Control of transposition activity

Transposition activity is generally maintained at a low level. An often cited reason for this is that high activities and the accompanying mutagenic effect of genome rearrangements would be detrimental to the host cell (see (Doolittle, et al., 1984)). Endogenous transposase promoters, in contrast to those assembled by juxtaposition of -10 and -35 hexamers in those IS families whose transposition passes through a double-strand circular transposon intermediate, are generally weak and many are partially located in the terminal IRs. This would enable their autoregulation by Tpase binding.

References :

• Doolittle WF, Kirkwood TB & Dempster MA (1984) Selfish DNAs with self-restraint [news].Nature 307: 501-502.