2-MVBs). Our results here show that these α2-MVBs are distinct from acidic late endosomes/lysosomes by several criteria: (i) live intra-endosomal pH measurements show that α2-MVBs are not acidic, (ii) they are not positive for the late endosomal marker LBPA or Dil-LDL internalized to lysosomes, and (iii) simultaneous stimulation of epidermal growth factor receptor (EGFR) and α2β1 integrin clustering leads to their accumulation in separate endosomes. EGFR showed downregulation between 15 min and 2 h, where…

2019

Abstract Background Physical activity and dietary intake of dairy products are associated with improved metabolic health. Dairy products are rich with branched chain amino acids that are essential for energy production. To gain insight into the mechanisms underlying the benefit of the sub-chronic effects of running and intake of milk protein supplements, we studied L ow C apacity R unner rats (LCR), a rodent exercise model with risk for metabolic disorders. We especially focused on the role of Sirtuins, energy level dependent proteins that affect many cellular metabolic processes. Methods Forty-seven adult LCR female rats sedentary or running voluntarily in wheels were fed normal chow and g…

Prebiotic Evolution and the Origin of Life: Chemical and Biochemical Aspects

1988

Evolution, as the term is used here, signifies any development or change adapting to the environment. Chemical evolution connotes changes of chemical substances, it thus signifies that changes occur fundamentally in the molecules. Frequently “chemical evolution” is used synonymously for “abiotic” or “prebiotic formation” of organic molecules in a cosmic system, usually on the prebiotic (or primitive) Earth. It is then assumed that the organic molecules were formed from the constituents of the primitive atmosphere, hydrosphere, and — in part — lithospere.

Origin of Life, Theories Of

2017

Modern advances in biology, geology, chemistry, and astronomy have allowed us to elaborate models and hypotheses on the origin of life on Earth within the framework of the evolutionary theory. About four billion years ago, a rich inventory of organic compounds accumulated on the planet, as a product of volcanic, atmospheric, and cosmic chemistry. As chemical systems became increasingly more complex, a critical point was reached with the appearance of self-replicative polymers. This marks the possibility of optimizing abiotic systems by natural selection and historical contingency, which were added to the determinism of abiotic chemistry. A landmark of the origin of life was the articulation…