|
Simple Transposon
A simple transposon also called "conservative transposon" is an insertion sequence (IS element) that contains its own coding transposase between the short, inverted, repeated sequences Repeated sequences (also known as repetitive elements, repeating units or repeats) are short or long patterns of nucleic acids (DNA or RNA) that occur in multiple copies throughout the genome. In many organisms, a significant fraction of the genom ... that flank (present) its gene coding region. Transposase is responsible for excision and transfer while resolvase is responsible for resolution of the transfer. Simple transposition is also called cut-and-paste transposition because the element is cut out of its original site and pasted into a new one. References Mobile genetic elements {{genetics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposable Element
A transposable element (TE, transposon, or jumping gene) is a nucleic acid sequence in DNA that can change its position within a genome, sometimes creating or reversing mutations and altering the cell's genetic identity and genome size. Transposition often results in duplication of the same genetic material. Barbara McClintock's discovery of them earned her a Nobel Prize in 1983. Its importance in personalized medicine is becoming increasingly relevant, as well as gaining more attention in data analytics given the difficulty of analysis in very high dimensional spaces. Transposable elements make up a large fraction of the genome and are responsible for much of the mass of DNA in a eukaryotic cell. Although TEs are selfish genetic elements, many are important in genome function and evolution. Transposons are also very useful to researchers as a means to alter DNA inside a living organism. There are at least two classes of TEs: Class I TEs or retrotransposons generally f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insertion Sequence
Insertion element (also known as an IS, an insertion sequence element, or an IS element) is a short DNA sequence that acts as a simple transposable element. Insertion sequences have two major characteristics: they are small relative to other transposable elements (generally around 700 to 2500 bp in length) and only code for proteins implicated in the transposition activity (they are thus different from other transposons, which also carry accessory genes such as antibiotic resistance genes). These proteins are usually the transposase which catalyses the enzymatic reaction allowing the IS to move, and also one regulatory protein which either stimulates or inhibits the transposition activity. The coding region in an insertion sequence is usually flanked by inverted repeats. For example, the well-known IS''911'' (1250 bp) is flanked by two 36bp inverted repeat extremities and the coding region has two genes partially overlapping ''orfA'' and ''orfAB'', coding the transposase (OrfAB) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposase
A transposase is any of a class of enzymes capable of binding to the end of a transposon and catalysing its movement to another part of a genome, typically by a cut-and-paste mechanism or a replicative mechanism, in a process known as transposition. The word "transposase" was first coined by the individuals who cloned the enzyme required for transposition of the Tn3 transposon. The existence of transposons was postulated in the late 1940s by Barbara McClintock, who was studying the inheritance of maize, but the actual molecular basis for transposition was described by later groups. McClintock discovered that some segments of chromosomes changed their position, jumping between different loci or from one chromosome to another. The repositioning of these transposons (which coded for color) allowed other genes for pigment to be expressed. Transposition in maize causes changes in color; however, in other organisms, such as bacteria, it can cause antibiotic resistance. Transposition is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Repeated Sequence (DNA)
Repeated sequences (also known as repetitive elements, repeating units or repeats) are short or long patterns of nucleic acids (DNA or RNA) that occur in multiple copies throughout the genome. In many organisms, a significant fraction of the genomic DNA is repetitive, with over two-thirds of the sequence consisting of repetitive elements in humans. Some of these repeated sequences are necessary for maintaining important genome structures such as telomeres or centromeres. Repeated sequences are categorized into different classes depending on features such as structure, length, location, origin, and mode of multiplication. The disposition of repetitive elements throughout the genome can consist either in directly-adjacent arrays called tandem repeats or in repeats dispersed throughout the genome called interspersed repeats. Tandem repeats and interspersed repeats are further categorized into subclasses based on the length of the repeated sequence and/or the mode of multiplication ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
