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Composite Transposon
A composite transposon is similar in function to simple transposons and insertion sequence (IS) elements in that it has protein coding DNA segments flanked by inverted, repeated sequences that can be recognized by transposase enzymes. A composite transposon, however, is flanked by two separate IS elements which may or may not be exact replicas. Instead of each IS element moving separately, the entire length of DNA spanning from one IS element to the other is transposed as one complete unit. Composite transposons will also often carry one or more genes conferring antibiotic resistance. Flanked by SINEs in mammalian genomes Two SINEs may act in concert to flank and mobilize an intervening single copy DNA sequence. This was reported for a 710 bp DNA sequence upstream of the bovine beta globin gene. The DNA arrangement forms a composite transposon whose presence has been confirmed by the complete bovine genomic sequence where the mobilized sequence may be found on bovine chromosom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simple Transposon
A simple transposon also called "conservative transposon" is an insertion sequence (IS element) that contains its own coding 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 ... between the short, inverted, repeated sequences 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] |
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 transposon, transposable element. Insertion sequences have two major characteristics: they are small relative to other transposable elements (generally around 700 to 2500 base pair, bp in length) and only code for proteins implicated in the Transposable element, transposition activity (they are thus different from other transposons, which also carry accessory genes such as antimicrobial resistance, 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposon
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 C-value, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimicrobial Resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. Protozoa evolve antiprotozoal resistance, and bacteria evolve antibiotic resistance. Those bacteria that are considered extensively drug resistant (XDR) or totally drug-resistant (TDR) are sometimes called "superbugs".A.-P. Magiorakos, A. Srinivasan, R. B. Carey, Y. Carmeli, M. E. Falagas, C. G. Giske, S. Harbarth, J. F. Hinndler ''et al''Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria... Clinical Microbiology and Infection, Vol 8, Iss. 3 first published 27 July 2011 ia Wiley Online Library Retrieved 28 August 2020 Although antimicrobial resistance is a naturally-occurring process, it is often the result of improper usage of the drugs and management of the infections. Antibiotic resistance is a major subset o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bovine Genome
The genome of a female Hereford cow was published in 2009. It was sequenced by the Bovine Genome Sequencing and Analysis Consortium, a team of researchers led by the National Institutes of Health and the U.S. Department of Agriculture. It was part of an effort to improve livestock breeding and at the time was one of the largest genomes ever sequenced. Genome The size of the bovine genome is 3 Gb (3 billion base pairs). It contains approximately 22,000 genes of which 14,000 are common to all mammalian species. Bovines share 80 percent of their genes with humans; cows are less similar to humans than rodents (humans and rodents belong to the clade of Supraprimates) and dogs (humans and dogs belong to the clade of Boreoeutheria). They also have about 1,000 genes shared with dogs and rodents but not identified in humans. The charting of key DNA differences, also known as haplotypes, between several varieties of cattle could allow scientists to understand what is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tn10
Tn''10'' is a transposable element, which is a sequence of DNA that is capable of mediating its own movement from one position in the DNA of the host organism to another. There are a number of different transposition mechanisms in nature, but Tn''10'' uses the non-replicative cut-and-paste mechanism. The transposase protein recognizes the ends of the element and cuts it from the original locus. The protein-DNA complex then diffuses away from the donor site until random collisions brings it in contact with a new target site, where it is integrated. To accomplish this reaction the 50 kDa transposase protein must break four DNA strands to free the transposon from the donor site, and perform two strand exchange reactions to integrate the element at the target site. This leaves two strands unjoined at the target site, but the host DNA repair proteins take care of this. The target site selection is essentially random, but there is a preference for the sequence 5'-GCTNAGC-3'. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
