FIGURE 1.

Nucleo-mitochondrial dual targeting of proteins is controlled by different mechanisms. (A) Alternative splicing of APL generates two transcripts that code for different proteins. (B) Alternative initiation of transcription and of translation controls the balance of mitochondrial and nuclear Lig1. (C) The Trxo1 pre-protein is imported into both mitochondria and the nucleus, although the control of partition between the two organelles is not yet understood. (D) The nuclear localization of PNM1 can be explained by re-localization of the mitochondrial mature protein into the nucleus.