Transitory expression of transposase

A clever approach developed by Hughes and Roth allows transposition of a defective transposon (MudJ) by transitory expression of Mu transposase from an adjacent transposon (Mud1). This trick relies on phage P22 to deliver the transposon to a recipient cell. Because of the headful packaging mechanism of phage P22, both MudJ and Mud1 cannot be packaged in the same phage head. However, it is possible to package MudJ and a portion of Mud1 including the transposase genes. When this linear DNA enters a recipient cell, the transposase is expressed, allowing transposition of the adjacent MudJ. The linear DNA fragment (including the transposase genes) is subsequently degraded, hence the MudJ insertions are unable to transpose again (i.e. the insertions are "stable").


Hughes, K., and J. Roth. 1988. Transitory cis complementation: a method for providing transposition functions to defective transposons. Genetics 119: 9-12.

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Last modified October 14, 2003