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Nuage (cell Biology)
Nuage are ''Drosophila melanogaster'' germline granules. Nuage are the hallmark of ''Drosophila melanogaster'' germline cells, which have an electron-dense perinuclear structure and can silence the selfish genetic elements in ''Drosophila melanogaster''. The term 'Nuage' comes from the French word for 'cloud', as they appear as nebulous electron-dense bodies by electron microscopy. They are found in nurse cells of the developing ''Drosophila melanogaster'' egg chamber and are composed of various types of proteins, including RNA-helicases, Tudor domain proteins, Piwi-clade Argonaute proteins, in addition to a PRMT5 methylosome composed of Capsuléen and its co-factor, Valois ( MEP50). See piRNA Pirna (; hsb, Pěrno; ) is a town in Saxony, Germany and capital of the administrative district Sächsische Schweiz-Osterzgebirge. The town's population is over 37,000. Pirna is located near Dresden and is an important district town as well as ... for more information. Reference ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Melanogaster
''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly" or "pomace fly". Starting with Charles W. Woodworth's 1901 proposal of the use of this species as a model organism, ''D. melanogaster'' continues to be widely used for biological research in genetics, physiology, microbial pathogenesis, and life history evolution. As of 2017, five Nobel Prizes have been awarded to drosophilists for their work using the insect. ''D. melanogaster'' is typically used in research owing to its rapid life cycle, relatively simple genetics with only four pairs of chromosomes, and large number of offspring per generation. It was originally an African species, with all non-African lineages having a common origin. Its geographic range includes all continents, including islands. ''D. melanogaster'' is a common pest in homes, restaurants, and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granule (cell Biology)
In cell biology, a granule is a small particle. It can be any structure barely visible by light microscopy. The term is most often used to describe a secretory vesicle. In leukocytes A group of leukocytes, called granulocytes, contain granules and play an important role in the immune system. The granules of certain cells, such as natural killer cells, contain components which can lead to the lysis of neighboring cells. The granules of leukocytes are classified as azurophilic granules or specific granules. Leukocyte granules are released in response to immunological stimuli during a process known as degranulation. In platelets The granules of platelets are classified as dense granules and alpha granules. α-Granules are unique to platelets and are the most abundant of the platelet granules, numbering 50–80 per platelet 2. These granules measure 200–500 nm in diameter and account for about 10% of platelet volume. They contain mainly proteins, both membrane-associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perinuclear Space
The nuclear envelope, also known as the nuclear membrane, is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which encloses the genetic material. The nuclear envelope consists of two lipid bilayer membranes: an inner nuclear membrane and an outer nuclear membrane. The space between the membranes is called the perinuclear space. It is usually about 10–50 nm wide. The outer nuclear membrane is continuous with the endoplasmic reticulum membrane. The nuclear envelope has many nuclear pores that allow materials to move between the cytosol and the nucleus. Intermediate filament proteins called lamins form a structure called the nuclear lamina on the inner aspect of the inner nuclear membrane and give structural support to the nucleus. Structure The nuclear envelope is made up of two lipid bilayer membranes, an inner nuclear membrane and an outer nuclear membrane. These membranes are connected to each other by nuclear pores. Two sets of in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selfish Gene Theory
With gene defined as "not just one single physical bit of DNA [but] all replicas of a particular bit of DNA distributed throughout the world", the gene-centered view of evolution, gene's eye view, gene selection theory, or selfish gene theory holds that adaptive evolution occurs through the differential survival of competing genes, increasing the allele frequency of those alleles whose phenotypic trait effects successfully promote their own propagation. The proponents of this viewpoint argue that, since heritability, heritable information is passed from generation to generation almost exclusively by DNA, natural selection and evolution are best considered from the perspective of genes. Proponents of the gene-centered viewpoint argue that it permits understanding of diverse phenomena such as altruism in animals, altruism and intragenomic conflict that are otherwise difficult to explain from an organism-centered viewpoint. The gene-centered view of evolution is a synthesis of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nurse Cell
In general biology or reproductive physiology the term nurse cell is defined as a cell which provides food, helps other cells and provides stability to their neighboring cells. The term nurse cell is used in several unrelated ways in different scientific fields. Human physiology Nurse cells are specialized macrophages residing in the bone marrow that assist in the development of red blood cells. They absorb the nuclei of immature red blood cells and may provide growth factors to help the red blood cells mature. In the bone marrow, immature red blood cells (erythroblasts) can be seen grouped in a cluster around a nurse cell. The epithelial cell found in the cortex of the thymus is also called a "nurse cell." These cells produce Thymic hormones that cause T lymphocytes to mature and differentiate. Parasitology In parasitology, a nurse cell is an infected cell in the disease trichinosis discovered by Dickson Despommier. A trichinella larva enters a cell and develops there, probably a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Helicase
