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List Of RNAs
Ribonucleic acid (RNA) occurs in different forms within organisms and serves many different roles. Listed here are the types of RNA, grouped by role. Abbreviations for the different types of RNA are listed and explained. By role RNA abbreviations See also * List of cis-regulatory RNA elements * RNA: Types of RNA * Non-coding RNA A non-coding RNA (ncRNA) is a functional RNA molecule that is not Translation (genetics), translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally im ... References {{Reflist, 2 External linksRfam database— a collection of RNA familiesEuropean ribosomal RNA database RNA RNA RNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribonucleic Acid
Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydrates, nucleic acids constitute one of the four major macromolecules essential for all known forms of life. Like DNA, RNA is assembled as a chain of nucleotides, but unlike DNA, RNA is found in nature as a single strand folded onto itself, rather than a paired double strand. Cellular organisms use messenger RNA (''mRNA'') to convey genetic information (using the nitrogenous bases of guanine, uracil, adenine, and cytosine, denoted by the letters G, U, A, and C) that directs synthesis of specific proteins. Many viruses encode their genetic information using an RNA genome. Some RNA molecules play an active role within cells by catalyzing biological reactions, controlling gene expression, or sensing and communicating responses to cellular sign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kinetoplastida
Kinetoplastida (or Kinetoplastea, as a class) is a group of flagellated protists belonging to the phylum Euglenozoa, and characterised by the presence of an organelle with a large massed DNA called kinetoplast (hence the name). The organisms are commonly referred to as "kinetoplastids" or "kinetoplasts" The group includes a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments. Their distinguishing feature, the presence of a kinetoplast, is an unusual DNA-containing granule located within the single mitochondrion associated with the base of the cell's flagellum (the basal body). The kinetoplast contains many copies of the mitochondrial genome. The kinetoplastids were first defined by Bronislaw M. Honigberg in 1963 as the members of the flagellated protozoans. They are traditionally divided into the biflagellate Bodonidae and uniflagellate Trypanosomatidae; the former appears to be paraphyle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Long Noncoding RNA
Long non-coding RNAs (long ncRNAs, lncRNA) are a type of RNA, generally defined as transcripts more than 200 nucleotides that are not translated into protein. This arbitrary limit distinguishes long ncRNAs from small non-coding RNAs, such as microRNAs (miRNAs), small interfering RNAs (siRNAs), Piwi-interacting RNAs (piRNAs), small nucleolar RNAs (snoRNAs), and other short RNAs. Long intervening/intergenic noncoding RNAs (lincRNAs) are sequences of lncRNA which do not overlap protein-coding genes. Long non-coding RNAs include intergenic lincRNAs, intronic ncRNAs, and sense and antisense lncRNAs, each type showing different genomic positions in relation to genes and exons. Abundance In 2007 a study found only one-fifth of transcription across the human genome is associated with protein-coding genes, indicating at least four times more long non-coding than coding RNA sequences. Large-scale complementary DNA (cDNA) sequencing projects such as FANTOM reveal the complexity of this tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CRISPR
CRISPR () (an acronym for clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and destroy DNA from similar bacteriophages during subsequent infections. Hence these sequences play a key role in the antiviral (i.e. anti-phage) defense system of prokaryotes and provide a form of acquired immunity. CRISPR is found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea. Cas9 (or "CRISPR-associated protein 9") is an enzyme that uses CRISPR sequences as a guide to recognize and cleave specific strands of DNA that are complementary to the CRISPR sequence. Cas9 enzymes together with CRISPR sequences form the basis of a technology known as CRISPR-Cas9 that can be used to edit genes within organisms. This editing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-natural Antisense Transcript
Natural antisense transcripts (NATs) are a group of RNAs encoded within a cell that have transcript complementarity to other RNA transcripts. They have been identified in multiple eukaryotes, including humans, mice, yeast and ''Arabidopsis thaliana''. This class of RNAs includes both protein-coding and non-coding RNAs. Current evidence has suggested a variety of regulatory roles for NATs, such as RNA interference (RNAi), alternative splicing, genomic imprinting, and X-inactivation, X-chromosome inactivation. NATs are broadly grouped into two categories based on whether they act in cis or in trans. Trans-NATs are transcribed from a different location than their targets and usually have complementarity to multiple transcripts with some mismatches. MicroRNAs (miRNA) are an example of trans-NATs that can target multiple transcripts with a few mismatches. Cis-natural antisense transcripts (cis-NATs) on the other hand are transcribed from the same genomic Locus (genetics), locus as thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antisense RNA
