These various (non-mutually exclusive) types of copies may provide information on how MLEs decay over time; i.e., through loss of transposition ability or loss of activity.
The piggyBac transposon system has recently attracted a great deal of attention because the system is a nonviral gene-delivery approach that uses DNA-transposition ability for the stable expression of exogenous genes via a 'cut-and-paste' mechanism.
Hence the size homogeneity is not the result of selection for transposition ability and the observed necessity for a certain size range is difficult to understand here.
The abundance of deleted copies is likely the consequence of the huge number of copies of this mariner lineage, but, except for few sequences, we have no trace of amplification by transposition of these shortened copies, and this cluster do not represent a bona fide MITE lineage, that would suggest that most of internal deletions are harmful for transposition ability.
A side effect of the rearrangement process is the large increase in the size of the inverted repetition, which may increase transposition ability by stabilizing the synaptic complex.
This may be regarded as an ineluctable fate of TEs, which are thought not to be subjected to intense purifying selection for their transposition ability.
This finding suggests that this copy may also have transposition ability.
Passive transposition of a whole palette of sequences is possible due to the ability of mechanisms involved in transposition to recognize DNA secondary structures, such as inverted repeats (Craig 1995; Izsvák et al. 1999; Coates et al. 2011).
Because of the redundancy of the encoded functions, disruption by transposition seemed to have no effect on the ability of the strains concerned to degrade inositol.
These works have shown the ability of Tc1-like transposases to catalyze transposition in a variety of cells and species.