Helicases are a class of enzymes thought to be vital to all organisms. Their main function is to unpack an organism's genetic material. Helicases are motor proteins that move directionally along a nucleic acid phosphodiester backbone, separating two hybridized nucleic acid strands (hence '' helic- + -ase''), using energy from ATP hydrolysis. There are many helicases, representing the great variety of processes in which strand separation must be catalyzed. Approximately 1% of eukaryotic genes code for helicases. The human genome codes for 95 non-redundant helicases: 64 RNA helicases and 31 DNA helicases. Many cellular processes, such as DNA replication, transcription, translation, recombination, DNA repair, and ribosome biogenesis involve the separation of nucleic acid strands that necessitates the use of helicases. Some specialized helicases are also involved in sensing of viral nucleic acids during infection and fulfill a immunological function. Function Helicases are oft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tudor Domain
In molecular biology, a Tudor domain is a conserved protein structural domain originally identified in the Tudor protein encoded in Drosophila. The Tudor gene was found in a Drosophila screen for maternal factors that regulate embryonic development or fertility. Mutations here are lethal for offspring, inspiring the name Tudor, as a reference to the Tudor King Henry VIII and the several miscarriages experienced by his wives. Structure A Tudor domain is a protein region approximately 60 amino acids in length, which folds into an SH3-like structure with a five-stranded antiparallel beta-barrel form. Tudor domains can further be organized into functional units consisting of either a single Tudor domain, tandem Tudor domains, or hybrid Tudor domains consisting of two Tudor domains linked by an anti-parallel beta-sheet made from their shared second and third beta-strands. An essential component of the Tudor domain structure is the aromatic-binding cage formed by several (typically 4– ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piwi
Piwi (or PIWI) genes were identified as gene regulation, regulatory proteins responsible for stem cell and germ cell cell differentiation, differentiation. Piwi is an abbreviation of P element, P-element Induced WImpy testis in ''Drosophila melanogaster, Drosophila''. Piwi proteins are highly conservation (genetics), conserved RNA-binding proteins and are present in both plants and animals. Piwi proteins belong to the Argonaute/Piwi family and have been classified as nuclear proteins. Studies on ''Drosophila'' have also indicated that Piwi proteins have no slicer activity conferred by the presence of the Piwi domain. In addition, Piwi associates with heterochromatin protein 1, an epigenetic modifier, and piRNA-complementary sequences. These are indications of the role Piwi plays in epigenetic regulation. Piwi proteins are also thought to control the biogenesis of piRNA as many Piwi-like proteins contain slicer activity which would allow Piwi proteins to process precursor piRNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argonaute
The Argonaute protein family, first discovered for its evolutionarily conserved stem cell function, plays a central role in RNA silencing processes as essential components of the RNA-induced silencing complex (RISC). RISC is responsible for the gene silencing phenomenon known as RNA interference (RNAi). Argonaute proteins bind different classes of small non-coding RNAs, including microRNAs (miRNAs), small interfering RNAs (siRNAs) and Piwi-interacting RNAs (piRNAs). Small RNAs guide Argonaute proteins to their specific targets through sequence complementarity (base pairing), which then leads to mRNA cleavage, translation inhibition, and/or the initiation of mRNA decay. The name of this protein family is derived from a mutant phenotype resulting from mutation of AGO1 in '' Arabidopsis thaliana'', which was likened by Bohmert et al. to the appearance of the pelagic octopus '' Argonauta argo''. RNA interference RNA interference (RNAi) is a biological process in which the RNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PRMT5
Protein arginine N-methyltransferase 5 is an enzyme that in humans is encoded by the ''PRMT5'' gene. PRMT5 symmetrically dimethylates H2AR3, H4R3, H3R2, and H3R8 in vivo, all of which are linked to a range of transcriptional regulatory events. PRMT5 is a highly conserved arginine methyltransferase that translocated from the cytoplasm to the nucleus at embryonic day ~E8.5, and during preimplantation development at the ~4-cell stage. Model organisms Model organisms have been used in the study of PRMT5 function. A conditional knockout mouse line, called ''Prmt5tm2a(EUCOMM)Wtsi'' was generated as part of the International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists. Male and female animals underwent a standardized phenotypic screen to determine the effects of deletion. Twenty five tests were carried out on mutant mice and two significant abnormalities were observed. No homozy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WD Repeat-containing Protein 77
Methylosome protein 50 is a protein that in humans is encoded by the ''WDR77'' gene. Interactions WD repeat-containing protein 77 has been shown to Protein-protein interaction, interact with CTDP1 and Protein arginine methyltransferase 5. References Further reading * * * * * * * * * * * * * * * * External links * {{gene-1-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PiRNA
Pirna (; hsb, Pěrno; ) is a town in Saxony, Germany and capital of the administrative district Sächsische Schweiz-Osterzgebirge. The town's population is over 37,000. Pirna is located near Dresden and is an important district town as well as a ''Große Kreisstadt''. Geography Geographical location Pirna is located in the vicinity of the Sandstone Mountains in the upper Elbe valley, where two nearby tributaries, Wesenitz from the north and Gottleuba from the south, flow into the Elbe. It is also called the "gate to the Saxon Switzerland" ( Ger: ''Tor zur Sächsischen Schweiz''). The Saxon wine region ( Ger: ''Sächsische Weinstraße''), which was established in 1992, stretches from Pirna via Pillnitz, Dresden, and Meissen to Diesbar-Seußlitz. Neighboring municipalities Pirna is located southeast of Dresden. Neighboring municipalities are Bad Gottleuba-Berggießhübel (town), Bahretal, Dohma, Dohna (town), Dürrröhrsdorf-Dittersbach, Heidenau (town), Königstei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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