Antisense RNA (asRNA), also referred to as antisense transcript, natural antisense transcript (NAT) or antisense oligonucleotide, is a single stranded RNA that is complementary to a protein coding messenger RNA (mRNA) with which it hybridizes, and thereby blocks its translation into protein. asRNAs (which occur naturally) have been found in both prokaryotes and eukaryotes, and can be classified into short (200 nucleotides) non-coding RNAs (ncRNAs). The primary function of asRNA is regulating gene expression. asRNAs may also be produced synthetically and have found wide spread use as research tools for gene knockdown. They may also have therapeutic applications. Discovery and history in drug development Some of the earliest asRNAs were discovered while investigating functional proteins. An example was micF asRNA. While characterizing the outer membrane porin in ''E.coli'', some of the promoter clones observed were capable of repressing the expression of other membrane porin s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SL1 RNA
This family represents the SL1 RNA. The gene encoding SL1 RNA is commonly, but not always, located in the spacer region between 5S-rRNA genes. The SL1 RNA is involved in trans-splicing, which is a form of RNA processing. The acquisition of a spliced leader from an SL RNA is an inter-molecular reaction that precisely joins exons derived from separately transcribed RNAs. This mechanism of mRNA maturation has been shown to occur in a number of lower eukaryotes and is commonplace in nematodes. References External links * Non-coding RNA {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telomere
A telomere (; ) is a region of repetitive nucleotide sequences associated with specialized proteins at the ends of linear chromosomes. Although there are different architectures, telomeres, in a broad sense, are a widespread genetic feature most commonly found in eukaryotes. In most, if not all species possessing them, they protect the terminal regions of chromosomal DNA from progressive degradation and ensure the integrity of linear chromosomes by preventing DNA repair systems from mistaking the very ends of the DNA strand for a double-strand break. Discovery In the early 1970s, Soviet theorist Alexei Olovnikov first recognized that chromosomes could not completely replicate their ends; this is known as the "end replication problem". Building on this, and accommodating Leonard Hayflick's idea of limited somatic cell division, Olovnikov suggested that DNA sequences are lost every time a cell replicates until the loss reaches a critical level, at which point cell division end ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Telomerase RNA
Telomerase RNA component, also known as TR, TER or TERC, is an ncRNA found in eukaryotes that is a component of telomerase, the enzyme used to extend telomeres. TERC serves as a template for telomere replication (reverse transcription) by telomerase. Telomerase RNAs differ greatly in sequence and structure between vertebrates, ciliates and yeasts, but they share a 5' pseudoknot structure close to the template sequence. The vertebrate telomerase RNAs have a 3' H/ACA snoRNA-like domain. Structure TERC is a Long non-coding RNA (lncRNA) ranging in length from ~150nt in ciliates to 400-600nt in vertebrates, and 1,300nt in yeast (Alnafakh). Mature human TERC (hTR) is 451nt in length. TERC has extensive secondary structural features over 4 principal conserved domains. The core domain, the largest domain at the 5’ end of TERC, contains the CUAAC Telomere template sequence. Its secondary structure consists of a large loop containing the template sequence, a P1 loop-closing helix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y RNA
Y RNAs are small non-coding RNAs. They are components of the Ro60 ribonucleoprotein particle which is a target of autoimmune antibodies in patients with systemic lupus erythematosus. They are also reported to be necessary for DNA replication through interactions with chromatin and initiation proteins. However, mouse embryonic stem cells lacking Y RNAs are viable and have normal cell cycles. Structure These small RNAs are predicted to fold into a conserved stem formed by the RNA's 3′ and 5′ ends and characterized by a single bulged cytosine, which are the known requirements for Ro binding. Function Two functions have been described for Y RNAs in the literature: As a repressor of Ro60, and as an initiation factor for DNA replication. Mutant human Y RNAs lacking the conserved binding site for Ro60 protein still support DNA replication, indicating that binding to Ro protein and promoting DNA replication are two separable functions of Y RNAs. Although Y RNA-derived small RN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all living organisms acting as the most essential part for biological inheritance. This is essential for cell division during growth and repair of damaged tissues, while it also ensures that each of the new cells receives its own copy of the DNA. The cell possesses the distinctive property of division, which makes replication of DNA essential. DNA is made up of a double helix of two complementary strands. The double helix describes the appearance of a double-stranded DNA which is thus composed of two linear strands that run opposite to each other and twist together to form. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as semiconservative replication. As a result of semi-conservative rep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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