What is HIMAR1?

HIMAR1 is an irritans subfamily member of the mariner family of class II, DNA-mediated, or short-inverted, terminal repeat-type transposable elements, and it is one of only two known active mariner elements. It was isolated from the horn fly, Haematobia irritans.

What are the two basic types of transposons?

Transposons themselves are of two types according to their mechanism, which can be either “copy and paste” (class I) or “cut and paste” (class II). Class I (Retrotransposons, aka retoposons): They copy themselves in two stages, first from DNA to RNA by transcription, then from RNA back to DNA by reverse transcription.

Do retrotransposons have inverted repeats?

Instead of LTRs, non-LTR retrotransposons have short repeats that can have an inverted order of bases next to each other aside from direct repeats found in LTR retrotransposons that is just one sequence of bases repeating itself.

What is a HIMAR1 mariner transposon?

The Himar1 mariner transposon is one of the two known active mariner elements that have been successfully utilized for a number of oral and non-oral bacteria such as Pseudomonas aeruginosa (Withers et al., 2014), Porphyromonas gingivalis (Klein et al., 2012), and oral streptococci (Nilsson et al., 2014).

Where did mariner transposon come from?

The Mariner transposon was first discovered by Jacobson and Hartl in Drosophila in 1986. A classification of the group was published in 1993, which divided such sequences in insects into the mauritiana, cecropia, mellifera, irritans, and capitata subfamilies, after the types of insects they are found in.

What are inverted repeat sequences?

An inverted repeat is a DNA sequence followed downstream by its reverse complement, potentially with a gap in the centre. Inverted repeats are found in both prokaryotic and eukaryotic genomes and they have been linked with countless possible functions.

What is the difference between transposons and retrotransposons?

What is the difference between Transposon and Retrotransposon? Transposons are cut from the origin and pasted at the target; conversely, retrotransposons being copied from the origin into RNA and transcribed at the target.

What do terminal inverted repeats do?

Inverted repeats have a number of important biological functions. They define the boundaries in transposons and indicate regions capable of self-complementary base pairing (regions within a single sequence which can base pair with each other).

What does inverted terminal repeats meaning?

Inverted terminal repeats that contain the origins of replication are present at the ends of the adenovirus genome. DNA synthesis is initiated at one of the two ends and proceeds to the other end.

What is Tn5 transposon?

Tn5 transposase is a bacterial enzyme that integrates a DNA fragment into genomic DNA, and is used as a tool for detecting nucleosome-free regions of genomic DNA in eukaryotes.

What is mariner transposon mutagenesis?

Mariner transposon mutagenesis systems have been developed for use in many Gram-negative and Gram-positive bacteria, including Clostridium difficile (8). The advantage of the mariner system is that its preferred target is a TA dinucleotide. This system was used to identify gene products required for C.

Where are inverted repeats found?

Are there hyperactive mutants of The Himar1 Mariner?

We used this fact to devise a genetic screen for hyperactive mutants of Himar1 transposase that enhance overall transposition from ≈4- to 50-fold as measured in an E. coli assay. Purified mutant transposases retain their hyperactivity, although to a lesser degree, in an in vitro transposition assay.

Which is the second element of The Himar1 sequence?

The second is the Himar1 element discovered by using homology-based PCR in the horn fly, Haematobia irritans, and reconstructed as a consensus sequence ( 7, 10 ). Both Mos1 and Himar1 require no host-specific factors for transposition and so have been advanced as generalized genetic tools ( 11 – 13 ).

How is a mini Himar1 transposase constructed by PCR?

A mini Himar1 transposon containing an ORF through the 3′ inverted terminal repeat (ITR) was constructed by PCR using a PCR-ligation-PCR method ( 25 ).

How is a Himar1 mutant detected in a cell?

Papillation Assay. A papillation assay to detect mutants of Himar1 was performed by transforming 1 μl of a ligation of mutated Himar1 coding sequences in pBAD24 into electrocompetent DL1 cells (see Fig. 2 A ). Screens of similar design have been used for bacterial transposons, including in Tn 5 and Tn 10 transposases ( 31 – 33 ).