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Nucleocytoplasmic Large DNA Viruses
''Nucleocytoviricota'' is a phylum of viruses. Members of the phylum are also known as the nucleocytoplasmic large DNA viruses (NCLDV), which serves as the basis of the name of the phylum with the suffix - for virus phylum. These viruses are referred to as nucleocytoplasmic because they are often able to replicate in both the host's cell nucleus and cytoplasm. The phylum is notable for containing the giant viruses. There are nine families of NCLDVs that all share certain genomic and structural characteristics; however, it is uncertain whether the similarities of the different families of this group have a common viral ancestor. One feature of this group is a large genome and the presence of many genes involved in DNA repair, DNA replication, transcription, and translation. Typically, viruses with smaller genomes do not contain genes for these processes. Most of the viruses in this family also replicate in both the host's nucleus and cytoplasm, thus the name nucleocytoplasmic. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living Cell (biology), cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 16,000 of the millions of List of virus species, virus species have been described in detail. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent viral particles, or ''virions'', consisting of (i) genetic material, i.e., long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factor
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription (genetics), transcription of genetics, genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The function of TFs is to regulate—turn on and off—genes in order to make sure that they are Gene expression, expressed in the desired Cell (biology), cells at the right time and in the right amount throughout the life of the cell and the organism. Groups of TFs function in a coordinated fashion to direct cell division, cell growth, and cell death throughout life; cell migration and organization (body plan) during embryonic development; and intermittently in response to signals from outside the cell, such as a hormone. There are approximately 1600 TFs in the human genome. Transcription factors are members of the proteome as well as regulome. TFs work alone or with other proteins in a complex, by promoting (a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double-strand Break Repair Model
A double-strand break repair model refers to the various models of pathways that cells undertake to repair double-strand breaks (DSB). DSB repair is an important cellular process, as the accumulation of unrepaired DSB could lead to chromosomal rearrangements, tumorigenesis or even cell death. In human cells, there are two main DSB repair mechanisms: Homologous recombination (HR) and non-homologous end joining (NHEJ). HR can be seen as a more accurate site specific form of repair. It requires much more larger and intricate protein complexes. These complexes that involve proteins such as RAD51 (searches for homology and mediates strand invasion) and BRCA2 (the well studied RAD51 localizer) are critical in support of DNA replication and the recovery of stalled or broken replication forks. NHEJ modifies and ligates the damaged ends regardless of homology. In terms of DSB repair pathway choice, most mammalian cells appear to favor NHEJ rather than HR. This is because the employment of H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homologous Recombination
Homologous recombination is a type of genetic recombination in which genetic information is exchanged between two similar or identical molecules of double-stranded or single-stranded nucleic acids (usually DNA as in Cell (biology), cellular organisms but may be also RNA in viruses). Homologous recombination is widely used by cells to accurately DNA repair, repair harmful DNA breaks that occur on both strands of DNA, known as double-strand breaks (DSB), in a process called homologous recombinational repair (HRR). Homologous recombination also produces new combinations of DNA sequences during meiosis, the process by which eukaryotes make gamete cells, like sperm and ovum, egg cells in animals. These new combinations of DNA represent genetic variation in offspring, which in turn enables populations to Adaptation, adapt during the course of evolution. Homologous recombination is also used in horizontal gene transfer to exchange genetic material between different strains and species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ranavirus
''Ranavirus'' is a genus of viruses in the family ''Iridoviridae''. There are six other genus, genera of viruses within the family ''Iridoviridae'', but ''Ranavirus'' is the only one that includes viruses that are infectious to amphibians and reptiles. Additionally, it is one of the three genera within this family which infect teleostei, teleost fishes, along with ''Lymphocystivirus'' and ''Megalocytivirus''. Ecological impact The Ranaviruses, like the Megalocytiviruses, are an emerging infectious disease, emerging group of closely related DNA, dsDNA viruses which cause systemic disease, systemic infections in a wide variety of wild and cultured fresh and saltwater fishes. As with Megalocytiviruses, ''Ranavirus'' outbreaks are therefore of considerable economic importance in aquaculture, as epizootics can result in moderate fish loss or mass mortality events of cultured fishes. Unlike Megalocytiviruses, however, ''Ranavirus'' infections in amphibians have been implicated as a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andrias Davidianus
