Nevertheless, the bulk of the binary tracts are just as random a mixture of two nucleotide bases as can be, and cannot be regarded as simple or even cryptic elements [ 46].
Several Integrative Mobile Elements exploiting Xer (IMEXs) were subsequently found in bacterial genomes (Das et al, 2011a), including phages (Huber and Waldor, 2002; Campos et al, 2003), cryptic elements related to phages or plasmids (Hassan et al, 2010) and genomic islands (Dillard and Seifert, 2001).
Nevertheless, it will be important to address the possible implication of Endo III in the integration strategies and life cycles of the other classes of IMEXs that are yet to be explored, such as Neisseriales genomic islands (Dillard and Seifert, 2001) and cryptic elements related to phages or plasmids (Hassan et al, 2010).
Interestingly, one of the primary sources of cryptic splicing elements are transposable elements [ 2].
We report five crystal structures and solution NMR data of GR DBD-κBRE complexes, which reveal that GR recognizes a cryptic response element between the binding footprints of NF-κB subunits within κBREs.
Multiple transgenic lines show such expression, indicating that it is indeed due to the duplicated B-block, not the effects of chromosomal flanking sequences on the transgene, i.e. the B-block includes a cryptic oscillator element whose ability to express is enhanced by the tandem duplication.
The GFP protein in the T line also has a 27 amino acid extension at the N-terminus because of the use of a cryptic promoter element upstream of the intended promoter in the transgene construct (Sasaki et al. 2015).
A prominent component involved in the genome shock is reactivation of cryptic transposable elements (TEs) in the hybrid genome, which is often associated with alteration in the elements' epigenetic modifications like cytosine DNA methylation.
High incidence of cryptic repeated elements in regions flanking microsatellites, which are associated with transposable elements, has been reported in examined genomes of deep-sea galatheid squat lobsters (Bailie, Fletcher & Prodöhl, 2010), hinting at recent elevated transposable element activity or mutation.
Cryptic regulatory elements within TEs can be epigenetically reactivated in cancer to influence oncogenesis in a process termed onco-exaptation4.