The Chinese giant salamander (''Andrias davidianus'') is one of the largest salamanders and one of the largest amphibians in the world.''Andrias davidianus'' -Amphibiaweb It is fully aquatic, and is to rocky mountain streams and lakes in the river basin of central . It has also been introduced to < ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridoviridae
''Iridoviridae'' is a family of viruses with double-stranded DNA genomes. Amphibians, fish, and invertebrates such as arthropods serve as natural hosts. There are currently 22 species in this family, divided among two subfamilies and seven genera. Nomenclature The name is derived from Iris, the Greek goddess of the rainbow. This name was chosen because of the "rainbow-like" iridescence observed in heavily infected insects and pelleted samples of invertebrate iridoviruses. Taxonomy The following subfamilies and genera are recognized (-''virinae'' denotes subfamily and -''virus'' denotes genus): * '' Alphairdovirinae'' ** '' Lymphocystivirus'' ** '' Megalocytivirus'' ** '' Ranavirus'' * '' Betairidovirinae'' ** '' Chloriridovirus'' ** '' Daphniairidovirus'' ** '' Decapodiridovirus'' ** '' Iridovirus'' Structure The virions are icosahedral with triangulation number (T) = 189–217, 120–350 nm in diameter and made up of three domains: an outer proteinaceous capsid, an int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asfarviridae
''Asfarviridae'' is a family of viruses, the best-studied of which is African swine fever virus, which are double-stranded DNA viruses. Taxonomy There is only one species under Asfarviridae in ICTV 2022: * Genus Asfivirus ** Species African swine fever virus African swine fever virus (ASFV) is a large, double-stranded DNA virus in the ''Asfarviridae'' family. It is the causative agent of African swine fever (ASF). The virus causes a haemorrhagic fever, hemorrhagic fever with high mortality rates i ... But, there may be more viruses: * Abalone asfarvirus * Dinodnavirus (Heterocapsa circularisquama DNA virus or hcDNAV) * Faustovirus * Kaumoebavirus * Pacmanvirus * Additional genomes known from environmental sampling of diverse marine, freshwater, and terrestrial habitats References {{Taxonbar, from=Q250204 Nucleocytoplasmic large DNA viruses Virus families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular microalgae, such as cyanobacteria, ''Chlorella'', and diatoms, to multicellular macroalgae such as kelp or brown algae which may grow up to in length. Most algae are aquatic organisms and lack many of the distinct cell and tissue types, such as stomata, xylem, and phloem that are found in embryophyte, land plants. The largest and most complex marine algae are called seaweeds. In contrast, the most complex freshwater forms are the Charophyta, a Division (taxonomy), division of green algae which includes, for example, ''Spirogyra'' and stoneworts. Algae that are carried passively by water are plankton, specifically phytoplankton. Algae constitute a Polyphyly, polyphyletic group because they do not include a common ancestor, and although Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invertebrate
Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate subphylum Vertebrata, i.e. vertebrates. Well-known Phylum, phyla of invertebrates include arthropods, molluscs, annelids, echinoderms, flatworms, cnidarians, and sponges. The majority of animal species are invertebrates; one estimate puts the figure at 97%. Many invertebrate taxon, taxa have a greater number and diversity of species than the entire subphylum of Vertebrata. Invertebrates vary widely in size, from 10 Micrometre, μm (0.0004 in) myxozoans to the 9–10 m (30–33 ft) colossal squid. Some so-called invertebrates, such as the Tunicata and Cephalochordata, are actually sister chordate subphyla to Vertebrata, being more closely related to vertebrates than to other invertebrates. This makes the "invertebrates" para ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protozoa
Protozoa (: protozoan or protozoon; alternative plural: protozoans) are a polyphyletic group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic debris. Historically, protozoans were regarded as "one-celled animals". When first introduced by Georg Goldfuss, in 1818, the taxon Protozoa was erected as a class within the Animalia, with the word 'protozoa' meaning "first animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae. This classification remained widespread in the 19th and early 20th century, and even became elevated to a variety of higher ranks, including phylum, subkingdom, kingdom, and then sometimes included within the paraphyletic Protoctista or Protista. By the 1970s, it became usual to require that all taxa be monophyletic (derived from a common ancestor that would also be regarded as protozo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
